Performance of Exterior Paints on Houses: Second Progress Report

Publisher’s version / Version de l'éditeur:

Vous avez des questions? Nous pouvons vous aider. Pour communiquer directement avec un auteur, consultez la

première page de la revue dans laquelle son article a été publié afin de trouver ses coordonnées. Si vous n’arrivez pas à les repérer, communiquez avec nous à PublicationsArchive-ArchivesPublications@nrc-cnrc.gc.ca.

Questions? Contact the NRC Publications Archive team at

PublicationsArchive-ArchivesPublications@nrc-cnrc.gc.ca. If you wish to email the authors directly, please see the first page of the publication for their contact information.

https://publications-cnrc.canada.ca/fra/droits

L’accès à ce site Web et l’utilisation de son contenu sont assujettis aux conditions présentées dans le site LISEZ CES CONDITIONS ATTENTIVEMENT AVANT D’UTILISER CE SITE WEB.

Report (National Research Council of Canada. Division of Building Research), 1953-02-01

READ THESE TERMS AND CONDITIONS CAREFULLY BEFORE USING THIS WEBSITE.

https://nrc-publications.canada.ca/eng/copyright

NRC Publications Archive Record / Notice des Archives des publications du CNRC :

https://nrc-publications.canada.ca/eng/view/object/?id=680e87c7-682d-40a5-831b-78a48dcfe50a https://publications-cnrc.canada.ca/fra/voir/objet/?id=680e87c7-682d-40a5-831b-78a48dcfe50a

NRC Publications Archive

Archives des publications du CNRC

For the publisher’s version, please access the DOI link below./ Pour consulter la version de l’éditeur, utilisez le lien DOI ci-dessous.

https://doi.org/10.4224/20386722

Access and use of this website and the material on it are subject to the Terms and Conditions set forth at

Performance of Exterior Paints on Houses: Second Progress Report

...--_

....

_._._....

- - - -

---NATIONAL RESEAROH COUNCIL CANADA

PERFORj,U\NCE OF EXTERIOR PAINTS

on

HOUSES Second Progress Report

by

C.Y. Hopkins, Division of Chemistry and

E.V. Gibbons, Division of BUilding Research

i

ｾｎａｬ YZEO

(NOT FOR PUBLICATION)

Pe bruar-y ,

1953

Research Report No.8 of the

Division of Building Research ottawa

PREFACE

This is the second Progress Report on

the study of exterior paint deterioration which was begun by the Division of Building Research

at the request of Central Mortgage and Housing

Corporation. The first Progress Report was issued

as D.B.R. Report R-l, dated October 1948.

When these studies started, research work into the properties of paints was being conducted in the Division of Chemistry under Dr. C.Y. Hopkins. Dr. Hopkins kindly co-operated in the work and the present report contains much information prepared

and written by him. The Division of Building

Research is grateful for this assistance.

On September 1, 1952, the responsibility for

paint research in the Council was transferred from the Division of Applied Chemistry to the Division of Building Research, and is now being carried out in the Building Materials Section of the Division, under Mr. Gibbons, the other author of this report.

The problem herein discussed is a complex one, and requires much more study before even

tentative answers to all the questions which it

raises can be formUlated. This is therefore a

report of progress only. The Division of BUllding

Research plans to extend its studies with the erection of a special experimental structure at

Ottawa during the summer of 1953.

R.F. Legget, Director.

INTRODUCTION

When. paint on the exterior of homes fails by

blistering and ｰ･･ｬｩｮｧｾ a serious maintenance problem

resultso Such failure has occurred across Canada with some

localities being worse than otherso

In ＱＹＴＸｾ at the request of the Central Mortgage

and Housing Corporation9 an investigation was begun by the

Divisions of Chemistry and Building Research of the National

Research Councilo At that time an extensive investigation

was carried out in Vancouver and Victoria by the authors of

this Report o The results of this study appeared in Research

Report Noo I of the Division of Building Research o This

Report outlined recommendations to assist in overcoming the early failure of exterior paints and also included suggestions with reference to changes in structural details, preparations

of the wood for repainting and the paint and its applicatione Of necessitY9 a study of paint performance must be continued for a number of years to investigate adequately all

the factors involvedo Since ＱＹＴＸｾ the location of the first

study has been re=visited to observe the effect of

preventa-tive measures and the performance of repainted homese Study

of the problems of exterior paint failure has been carried

out in other Canadian ｣･ｮｴｲ･ｳｾ on private homes and on houses

in housing projects operated by Central Mortgage and Housing

Cor-po nat Lon ,

This Report is a second progress report of

observa-tions made during the past 3 yearso For the most ｰ｡ｲｴｾ it

contains results of investigations carried out in the Vancouver

｡ｲ･｡ｾ and experimental repainting in Wrightville 9 PoQo and visits to Corporation housing projects in a number of munici-palitieso

A bibliography of references on subjects relevant to

the material is included with this Report"

The authors wish to acknowledge with thanks the kind co=operation received from officials of the Central Mortgage and Housing Corporation in all phases of these investigationse

SUMMARY

One of the chief causes for the premature failure of exterior paints on houses in the Vancouver area was thought to have been due to excessive amounts of water under the

siding some time after paintingo A number of recommendations

to help overcome the accumulation of this moisture were outlined in Division of Building Research Report R 1 dated

October, 19480 The Central Mortgage and Housing Corporation,

in so far as was possible without undertaking major structural

｣ｨ｡ｮｧ･ｳｾ incorporated these recommendations in their repain-ting programo

After removing all old paint from houses in this

survey with a strong alkalip the houses were washed thoroughly

wi th water and allowed to stand for several weekso No painting

was done if the moisture content of the wood exceeded 14 per

cent ,

The recommendations were carried out on these houses

in 1949 and 1950 and were examined for performance in 19510

Fbr the most partp all the houses that had been repainted

according to suggestions were found to be in favourable

c ond Ltton,

Several significant observations have been made

resulting from investigations during the past 3 year-s , Which,

it is ｨｯｰ･､ｾ will aid in the prevention of exterior paint

PROGRESS REPORT ON EXAMINATION OF

EXTERIOR PAINT ON HOUSES IN THE VANCOUVER AREA

Following the

1948

investigation in the Vancouver

area of the failure of exterior paints on housesD the

following changes for these basementless houses were ｭ｡､･ｾ

10 The installation of ventilators in the crawl

spaces preferably located at the ｣ｯｲｮ･ｲｳｾ

20 the installation of attic vents in the gable

ends with a total area of the openings not less than two square feet per house;

30

diversion of water from down=spouts away from

the house and levelling earth in crawl space

area to assist the drainage of ground ｷ｡ｴ･ｲｾ

40

re-nailing pieces of siding which did not

make tight joints and moving earth awa.y from the lower portions of the wood skirting with which it was in contact to prevent water from entering the sidingo

For ｰ｡ｩｮｴｩｮｧｾ in addition to recommending thRt an

approved paint be ｵｳ･､ｾ it was recommended that (a) all loose

and scaling paint be removedD preferably by use of a blow

torch9 (b) the siding be checked for ｾｯｩｳｴｵｲ･ content and be

dry before repainting was ｢･ｧｵｮｾ ｬｯ･ｯｾ below

14

per centj (c)

the first coat be applied by brush to bare wood$) each coat in the order of two mils in thickness in order to avoid unduly thick coatsD

