|Home Skills and Basics Wallpaper Home & Domestic Interior Decorating Professional Decorating|
A lot of very interesting material here as well as a lot of the expert skills which have been lost over the years. If you are a serious professional decorator then these pages can only enhance your skills and give a deep understanding of your trade.When we remember that the average paint coating is only about 1/1000th inch in thickness and we consider, at the same time, the number of different factors on which its durability depends, we may well wonder, not that failures and defects sometimes occur, but that they do not take place far more frequently.
The choice and mixing of the necessary materials, the nature and preparation of the surface, the skill and experience of the operative, and the atmospheric conditions before, during, and after application are all points of vital importance, and negligence or lack of care in anyone of them may materially affect the life of the paint.
There is no doubt that far too much is expected of the painter.
It is his misfortune that he is the last man on the job when a new building is under construction, and that, most unfairly, he is expected to make good, or to conceal, the shortcomings of other tradesmen, or the deficiencies of their materials.
Even if the plasterer leaves a wall uneven or the carpenter fails to use his plane as thoroughly as he should, the painter is nevertheless supposed, in some mysterious manner, to produce a first-class finish.
Only too often, under present-day conditions, he is confronted with surfaces, such as new and damp Portland cement or woodwork full of knots and sap, which it is extremely difficult, if not impossible, to paint with any guaranteetee of success; yet he will probably be held responsible for any breakdown in the paint film which may occur.
The situation is further complicated by the widespread and increasing use of proprietary materials which are frequently specified by the architect or owner without adequate knowledge of their performance or of the circumstances in which they are to be applied. |
The unfortunate position in which the present-day painter finds himself on too many occasions was well summarized in a Bulletin issued by the Building Research Station in 1934 on the effects of building materials on paint films. "The decorator," observed the Bulletin, "is seldom fully informed with regard to the exact type of plaster which has been used, the nature of the backing material, the facilities which have been given for drying, and other essential details.
More frequently, he is simply required to cover a given surface with a specified paint as quickly as possible and he may not find himself in a position to object to such conditions."
Certain defects in painting work are inevitable that is to say, they are due to circumstances which could not have been anticipated and against which it would not have been reasonable to take special precautions.
Rain or fog may suddenly occur while outside work is drying; structural defects in a building may lead to the presence of moisture in a wall, to the detriment of the finish; painted metalwork may be exposed to an abnormally high temperature; conditions such as these will impose a greater strain on paint, no matter how good or how carefully applied the latter may have been, than it can bear, and it would be unreasonable to blame anyone for the breakdown.
Responsibility for Failure
In the great majority of cases, however, the premature failure of a paint -and in this term are also included enamel, varnish, water paint, and other forms of finish-can be traced to some fault of omission or commission on the part of someone, and as the failure will probably have to be made good and this will cost money, it will often be necessary to determine on whom the responsibility must be placed.
The persons directly or indirectly concerned will be the manufacturer of the offending material, the decorator who applied it, and, on occasion, the architect or even the property owner who specified it.
The Manufacturer .-Of these, the responsibility of the manufacturer will be limited to such of his products which fall short of the description he applies to them, or fail to fulfil the functions he ascribes to them.
It is only natural that sometimes, when a job goes wrong for no very apparent reason, the decorator should blame the material rather than his own workmanship, but before he does so he should make certain that not only has a product of the right type for the work in question been employed, but also that the instructions of the manufacturer regarding its application have been scrupulously followed.
This is especially important in view of
the enormous increase in ready-mixed paints, and also because of the introduction of new forms of finish with which the decorator is not acquainted. |
For example, for very many years it has been an established trade practice to thin out oil paint with linseed oil or turpentine -should it become too thick to put on with ease.
From the judgment given in a famous lawsuit at Plymouth in 1933, however, it would appear that any such adjustment to a proprietary paint is made entirely at the decorator's risk unless it is expressly recommended or permitted by the manufacturers (Harris & Sons v. The Plymouth Varnish & Colour Co., Ltd.).
It may be observed that, thanks to modern methods of manufacture and the careful supervision exercised in all factories of repute, very few faulty materials are despatched.
Moreover, owing to the systematic check on the constituents used in each batch of paint or other product, it is usually comparatively simple for the manufacturer to determine the cause of failure, should this be due to any shortcomings on his part.
In point of fact, however, the vast majority of painting defects which occur to-day arise, not from the material, but from other causes which may not necessarily be within the control of the decorator.
The Architect.Many contracts will be carried out directly between the decorator and the property owner, but, on occasion, an architect will be in charge and a paint failure may be due entirely to an unsuitable specification drawn up by him.
He cannot reasonably be expected to have expert technical knowledge of painting, which is, after all, only one of twenty or more different trades carried on under his control; consequently his specifications are not always as satisfactory as they should be.