Cd)

records of the paint usedg weather ｣ｯｮ､ｩｴｩｯｮｳｾ

da.te of ｰ｡ｩｮｴｩｮｧｾ and samples of the paint used and the name

of the manufacturer be kept for future referenceo

ｒ･ｅ｡ｬｮｴｩｾｧ ,Procedure

In

1949

9 houses in the municipality of North Vrolcouver

examined in

1948

by the authors were prepared for repaintingo

The houses in this project were located in a low=lying area

and for the most partp good drainage of the ground Was not

possibleo At first the exterior paintp which appeared to be

fixed firmly and in good conditlon9 was not removedo It was

found9 however9 very shortly after repaintingD that blistering

appeared in many instances where the old paint had been

allowed to remalno It was then decided to remove all old

paint" Sub se quent.Ly , a number of houses were r-ep a Irrte d , 'I'he se

houses were examined after a period of a few months by officials

of the Corporation and an improved perfer mance of the paint was notedo

= 2 ＼ｾ

During the repainting operations» it was reported that it was difricult to get all of the wood siding on the

houses below a moisture content of 14 per cento Because of

ｴｨｩｳｾ it was ne ce s s ar-y to select houses which were dry and leave those with wet walls to remain for longer drying

periodso The siding on the east and north walls was usually

wettest and , in addition,9 these walls were much slower in

drying out than the south and west exposureso It is of

interest to note that in the survey of exterior wall conditions

in

1948

that,9 on the whole9 the condition of the paint on the

east and north walls was worse than on the other two wallso The Corporation reported that,9 with the exception of the first few housesg an alkali paint remover was used for

cleaning all of the old paint from the sidingo The strong

alkaliD while requiring extreme precaution on the part of

personnel to avoid burnsD was found to be very effectiveo

After the removal of the old paint the houses were washed thoroughly with water and allowed to stand for several weekso

Fortunately the weather was fine during this period. No

painting was done when it was raining or if it had rained within at least twenty=four hours or if the moisture content

of the wood exceeded

14

per cento Information supplied

indicated that good weather prevailed for some time after the painting of this pro jec t ha.d been compLe bed ,

The paint used on these houses complied with the Canadian Government Specifications Board specification with the exception of a few houses for which old stock paints were

usedo The surface preparation and painting were done by

painters on the maintenance staff of the Corporationo

At the time the preceding information was obtained, the application of paint referred to had been in service for

twelve months0 It was not possible to do much with the overall

drainage of the ｰｲｯｪ･｣ｴｾ it could only be improved somewhat

with the individual ｨｯｵｳ･ｳｾ ｩｯ･ｯｾ by grading around the skirting

and removing earth pushed against the lower boards. In one

instance of early ｦ｡ｩｬｵｲ･ｾ it was noted that the earth had

been pushed back again but no evidence of blistering or peeling

had at that time appeared on any houses from which all old

paint had been completely removed. The houses on which only

part of the old paint had been removed had some blisters and failure but this was of a minor nature compared with the . extensive blistering previously encountered after repaintingo

The houses in these projects were examined by

Dro Co Yo Hopkins during ｆ･｢ｲｵ｡ｲｹｾ ＱＹＵＱｾ and their condition

was found to be as ｦｯｬｬｯｷｳｾ

General Appearance ｯｾｈｯｵｳ･ｳｯ］ｔｨ･ houses that had been repainted

by this procedure in

1949

and in

1950

were generally in good

condition. Some had been painted as early as June,

1949

{20

3

-Churchill Streets and Roosevelt Streeto There was still a

considerable num.ber of houses that had not been repainted and many of these were in poor condition with some peeling

of paint. It was stated that the location is unfavourable

since it lacks good drainageo Some of the houses are being

moved for this reasono

Moisture Conditions.=The day of inspection was cloudy but dry

and the previous day had been bright and sunny. The ground

was damp and there was water lying on the surface in placeso Moisture tests were made on the exterior siding of several

houses and a wide variation was noted o The moisture content

on some houses was between 12 and 16 per ｣･ｮｴｾ a reasonably

good condition. On ｯｴｨ･ｲｳｾ the moisture rose to 20 per cent

in one or two places and in one house (931 Marine Drive) the moisture content was 30 per cent on the west side at a point

5 feet above ground level. There was no apparent reason for

this wall to be so wet in comparison with other houses. The

siding showed numerous stains owing to water running out from

between the joints. This condition was not unexpected

considering the extremely damp ground and heavy rainfall. When there has been considerable generation of water vapour within the house the sum of all these factors may lead to

saturation of the wall space and exterior siding.

It was stated that some of the houses had been painted with a reconditioned paint which was thinned down

considerably before useo This would have the effect of

producing a rather thin coat with probably low gloss and relatively little resistance to the passage of moistureo While such a coating would not be likely to blister or peel, neither would it have the ability to prevent moisture from

rain and damp air penetrating the sidingo ａ｣｣ｯｲ､ｩｮｧｬｹｾ with

this type of coating, the siding and wall space may become

fairly damp during the rainy seasono This probably does no

harm unless it is severe enough to cause rotting of the woodo It has the advantage of avoiding blistering and peeling.

Comparison with Appearance in 1948.-No. 803 Churchill Street

showed bad peeling on the east and west sides in 1948. It

was repainted in June 1950 and appeared to be in good condition

at the time of the 1951 examinationo The moisture content was

less than 16 per cent over most of the area o Photographs of

two houses taken during 1948 and again in 1951 have been included in AppendiX Bo

No. 823 Churchill Street showed bad peeling on the

north and east sides when examined in 19480 It was stripped

and repainted in June 1950 and was in good condition at the time of the 1951 examination (Figs o 1 and 2).

Noo 833 Churchill Street showed bad peeling on the

east and north sides in 19480 It was in good condition at the

=

4

-NOe 843 Churchill ｓｴｲ･･ｴｾ repainted in June ＱＹＵＰｾ

was also in good conditiono

Noo 802 Roosevelt Street showed bad blistering and

peeling in

19480

It was in good condition at this ｩｮｳｰ･｣ｴｩｯｮｾ

Mildewo=As mentioned in the 1948 reportp some of the damage to

paint may have been caused by ｭｩｬ､･ｷｾ Figure 5 shows severe

mildew on one of these houseso It would probably be desirable

to add a mildew=proofing agent to all paints used in this projecto

Discussion and Recommendations

The procedure of repainting as carried out in 1949

and in 1950 has given good results to dateo It is evidently

necessary to remove all of the old paint before repaintingo This conclusion was confirmed by work on similar houses at Wrightville» PaQo which is described in detail later in this Reporto

Removal of the old paint may be accomplished by the

use of a blow torch or by liquid paint removero If a liquid

is usedi it is essential that any residue be completely removed

by thorough rinsingo

The precautions taken by the Corporation and those listed in the 1948 Report (po21=22) are considered essentialo Use of the moisture tester at frequent intervals would make it possible to identify the houses with the highest moisture

concentration9 such as the one referred to previously (30 per

cent moisture) 0 These houses could then be improved by

installing additional vents9 a moisture barrier below the

floor or other suitable meanso

Houses in which the sidewalls cannot be kept dry may best be painted with a specially formulated paint which gives

a semi=permeable coat and ｾｩ｣ｨ is resistant to blisteringo

Houses maintained in reasonably dry condition may be painted with the regular Canadian Government specification paint from approved supplierso

Consideration should be given to the use of a ｭｩｬ､･ｷｾ

proofing agent to paint for this localityo

The preceding information refersp for the most partp

to rental units built either during or shortly after the war

by Wartime Housing Limitedo The performance of the exterior

paint on a number of other housing projects of the Corporation and privately owned dwellings more recently constructed has

been followed during the past three years. Failure has not

been confined to the low=cost type of home0 It has also

=

5

=

where extra precautions had been taken to construct and

properly ｾ｡ｩｮｴ｡ｬｮ them. The houses referred to here were

built with full basements and ground moisture was not judged

to be a contributing factor. A number of significant

observations have been made:

Overhang of, Roof at Gable End and ｅ｡ｶ･ｳＮｾｉｴ has been observed

that the paint on houses with a wider projection of the

ｯｶ･ｲｨｾｾｧ of the roof at gable end and at the eaves showed

an improved performance. This has been particularly true

of the one=storey type of bungalow with a wide overhang. If

dwellings of this type have been provided with adequate

ventilation for the attic space and in the soffit a noticeable improvement has been observed on them compared with the paint on adjacent homes with little protection of the roof overhang. This has also been true of the paint on one-and-one-half

storey dwellings; the paint on the sidewalls with wide overhangs being in better condition than the paint on the ends and in the gables where little protection from the

elements was provided. As mentioned previously, failure of

the paint has been attributed to moisture accumulating in the siding beneath the film of paint from a number of sources.

The wider ｯｶ･ｲｨ｡ｮｧｳｾ in addition to providing protection from

the ･ｬ･ｭ･ｮｴｳｾ assisted in preventing rain gaining access through open joints of the wall surfaces.

Siding ｆｩｸ･ｾ Place Horizontally and Vertically.=A number of

houses ･ｸ｡ｾｩｮ･､

hoo

the siding on the gable ends placed

verticallyo It was noted that where the vertical siding

butted a belt course placed horizontally at the top of the first floor levelp failure of the paint in this area was

quite general. Although metal flashing was ｰｲｯｶｩ､･､ｾ in

some cases insufficient pitch was provided to permit rain water to run off quickly enough from the unsealed ends of the

siding. Since water travels more rapidly with the ｧｲ｡ｩｮｾ it

was considered that this type of design may provide areas of weakness unless added precautions are taken.

Wall Openingso=Paint failures have been noted to be most

frequent around window openings. This has been particularly

so of metal windows located in the gable ends of houses.

This observation applied whether the siding was fixed

vertical-ly or horizontalvertical-ly. This may have been caused either by

inadequate flashing and the entrance of rainwater from the exterior or by moisture vapour entering the wall adjacent to the window during cold weather periods and subsequently

affecting the paint film.

Additional locations on the wall which showed frequent paint failure include the junctions between the

siding and the corner ｢ｯ｡ｲ､ｳｾ door ｣｡ｳｩｮｧｳｾ masonry chimneys,

- 6 =

Quality of the Wood.=It has been reported by other observers

that paints adhere better and last longer on ･､ｧ･ｾｧｲ｡ｩｮ･､ than

on flat=grained boards. Their explanation for this has been

attributed to the difference in density between summer wood

and spring wood. As the latter is lighter because of larger

cavities in the wood cells it permits greater mechanical grip

of the paint. ｆｬ｡ｴｾｧｲ｡ｩｮ･､ boards exposed larger areas of

summer wood than edge=grained boards and were consequently

sUbject to earlier failure. ｃｯｲｲ･ｳｰｯｮ､ｩｮｧｬｹｾ when the heart

ｳｩ､ｾｯｦ flat=grained boards were exposed for ｰ｡ｩｮｴｩｮｧｾ there was a geater tendency for the paint to lift at the edges of the bands of summer wood which loosen and curl outward with

changes in moisture content. Boards with a large number of

ｫｮｯｴｳｾ splitsp and loose splints were found unsuitable.

Observations by the authors of this Report have indicated that there are numerous instances where failure of

the paint has been due to the grade of lumber used. One

house in particular was examined in detail while it was being

painted. The moisture content of the wood varied from 8 to

10 per cent. Two years later, the only failure of the paint

was located over areas of poor quality lumber. Its appearance

had been marred by permitting the use of a few boards either

with large knotsp ｳｰｬｩｮｴ･ｲｳｾ or ｦｬ｡ｴｾｧｲ｡ｩｮ･､ surfaces at the

time of ｣ｯｮｳｴｲｵ｣ｾｩｯｮｯ The extra costs which are necessary

to prepare inferior grades of lumber for ｰ｡ｩｮｴｩｮｧｾ such as

shellacking knotsp puttying ｣｡ｶｩｴｩ･ｳｾ removing pitch ｰｯ｣ｫ･ｴｳｾ

and other common defectsp may well offset any economical

advantages of its use as siding in the first instance o Painting.=One diffiCUlty which was first encountered in

ascertaining causes for paint failure was the lack of records of the paint and painting of a number of privately owned

homes and housing projects. This has now been overcome in

so far as Central Mortgage and Housing Corporation is

concerned through their use of paint data formso (Sample

copies of these forms are included in Appendix A of this

Reporto) A form is completed by the inspectors for at least

five houses of each project during painting operations. The

forms are self=explanatory and when completed include data pertaining to (I) wall construction (2) painting history with

reference to the number of ｣ｯ｡ｴｳｾ branch and manufacturer,

how ｡ｰｰｬｩ･､ｾ and date of ｡ｰｰｬｩ｣｡ｴｩｯｮｾ as well as a record of the weather before and after the actual painting.

The information forwarded on completion of these forms has been of great assistance when examining the paint

on projects of recent constructione Their continued use is

recommended and no doubt will be a contributing factor in assisting in overcoming paint failure problems.

The change in moisture content of the wood siding on one housing project in Ottawa (built by the Corporation)

7

-houses were either one or ｯｮ･Ｍ｡ｮ､Ｍｯｮ･ｾｨ｡ｬｦ storey type with

full basementso Vapour barrier paper had been installed on

the inside face of the studding on all exterior walls during their constructiono

The moisture content of the siding was determined by means of an electrical resistance moisture meter on each exposure of eight houses at intervals of apprOXimately six

weekso The low and high readings during this eighteen-month

period were found to be as follows:

EXPOSURE - NOISTURE CONTENT

House No0 N W S E 11 8 ｾ 12 8 = 11 7 = 11 8 = 11 86 9 = 12 8 = 10 7 = 10 8 = 12 98 8 = 12 7 = 12 7 = 10 9 = 12 111 7 - 9 7 - 8 7 = 11 9 - 11 121 8 = 12 7 - 10 7 = 11 7 = 11 127 8 = 12 7 ₌ 11 7 ｾＬ 12 8 - 11 133 9 <, zi» 7 = 8 7 = 12 7 c, 10 148 9 = 13 7 - 11 8 = 11 8 = 13

*One particular board on this exposure had this high moisture content the first time readings were takeno It has decreased gradually until at the latest reading

ｴ｡ｫ･ｮｾ the moisture content was found to be 14 per cento

Adjacent boards were considerably lower == 8 to 11 per cento

These houses were the first group with vapour

barrier paper installed during their construction which have

been followed in detailo As ｹ･ｴｾ approximately two years

after they were painted and o ccupd e d , no paint failure of

any kind has been observed o Close supervision of the

painting operations was maintained on these houseso Good

inspection of the painting operations may well account for the improved performance of paint on a group of thirty houses of similar design but without vapour barriers where only a few isolated instances of peeling over small areas have

o ccur-r-ed ,

A number of conditions which affect the performance

of exterior paints have been st at.e d , The quality of the

paint and the Ｑｵｭ｢･ｲｾ the design of the structure with

reference to overhang wood ｳｩ､ｩｮｧｾ wall ｯｰ･ｮｩｮｧｳｾ workmanship

in construction and painting are all closely related to the

ultimate performance of the protective coatingo The usefulness

in maintaining good job records cannot be over-emphasizedo Special precautions are necessary for repainting houses on

which premature failure has occurredo This paint has been

described in detail and follows in the next portion of this Report on experimental studies conducted on a number of houses

8

-EXPERIMENTAL PAINTING OF HOUSES IN WRIGHTVILLE, Po ｾＮ

= 9

-SUMMARY

A study of twelve houses in a large CoM.H.C. housing

project in ｗｲｩｧｨｴｶｩｬｬ･ｾ PoQo was conducted over a period of

two years to evaluate the factors influencing the adherence of paint on wood sidingo

The original paint illl these houses had peeled to

a considerable extent. Eight of them were prepared for

repainting by ｷｩｲ･ｾ｢ｲｵｳｨｩｮｧ and four by stripping completely

with blow=torcho They were re-painted under controlled

conditions and inspected at intervals for two years thereafter, with particular attention to moisture levels in the woodo

Serious peeling recurred within two years on seven of the

twelve houseso Analysis of the data shows that recurrence

resulted from (a) re=painting over the old insecure paint coating and (b) accumulation of excessive moisture in the wood sidingo

All of the houses prepared by ｷｩｲ･ｾ｢ｲｵｳｨｩｮｧ except

onep developed serious peeling within two years. None of the

houses that were stripped by blow-torch developed serious peeling in two yearso

Excessive moisture accumulation (over 20 per cent) was observed in the wood siding of eight of the houses,

several months after painting. Five of these showed severe

peeling in the second year and the remaining three showed slight peeling.