Either he relies on the claims made by manufacturers for their own materials or else he will probably fall back on rather vague and stereotyped instructions which mayor may not be suitable for the work in progress.
The relationship between the architect and the decorator at the present time cannot be said to be entirely harmonious and there is unquestionably need for far closer collaboration.
Some architects, it is true, will regard the decorator as an expert in his own particular line and allow him con siderable latitude in the choice of materials and in the method of applying them.
Others, on the other hand, will lay down hard-and-fast rules with regard to products and processes and will pay little or no attention to any amendments or improvements which the experience of the decorator will lead him to suggest.
If the architect ignores sound advice tendered to him in this manner and insists on having an inappropriate specification put into effect, the responsibility for any subsequent failure must obviously fall on him.
Most owners of property have the good sense to allow the decorator working for them a free hand, but there are occasions when they see fit to intervene.
There has been a tendency, of recent years, for the manufacturer to advertise direct to the public, with the result that impressionable householders will sometimes demand that a certain product be used. If the decorator knows nothing of the material in question or has reason to believe that it would be unsuitable, he should take the earliest opportunity of disclaiming any responsibility. for the result.
The Decorator.-The lion's share of the responsibility must fall on the painter, and no better summary of his position could possibly be given than the following extract from a Paper on "Painters' Complaints," read before, the Incorporated Institute of British Decorators on September 20th, 1933, by Mr. James Lawrance, one of the ablest and best-known authorities on paints and painting in the country :
" While the manufacturer must perforce make paints for average or normal conditions, the painter is continually faced with problematical situations.
If he is called upon to paint new woodwork, there is the possible risk of subsequent shrinkage or blistered work, owing to the imprisonment of moisture.
If new cement, chemical activity may assert itself or unsuspected moisture may cause subsequent damage.
When humidity is low, for instance, and the surface is being robbed of its moisture very quickly, it often looks dry, although the underlying bulk of the cement or plaster is actually wet. When previously painted work needs repainting, there may be a host of hidden troubles beneath a fairly innocent surface, and new paint often wakes up old troubles.
There are, in this country to-day, thousands of window sashes and doors that have been painted from the woodwork upwards with unsuitable paint, which has given results that pass muster for a time, but which will, just as surely, give way under subsequent treatment, no matter how well the work is done or how good the paint.B A feeble state of adhesion between the paint and the wood is just able to support a thin compound film for a time, and its appearance will not make Its technical deficiency very obvious.
The painter who has to deal with such work as this is faced WIth the risk of a general breakdown on this ground, which will carry destruction to his own work and probably bring him a letter of complaint is, therefore, part of the painter's business to study building materials and painted surfaces critically.
He may not be able to exercise any control as to the use of these materials in building, but he would incur liability if he failed to point out to his customer defects in the surface which would interfere with the success of his work, if carried out in the specified manner.
He would also be taking a considerable risk of being held responsible if he continued to use materials that were obviously defective or unsuitable for any particular work.
It is very doubtful whether a plea that the material was specified would save him, if he were obviously aware, during the process of application, that the paint were defective.
In any case, such a practice would be unsound, because the painter would be guilty of deliberately adding to the expense of finally rectifying the trouble.
He is expected to be a skilled craftsman, and, as such, he cannot excuse himself if he executes work in the full knowledge that it will fail.
Indeed, it is part of his undertaking to see that the paint is carefully arid properly applied, and, of course, any deficiency in this respect renders him directly responsible.
" He must also make himself familiar with painting conditions, and will probably be held to be negligent if he executes work under atmospheric or other conditions that obviously prevent success.
A bad case would be that of painting over frost or wiping off raindrops with a damp rag and immediately applying paint.
Painting damp surfaces of any kind is an obvious fault, but under some circumstances it may be quite as risky to paint on a sunbaked flank when the thermometer is standing at about 90 degrees in the shade.
This may be possible, however, if a suitable paint is used or if certain modifications are made to suit the conditions.
But, do as he will, the. painter cannot always estimate exactly the forces for good or evil in the surface to be painted.
Neither can he be expected to prophesy the weather conditions."
From the above, it will be realised how hard, on occasion, it may be to determine who is to blame in the case of failure, and when resort has been had to the machinery of the law, the results have been costly and not always conclusive.
The fact of the matter is that painting practice and professional standards vary so greatly in different districts and with different Individuals that on many points it is possible to produce experienced and reliable witnesses with entirely conflicting views.
In the Paper from which we have quoted Mr. Lawrance advocated the formation of a panel of experts who would be prepared to arbitrate in the disputes which concern painting, and there is no doubt that the existence of some authoritative body would be an immense advantage to manufacturers and to decorators alike.