The two houses which had been stripped before repainting and which maintained a low moisture content did not develop peeling in two yearso

Old Paint Moisture in Wood Noo of Houses Result

Stripped Normal 2 No peeling

Stripped High 2 Slight peeling

Not stripped Normal 2 Severe peeling

Not stripped High (1 Slight peeling

10

-EXPERIMENTAL PAINTING OF HOUSES IN WRIGHTVILLE, P.Q.

Construction of houses in large groups has apparently led to difficulties in adhesion of paint to wood siding.

Serious cases of paint peeling have occurred in various

widely-separated localities. The reasons are not immediately apparent.

It is likely that a combination of unfavourable factors is responsible.

Assistance in studying this problem was requested

by Central Mortgage and Housing Corporation in

1947

and

1948.

A report on one group of houses was made on December 2,

1947.

During

1948

it was agreed to undertake repainting of a small

group of existing houses, the work to be supervised closely, in order to determine whether good paint durability could be achieved when the painting procedure and other variables were

controlled. A painting contractor was chosen by C.M.HoC. and

the job was started on October 1st,

1948.

Gene ral Plan

Twelve existing houses in Wrightville, P.Q., were

selected for the experimental painting. They were built and

painted in 1946 and the exterior paint had peeled to a considerable extent.

It was proposed to s trip the old paint completely from four houses by blow-torch and scraper and to repaint

them using three coats of paint. The remaining eight houses

were to be merely ｷｩｲ･ｾ｢ｲｵｳｨ･､ to remove any loose or scaling

paint and to be repainted using two coats of paint.

The paints were to be taken mainly from stocks owned by C.M.H.C. but two lots of paint were to be purchased specially for comparison.

It was planned to have the paint applied by spray, except the first coat on bare wood, which would be applied by

brush. The trim paint was also brushed.

An

additional part of the plan stipUlated the

application of aluminum paint to the interior walls of two houses as a vapour barrier.

The experiments were therefore intended to give the following comparisons:

11

-(a) Complete stripping of old paint versus wire-b::-ushing.

(b) Paints from C.M.H.C. stocks versus specially-chosen paints.

(c) Aluminum paint on interior walls as a vapour barrier versus no special treatment of interior walls.

Inspection

Inspections were made by National Research Council personnel once a day during the painting operations, which

covered a period of three weeks. It was not possible to

place a ｦｵｬｬｾｴｩｭ･ inspector on the job. As a reSUlt, there

was some deviation from instructions and the records are not as complete as desired.

After completion of the work, inspections were made at convenient intervals to observe the moisture content of the wood siding and the condition of the paint.

List of houses and their condition

The location of the houses and their original colours are shown in Tabl e I.

Table I

Houses Selected for Experimental Painting

Number 1 2 3

4

5

6

7

8 9 10 11 12 Original Colour cream cream cream cream grey cream cream grey white white

Condition of old paint

as at September

1948

severe peel ing severe peeling severe pee ling severe peeling not recorded moderate peeling severe peeling moderate peeling severe peeling severe peeling severe peeling moderate peeling Rating poor poor poor bad poor bad poor poor bad poor poor The area is level, fairly well drained, and has no

large trees. It is a residential district and there are no

12

-The houses are of wood construction, without basement,

and have wood siding and asphalt-shingled roofs. All but one

are ｯｮ･Ｍ｡ｮ､ｾｯｮ･Ｍｨ｡ｬｦ storey and were built without attic vents. Number 10 is a single-storey house and had attic vents installed at the time of construction.

The dwellings chosen for experimental painting are

part of a group of about two hundred. Many of ｴｨ･ｳ･ｾ however,

have the walls finished with wood shingles or asbestos-cement shingles and do not offer the same painting problems.

The houses are on a concrete block foundation without

basement. There are four openings in the foundation for

ventila-ting the crawl space but these are rather small. Some of the

tenants had sealed up tne openings in order to conserve heat. The walls and upper ceiling contain mineral fibre

insulation. It is understood that there is no vapour barrier

but records of construction are incomplete.

The original paint had peeled over large areas on

most of these houses. Records of the time of painting or type

of paint used are not available. Analysis of the old paint

coatings from two houses indicates that the paints were not of first grade quality but were of a grade that would be expected to give two years' service without peeling, under favourable

conditions. It was reported that considerable peeling had

occurred within six months of the original painting. Preparation for paintins

The entire work inclUding surface preparation and painting was carried out by a painting contractor and his men.

Four houses were stripped of the old paint by

"burning off" with blow-torch and scraper. The p.aint was

difficult to remove completely and in some small areas the

original primer could not be taken off. ,Rough spots were

rubbed down with sandpaper. It was noted that the stripping

was not done as effectively on the gable ends. Apparently

the workmen had difficUlty in carrying out this operation from

a ladder and did not take time to set up a scaffold. There

was considerable scorching and charring of the wood as a result

of the burning-off process. On the whole, howeverg the

stripping was reasonably well done.

Eight houses were prepared by rubbing down the old

ｰｾｩｮｴ with wire brushes and sandpaper to remove as much of the

loosened coating as possible. Removal of. the old paint was

not achieved to any useful extent. The wire brush has poor

13

-Two houses were painted inside with two coats of

aluminum paint to form a vapour barrier. The aluminum paint

was applied on the interior surfaces of the exterior walls

(main floor rooms). A finish coat of ordinary wall paint

was applied over the aluminum.

The steps taken in preparation for outside painting are shown in Table 110

Table II

Preparation for Exterior Painting

House No , I 2 3

4

5

6 7 8 9 10 11 12 Exterior wire brushed burned off wire brushed burned off wire brushed wire brushed wire brushed wire brushe d burned off burned off wire brushed wire brushed Interior

two coats of aluminum paint two coats of aluminum paint

The ｾｯｩｳｴｵｲ･ content of the siding of all houses was checked by means of an electrical moisture meter before

painting commenced. It varied from 8 to 12 per cento

Louvered vents were installed at the peaks in the

gable ends of each house. This work was carried out by CoMoH.Co

Paint

The paints were taken from the regUlar stocks of CoMoHoC. except for two paints which were purchased specially

for the work Ｈｳ｡ｾｰｬ･ｳ

9

and 10).

Samples were taken at the time of application either from the original container or from the spray tank.

14

-Table III List of Paints

.

__

.

-

----_._--Sample N.R.C.

No. No. Colour

ＭＭＭＭＭｾＭＭＭＭｓ｡ｭｰｬ･ s . From ｵｮｯｰ･ＭｮＭ･ｾ､ａＭＭＭｾｆｾｲＭｯＭｭＭＭｳＭｰＭｲＭ｡Ｍｹ container tank 1 2

ｾ

ｾ

7 9

10

10012 Cream x ＱＰＰＱｾ Grey x 1001 Dark green x 10015 Cream x 10022 Cream x 1002ji Grey x 1002 Light green x 10028 Grey x

10028A Light green x

Analysis of the paints was carried out and the results are shown in Appendix B.

Painting ｐｲｾ｣･､ｵｲ･

On the four houses that had been stripped by

blow-torch, the first coat of paint was applied by brush. The

trim on all houses was painted by brush. The remainder of

the painting was done by spray-gun.

The spray painting was fairly well done although there was a certain amount of wrinkling, a common defect when

house paint is applied by spray. The gloss was not as good

as one could obtain by brushing.

The weather was favourable during the first week

when most of the painting was done. Rain fell on several days

during the remainder of the time, as shown in Table IV.

Precipitation at Wrightville, however, is not necessarily the

same as at Rockcliffe, approximately

5

miles away.

Table IV

Weather Conditions during Painting (Recorded at Rockcliffe weather office)

Temperature Rainfall

Date at 1.JO p.m. (inches) Time of rain

Oct. 1,

1948

71

0.47

afternoon

2

₅₇

nil

,

(Sunday)

ｾｾ

nil nil

g

62

nil

69

nil

15

-Table IV cont'd

Tempera ture- Ra

lnfal1---

o

-- --- - "

Date at ｾｾＲＰ p.m. (inches) Time of rain

Oct. 7 71 nil

8 52 0.85 late morning and afternoon

9 60 0.58 late afternoon and evening

10 (Sunday) ₅₅ nil 11 _{52 0.12 afternoon} 12 58 nil

ｩｾ

53 0.16 morning 50 nil 15 58 nil 16 64 0.46 afternoon of 16th until 17 (Sunday)

tt6

0.36 noon of 17th 18 nil 19

Illi

trace afternoon

20 nil

Most of the painting was done under dry conditions but on one or two days some paint was applied in damp weather when the inspector was not present.

The painting schedule is shown in Table V. Table V

----Painting Schedule

__'_..

｟ｍ｟ｾ

__._..

Paint

House No. No. Colour 1st Coat 2nd Coat 3rd Coat

1 ₅ cream _{Oct. 5} Oct. 6 none

2 ₅ cream Oct. 1&1+ Oct. 5 Oct. 7

4

7 light green Oct. 7 Oct. 8 none

5 cream Oct. 5 Oct. 7 Oct. 11

g

10 light green Oct. 1 Oct.

g

none

k

cream _{Oct. 5} Oct. none

7 light grey Oct. 5 Oct. 6 none

8 6 light grey _{Oct. 5} Oct. 6 none

9 7 light green Oct. 7 Oct. 8 Oct. 11

10

₉

light grey Oct. 14 Oct. 16 Oct. 18-22

11 10 light green Oct. 7 Oct. 11 none

16 -Results

The houses were examined at intervals with particular attention to moisture content of the wood, blistering and

peeling of the paint, and evidence of normal weathering such

as chalking and loss of gloss. Results of some of the

inspections are described below:

(a) In Dec. 1948 (two months after painting) moisture

levels in the siding were normal (10 to 14 per cent) in six

houses. The remaining six had 16 to 24 per cent moisture in

some siding boards, usually near the ground.

Moisture content was below 14 per cent in houses 4,

5,

7,

9, 10 and 11. Moisture content was 16 per cent or

higher at some points in houses 1, 2,

3,

6, 8 and 12.

Ratings with respect to dryness are as follows: House No. 1 2

G

£

7

8

9

10 11 12 Dryness Rating Fair Fair Fair Good Good Fair Good Poor Good Good Good Fair

House No.8, which had 24 per cent moisture at one place on the east side, showed some blistering of the paint in this area.

House No.6 exhibited a small area of cracking and peeling on two boards.

There was no other evidence of paint deterioration at this time on any of the houses.

(b) In March 1949 (five months after painting) the

moisture content of the siding had risen to a dangerous

extent in most of the houses. Only three houses had normal

moisture content (10 to 14 per cent). The remaining nine

showed 16 to 24 per cent or more in many siding boards,

mostly close to the ground. In some cases, boards two and

three feet above the foundation had 18 and 20 per cent

moisture. At five feet above the foundation the moisture

17

-Ratings with respect to dryness as at March 1949 are as follows: House No. 1 2

,

6

7 8

9

10 11 12 Dryness Rating Poor Poor Poor Fair Poor Fair Poor Poor Good Good Good Poor Moisture content of bottom boards 21-2.3% 20-24 20-24 15-22 23-24 16-17 19-21 21-23 12-13 9-10 14 20-23

Houses 9 and 10 are situated somewhat above street level and accordingly have better drainage than the others.

The condition of the paint at this time showed

deterioration in small areas on some houses. There was

noticeable blistering on houses 1, 2, 4, 5, 7, 8, and 12. Wherever blistering was visible, the wood had high moisture

content (over 20%). There was some peeling in the blistered

areas on houses 2, 5, and 8. There was no blistering or

peeling on houses 3,

6,

9, 10, and 11. With the exception

of No.3, the moisture content in the siding of these houses

was under 17%. The total blistering and peeling was

relatively slight compared to the total painted area and the general appearance of the houses was good.

(c) At Sept. 1, 1949 (eleven months after painting) the

general condition

ot

the paint on most of the houses was still

good (see photographs, 1949). The siding had dried out during

the summer and moisture content was 10 to 12 per cent in all

houses. In addition to the blistering and peeling in small

areas noted in March, 19Lj.9, there was also blistering on No.3

and slight peeling on 1,

5,

and

6.

The ratings for paint

condition are shown in Table VI.

(d) In Octoberl. 1950 (2h months after painting) there

was considerable peeling of paint on eight of the twelve

houses. Moisture content at this time was normal. It was

apparent that deterioration of the paint coating had been proceeding fairly rapidly during 1950 on these eight houses.

(1,

3,

5,

6,

7,

8,

11, 12).

In comparison with their condition in 1948 (original

paint) houses 1,

6,

11, and 12 had peeled to about the same

extent; houses 2,

3,

4, 7, 8, 9, and 10 were in better

18

-The four houses that had been stripped of the old paint by blow-torch were in better condition than the rest

ＨＲｾ Ｔｾ 9, and 10). House 10, which showed the most peeling

of all in ＱＹＴＸｾ was in good condition and free from blistering

and peeling. House 9 was almost as good. Chalking was

general throughout as would be expected after two years' service.

There was serious peeling on houses 1,

3»

5,

6, 7,

Ｘｾ lID and

12.

Whereas peeling at September

1949

was confined

to small areas near the foundation, damage at the time of

writing was extensive extending to the upper parts of the walls. The course of blistering and peeling is shown in

Table VI. Blistering is transitory and occurs mainly in the

winter and spring months. Blisters were not observed during

the summer and fall.

Table VI

Occurrence of Blistering and Peeling

I

: I

I

\ I

I

T .

--9 1101 11] 12 MI

I

I r : T i 1 i

I

I

T

i

'1. 1

!

J

ｾｉ

7 1 8 i S 6

Tj

I T M HnIH:I

5

I

Slight, Marked, Very Marked

,

I T S

I

S

I

_j 1 S ; , ｾ 3 l

4

! T

I

!

1 t 1 I MI

I

, ; S I 1

s

T 1 . 2 Dec0

1948

!

Blistering

I

Peeling March

1949

Blistering Peeling

! Ratings: Zero» Trace,

!

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _- - J Sept.

1949

Blistering Peeling

I

T Oct.

1950

I

Blistering

I

Peeling VM , i

The condition of the paint with respect to cracking

and peeling is summarized in Table VII. The ratings were made

from inspection of the whole house. The photographs (Figs.

6

to 13) show the east side of every house. Peeling was worst

on the east exposure but occurred to some extent on the other

walls as well. Photographs do not show paint condition in

great detail but serve to record the worst damage. It is

difficult to distinguish between ordinary dirt collection and actual deterioration of the paint coating in a photograph.

19 -Table VII

Summary, Condition of Exterior Paint

Condition Condition Condition

House No. Oct. 1948 Sept. 1949 Oct. 1950

(old paint) (new paint) (two years

(one year) exposure)

1 Poor Fair Bad

2 Poor Good Fair

G

BadPoor FairGood FairPoor

g

Fair Poor

Poor Fair Poor

7 Bad Good Fair

8 Poor Fair Poor

9 Poor Very Good Good

10 Bad Very Good Good

11 Poor Good Poor

12 Poor Good Bad

IT'otals: Good 0 Good 7 Good 2

Fair 0 Fair 5 Fair ₃

Poor 8 Poor 0 Poor 5

Bad ₃ Bad 0 Bad 2

(Ratings: Good, ｆ｡ｾｲＬ Poor, Bad)

Discussion of Results above.

primary problem

Useful conclusions can be drawn from the data given The following discussion is related to the three

objectives of the work (page 11) and to the general of moisture control.

It is fairly clear that peeling has been caused by two separate conditions, (a) excessive moisture in the siding, resulting in blistering and peeling, (b) application of the

new paint over old paint that has lost most of ｩｾｳ ｡､ｨ･ｳｩｯｾＮ

In addition there has been some peeling where the lumber is of very poor quality.

(a) Complete stripping of paint versus wire brushing.

"

There is a clear superiority in paint durability on

houses 2,

4,

9,

and 10, which were stripped by burning off,

over'the remaining eight houses which were wire-brushed. No.7 is a possible exception.

20 -Table VIII

Summary, Burning Off vs Wire Brushing

Burned off Wire brushed

No. Condition, Oct. 1950 No. Condition, Oct. 1950

2 Fair 1 Bad

4

Fair ₃ Poor

9

Good 11 Poor 10 Good 12 Bad

g

Poor Poor 7 Fair 8 Poor

It is evident that the old paint had lost its adhesion and did not provide suitable anchorage for a new

paint job. There was relatively little peeling during

1949

while the new paint remained fairly flexible. During the

second summer

(1950),

the old paint lost its adhesion over

large areas and both coatings peeled off together.

In addition, there was some peeling in the lower boards near the foundation because of excessive moistureo

Houses 2 and

4,

which had been burned off, showed this

condition to some extent. House 2 showed some peeling also

in the upper part of one wall, believed to be due to inadequate

stripping in this area (see page 12). On the whole, however,

the four houses that were stripped show much better paint durability than those that were not stripped.

(b) Paints from CoMoHoCo stocks versus specially=chosen paints.

A first-grade paint of well-known brand was purchased

at retail and used on houses 9 and 12. CoMoHoCo stock paints

were used on houses 10 and 110 One house of each pair had

been stripped by burning off. The results (Table IX) indicate

that both paints had good durability on a well-prepared surface but poor durability over the old insecure coatingo

Table IX

Summary, Comparison of Stock Paints with Paint Specially Purchased Stock Paints

House No. Condition,

Octo

1950

Specially purchased

House Noo Conditions

Oct.

1950

9

(Burned off) 12 (Wire brushed) Good Bad

10

(Burned off) 11 (Wire brushed) Good Poor

21

-(c) Aluminum paint on interior walls as vapour barrier versus no special treatment of interior walls.

The interior walls of houses

5

and 7 were given two

coats of aluminum paint. Houses 6 and 8 were maintained as

controls. The results were inconclusive. House

7

was

superior to the others in durability but House

5

was not

(Table X).

Table X

Summary, Effect of Coating Interior Walls with A1UL1inum Paint

6 8 PoorPoor (all wire-brushed)

5

7 Poor Fair

House

7

showed a moderate amount of peeling. In order to

determine the value of the interior paint as a vapour barrier, it would be necessary to carry out the experiment with new houses or after complete stripping.

(d) Moisture control.

It is evident that accumulation of moisture in the siding is a problem in most of the houses (see page 17). High moisture content, blistering and peeling were observed

in the lower boards of several of them, e.g. No.1, 2,

5, 6,

and 8. Some of the moisture probably comes from the ground

but it may also come from within the house and from penetration

of rain through the joints of the siding. The moisture content

is highest in the early spring and blistering occurs at that time0

There was no evidence of high moisture content or

blistering in the upper part of the walls during the inspect:i.ons. These conditions were confined to a level less than five feet

above the foundations. Possibly the vents installed in the

gable ends took care of the .moisture in the upper part of the

house. Ground moisture may be asswned to be a major factor in

the durability of the paint on the lower part. Accordingly,

it may be necessary to effect better ventilation of the crawl space and reduction of ground moisture to eliminate blistering and peeling on the lower boards.

The extensive peeling of the original paint prior to

this investigation may have been caused by an all-over ｡｣｣ｵｭｵｾ

lation of moisture. Such accumulation seems to take place during

or shortly after construction. Further study of this condition

22

-Conclusions

1. When extensive peeling has occurred, it is essential to

remove all of the old paint before re-painting. Otherwise

further peeling is very likely to take place.

2. Some of the houses in this project show excessive moisture

accumulation in the siding, mainly near the ground. This

condition, unless corrected by improved ventilation, drainage, or moisture barriers, will continue to cause peeling of paint applied to the siding.

3.

Careful re:)ainting, including burning off of old paint,

use of good quality paint and good workmanship, will not prevent subsequent blistering and peeling if the walls

of the house are allowed to accumulate moisture (Houses 2

and

4).

ｾＮＮ When repainting is carefully done, with the precautions

listed in the preceding paragraph, there is every indication that normal paint durability will be obtained, provided

ｾ 23

-BIBLIOGRAPHY

Adhesion in the painting and in the glueing of wood. F.L. BrowneG

UG So Forest Products Laboratory Report No. R977. Indus. and

Eng. Chem. v. 23, nG 3, March 1931, p.290-294.

Aluminum coatings for moisture proofing wood. U. S. Forest

Products Laboratory Technical note 228. Revised Aug. 1940.

Condensation control in dweLl.Lng construction. U. S. Forest

Products Laboratory in collaboration with the Housing and

Home Finance Agency. H.H.F.A. unnumbered report. 1949.

73p.

Condensation in buildings. Richard S. Dill. U. S. National

Bureau of Standards. Letter circular LC 863. June, 1947.

17 p ,

Condensation in walls and roofs. R.R. Britton. Housin8 and

Home Finance Agency Technical paper No.8. April 1948. 21 p.

Condensation in wood frame walls under variable state conditions

of exposure. RoR. Britton and R.C. Reichel. Housing and

Home Finance Agency Technical paper No. 12. June 1949. 51 p.

Condensation problems in modern buildings. L.V G Teesdale.

Uo So Forest Products Laboratory Report No. Rl196. 1941.

9 pG

Condensation within walls. FoB. Rowley, A.B. Algren, and

CoEG Lund. Heating, Piping and Air Conditioning v. 10, nG ｬｾ

Jan. ＱＹＳＸｾ ｰＮＴＹｾＶＰＮ

Crawl spaces. R.Ro Britton. Housing and Home Finance Agency

Technical bulletin No.2. Jan. 1948. p.17-39.

Diffusion in wood. H.K. Burr and A.J. Stamm. U. S. Forest

Products Laboratory ｭｩｾ･ｯｧｲ｡ｰｨ･､ report R1674. Jour. of

Physo and Colloid Chem. v. 51, n. 1, Jan. 1947, ｰｇＲＴｯｾＶＱＮ

Effectiveness of paints in retarding moisture absorption of

wood. FoL. Browne. Uo S. Forest Products Laboratory Report

Noo R974. Indus. and Eng. Chem. v. 25, no 8 , Aug. 1933,

pG83S=842.

General information on wood paints and coatings. R.C. Hubbard.

Canada, Forest Products Laboratories mimeograph No. 0-150.

Dec. 1949.

7

p.

Linseed oil films. Notes on permeability, absorption and

solubility. HoF. Payne. Ind. and Eng. ChemG v. 32, n. 5,

24

-Manual on the selection and use of paints. Ed. by C.Y. Hopkins.

Canada" National Research Council Report No. NRC 2111. 1950.

43 p.

Moisture condensation in building walls. H.W. Woolley. National

Bureau of Standards Building Materials and Structures Report

BMS 63. Dec. 1940. 14 p.

Moisture permeabili ty'p diffusion and sorption in organic

film-forming materials. A.M. Thomas. Jour. Applied Chemistry

v o ｬｾ n. Ｔｾ April 1951, p.14l-l58.

Paint blisters and Why they form. B.L. Grondal. Wood Construction

and Building Materialist. Pub. by Wood Construction Publishing

ｃｯｭｰ｡ｮｹｾ ｘ･ｮｩ｡ｾ Ohio. Oct. 1949.

Paint manual for the control of paints and painting. Uo So

Department of the Interior, Bureau of Reclamation, Denver.

April 1951. 203 p.

The painting of exterior wood surfaces. Uo S. Department of

Commercep National Bureau of Standards, Washington, ｄｾｃｯ

Letter circular No. LC 810. Nov. 1945. 8 p.

Paints as moisture barriers. A.C. Elm. Official Digest, Fed.

of Paint and Varnish Production Clubs, n.267, April 1947, po197-228.

Passage of liqUids" vapors and dissolved materials through

softwoods. AoJ. Stamm. U. S. Forest Products Laboratory

Technical bulletin 929. Oct. 1946. 80 p.

Permeability of building materials to water vapour. JoD. Babbitt.

Heatings Pipings and Air Conditioning v. 10" n. 11, Nov. ＱＹＳＸｾ

p.751=755.

Permeability of paint films to moisture. R.I. Wray and

AoR. Van Verst. Indus. and Eng. Chern. v. 25, no 8.p Aug. 1933,

p.84c>846 o

The permeability of protective coatings to water vapour.

RoEo Lishmund and FoJ. Siddle. Jour. of the Oil and Colour

Chemists' Assoc. Vo 24, 1941, p.122-l37.

Permeability to moisture of organic surface coatings. Henry

Fleming Payne. Induse and Eng. Chern. (analytic al edition)

v. I I i Aug. 1939, p.453-458.

Porosity of paint films; adsorption studies of unsupported

linseed-oil films. Irvin Wolock and B.L. Harris. Indus.

and Eng. Chern. v. 42" JUly 1950p p.1347-49.

The program of paint maintenance for the frame house.

FoL. Browne. U. So Forest Products Laboratory Report No. Rl127.

25

-Relation of permeability to moisture and durability of paint

systems. W.W. Kittelberger. Indus. and Eng. Chem. v. 30,

no 3, March ＱＹＳＸｾ p.328-333.

Remedial measures for building condensation difficulties.

L.Vo Teesdale. U; S. Forest Products Laboratory Report

R1710. Sept. 1947. 26 p.

Repainting the paint-neglected house. ｆＮｌｾ Browne. Uo S.

Forest Products Laboratory Report No. Rl136. 1935. 10 p.

Report on the examination of paint on the exterior of houses

in the Vancouver area. C.Y. Hopkins and E.V. Gibbons.

National Research Council, Division of Building Research

Report R=l. Oct. 1948. 23 p.

Some causes of blistering and peeling of paint on house

siding. FoLo Browne. U. S. Forest Products Laboratory

Report No. R6. March 1933. 10 p.

Studies on the permeability of bouse paints. A.W. Van Heuckeroth.

National Paint, Varnish and Lacquer Association. Scientific

Section Circular No. 597. March 1940. 7 p.

Suggestions on overcoming construction defects and other

factors that cause paint failure on wood surfaces. H.A. Gardner.

National Paint, Varnish and Lacquer Association. Circular

No. 723. Dec. 1947. 31 p ,

Temperature dependence of water vapor permeability of organic

polymer films. Bibliography. P.M. Doty, W.H. Aiken, and

H. Mark. Indus. and Eng. Chern. v , 38, Aug , 1946, p.788-791o

Testing house paints for durability. F.L. Browneo U. So

Forest Products Laboratory Report No. RIOll. Jour. Chem.

Education v. 10, n. Ｙｾ Sept. 1933, p.529-38.

Two coat system of house painting. FoLo Browne. U. S. Forest

Products Laboratory Report No. R1259. Revised 1950.

Vapor resistant coatings for structural insUlating board. FoBo ｒｯｷｬ･ｹｾ MoHo Lajoy, and E.To ｅｲｩｾｫｳｯｮＮ University of

Minnesota Engineering Experiment Station. Bulletin No. 25

v. 49) n. ＳＶｾ Sept. 15, ＱＹＴＶｾ 31 po

Water immersion testing of metal protective paints; role of

osmosis in water absorption and blistering. WoW. Kittelberger

and ａｾｃＮ Elm. Indus. and Engo Chern. v. 38, n.

7,

July ＱＹＴＶｾ

p.695,-699.

What can be done to make paint maintenance more successful.

ｆｾｌｯ Browne. Uo So Forest Products Laboratory Report

26

-When and how to paint homes and farm buildings.

Uo S. Forest Products Laboratory Report R962.

14

p.

F.L. Browne. May 1938.

Wood properties and paint durability. F.L. Browne. U. S.

Forest Products Laboratory miscellaneous publication 629.

July 1947. 10 p.

Wood properties that affect paint performance. F.L. Browne.

Uo So Forest Products Laboratory Report No. Rl053.

CENTRAL MORTGAGE AND HOUSING CORPORATION - PAINT DATA (EXTERIOR) C.MB.C. 419A

House No. ｾ Street ---.Project No. - ---.Municipality Province PaintingContractor,

AGENERAL

I

1. Report on five houses for each painting contractor

-

1 2. In addition to forms required for Regional and

INSTRUCTIONS I in anyone project. Branch Offices, complete three forms for Head Office for each house.

3. Identifyall materials by typeor brand and

manu-facturer.

-

ﾷﾷ｟ＭＭＭＭＭＭＭｉＭＭＭＭＭ］］ｾ］

IB

i_ WALL 11.Vapour Barrier.

,CONSTRUC-TION: 2. Insulation I . I3. Sheathing. ! TYPE OR BRAND ---ＭＭＭＭＭｾＭＭＭＭｉＭＭＭＭ

MANUFACTURER _{Wall Construction (Continued)}

4.Experior Finish Materials

(i) Walls, main.

(ii) Decorative Panels or Bays (iii) Walls, gable

(v) Trim, sash, etc.. (iv) Doors

(vi) Porchftoors.

TYP& OR BRAND MANUl'ACTURBR

Ｎ｟ＭＭＭｾＭＭ

PAINTING D Ih.,.r.llATUIUI: (LOW) IPOP: Ir.'RAIN' WlTRm 72 HOUR! BuoaaIlJ'Fouo.DunDuRlNO PUNTlriO

An I P"lNTINQ A...O 6 HooRS IOR 24 HotnUIMTa.Jt CoAT (OItTAI1) I AJ6> DM.YJHG (Da1'AlL)

- - - I DaYINO 1 _

E 1. Primer or Sealer_1 _

PANELS 2. Second Coat .

or BAYS 3. Third Coat.

---iＭＭＭＭＭＭＭＭＭＭＭｾ

»

_•

...

._._.__.__ ._--1. " ._ _ '- ---,. .-._._--.- ' -_.---_..

__

._---_.. I DOORS s PORCH fLOORS

G I L Primer or Sealer

I·- ._. -

i··

_.---1---1---ｊｧｾｾｾｳＩ ｩｾＺ ｾｾｾｾ､ｃｾｾＺｴ ｾ］ｾ

_

ＭＭＭＭｾ］ＭＭ

-:

-=-=-===-

ＭＭＭＭＭＭｾＭＭｉ

-.:.-=.--=-= \

ＭＭＭ］ＭＭＭ］ＭｾＭＭｾＭ］ＭＭＮＭＮＺＭＮＮＺＺＮ］］ＭＭＭＭＭＭＡ :::--==-

--===-=---==--=-:.::

1---H

I

ｾＭ ｾﾷｮｭ･ｲｯｲｓ･｡ｬ･ｲ

--- - ---- 1- - -

---1--- ---1-- -

ＭＭＭＭＭＭＭＭＮＭＭｉＭＭＭＭＭＭＭＭＭＭＭＭＭＭＭＭＭＭＭＭｉＭＭＭＭＭＭＭｾＭＭＭＭＭＭＭｉ

SASH ｬｾＺ ｾＧ｣［ＺＧＬｾｾｾｾｾｾｴ ｾｾＭｾ __.:

i.==---==----T-

｟］ｾｾＭＭ］ＭｾＭＭ］Ｚ

-==

-=--!

ＭｾＭ

- - --

ＭＭＭＭｾ］］］｟］］ｉＭＭＭＭＭ］ｾＭ］ＮＺＺＮＭＭ］ｾＮＺＺＭＭｾＭｾｾｾＭ］ＭＭＭＭＧ

F I' 1. Primer or Sealer.

TRIM 2. Second Coat

CENTRAL MORTGAGE AND HOUSING CORPORATION PAINT DATA (INTERIOR) C.M.H.C. 419B House No. Street Project No. Municipality _ ___Province Painting Contractor _

A

GENERAL 1. Record the same houses chosen for recording

ex-2. In addition to forms for Regional and Branch _{3. Identify all materials by type or brand and} manu-INSTRUCTIONS terior painting in all projects. Offices, complete three forms for Head Office for each_house. facturer,

B WALL CO:\TSTRUCTION: TYPR OR BRAND MANUFACTURER MATERIALS, INTERIOR FINISH: TYPE OR BRAND I MANUFACTURER

i 1. Insulation _---,--- - ＭＭｾＭＭＭＭＭＭ｟ ..__._-_.- I. Sash. -2. Trim ... 2. Vapour Barrier - - - _..- - - ' -- - , . - -3. Stair handrails. - -3. Wallboard._ t.·· ...- - - -.._ - - - - -｟ Ｎ ｾ Ｎ Ｍ -4. Floors --_.

---(i)Bathroom, Kitchen (dado) - - - ---_..---,--..-.- --- - -

-(ii) Other Wallboard (walls). 5. Kitchen counters. - - _- --- ----

--- _ . _ --- --- --- , . _ --- --- --- --- --- --- --- --- ---

-6. Kitchen cabinets _

(iii) Other Wallboard (ceilings) - - - Ｍ Ｍ Ｍ Ｍ ｟ Ｎ ｟ Ｍ Ｍ Ｍ ｾ Ｍ -

--7. Doors . -.. i

MANl:FACTUJUtR PAINTING

D Preliminary Treatment Taped Joints:

BRUSH OR! TYrs OR BaAND

I

I SPRAY I - - - I -WIl: ....THER--RJ\IN. Foo, OUST INTBRIOR T&.IilPBUTUltB AT8.00 A.V. AaTIPIClAL HEAT AT 8.00 A.II. (Y!!:S OR NO) E BATH-ROOM I F

- I

KITCHEN I i G LIVING ROOM 1 Primer, sealer. 2 Walls, second coat. 3 Dado (if any) second coat. 4 Ceiling second coat.

1 Primer, sealer. 2 'Walls, second coat .. 3 Dado (if any) second coat. 4 Ceiling, second coat

1 Cciling 2 Walls. ｾ

•

ｾ -ＭＭＭｉＭＭｾＭＭＭＭ --- -1---1---1---- -+--ＭＭＭＭｉＭＭｾＭＭＭＭＭＭＭｉＭＭＭＭＭＭｉＭ - - - - I

---

ｉＭ｟Ｍ］］］ｃ｟ＭＭＭ］］Ｍｾ｟ 1 1 1 ---- - - 1 - - - 1 - - - 1 1 - - - - 1

i=

Ｍｉｾ

ＭＺｾ ｉ］ＺＺＭｾＭｾｾｾ］ＭＭ］､ＭＭｾＭｬｾ］Ｍ］ｬＭＭｾＭ］ｾｬ］］Ｚ］］Ｍ］Ｚ

----==:.--

ＭＮｉ］ｾＭ -=----=---==---=ＭｾＭＭ］ Ｍ］ｾＭﾷｉ

Ｇｾ｟ｾ

__

Ｍ］Ｚ［ｾＱｾｾｾｾＱ］Ｐｾｾｾ［］Ｚｾｾｾ］Ｍｾ］ｾｾｾＭＭ］ＧＭ

ＭｾＭ Ｍｉ］ｾ

__

ｾ

ｾｉ］］ｾ

ｾｩｾｾＭＺＭ

-:_--

ｾＺＭｾＭＭＭｉＭＭ

1 - - - 1 - - - - 1 1 Ceilings 2 Walls.

1 Bedroom No. I, ceiling. 2 Bedroom No. I, walls .. 3 Bedroom No.2, ceiling .... 4 Bedroom No.2, walls .. 5 Bedroom No.3, ceiling. 6 Bedroom No.3, walls.

1 Sash, Primer

2 Sash, second coat 3 Sash, third coat. 4 Trim, primcr. 5 Trim, second coat. 6 Trim, third coat .

7 Doors,primer 8 Doors, second coat. 9 Doors, third coat ... 10 Main stair handrail filler. 11 Main stair handrail varnish. 12 Floors, first coat ... 13 Floors, second coat 14 Kitchen counter, first coat. 15 Kitchen counter, second coat. 16 Kitchen cabinets, first coat. . 17 Kitchen cabinets, second coat. 18 Kitchen cabinets. third coat OTHER FINISH I BED-ROOMS J H HALLS

APPENDIX B Composition of Paints

The paints from CoM.H.C. stocks were judged to be

of fair quality on the basis of the analytical results. They would be expected to give two to three years' service

under normal conditions.

They were evidently lower in cost of manufacture

than the paints purchased at retail for comparison. The

pigment composition reflected the supply situation prevailing

at the time. Zinc oxide was present in larger proportion

than usually considered desirable, while white lead and

titanium oxide were in correspondingly lesser amounts. The

content of extender pigments in four of the paints was higher than would be expected in a first-grade paint of similar

formula.

Analysis of scrapings of the original paint,

applied in 1946 (House No.9), showed a pigment composition

of fair quality. It is not likely that the quality of this

Fig. 1--1948

Fig. 2--1951

823

Churchill Street

Fig.

3--1948

Fig.

4--1951

833

Churchill Street

Fig. 5-- Mi ldew on exterior siding of house in Nor t h Vancouver, February, 1951.

•

Fig. 6--0rigina1 pa int on Hous e No . 10, badly

peeled. It was str ipped off and

re-pain te d (1948).

ｾｩｧＮ 7--House No. 10, two years after

re-painting (1950) . There has been

no peeling.

Fig. 8--Peeling on bottom boards below floor level, evidently due to ground moisture accumulating

in the crawl space. House No.6. (1948).

Fig. 9--Typical peeling of original paint on House

No.4.

It was stripped off and re-painted. (1948).

Fig. 10--Section of House No.4, two years after re-painting (1950).

-==

］］］］

］］Ｍ ］］］］］］

ｾ

ｾｾ

=-I. ｾ -ｾｾ _. .｟ＭＭＭｾＭＭＭＭＭ ＭＭＭＭＭＭＭ ｾ ｾ ｾ ＭＭＭＬＮ Ｍ ｾ ｾ 1ｾ｟ｪ_{ＮＮＬＮｾＮＮＬ} .Ｎｉ［ＮＮｾ ＧｒｱｾｮＢ ｾＮ .. .../ ' .. . _ • •ｾ I

Fig. 11--0riginal paint on House No.1. It was wire-brushed and repainted (1948) •

/ . /

---

-

---Fig. 12--House No.1, in good condition one year after re-painting (1949).

Fig. l)--House No.1, two years after

re-. painting. Painting over the old,

insecure coating has resulted in

peeling of both coats. (1950).