print

American Paint History V

In regard to historic restoration, most frequently the project goal is preservation or rehabilitation. Because of the impracticality of replicating historic paints, restoration is least often undertaken. Given current restrictions for the use of toxic ingredients, such as lead and solvents, contemporary substitute paints using safer ingredients need to be used. Many paint companies make acrylic paints in colors that are close to historic colors as well as appropriate gloss levels, but contain no white lead and no hazardous volatile organic compounds. This is the fifth and final excerpt in this series of American Paint History.

Choosing modern paint types & finish coats

In American Paint History, we considered the ingredients of early, historic interior paints including the pigment, binder, and vehicle, as well as lead, oil and water based products.

In the 2nd installment, American Paint History II, we featured information on Early American paints produced prior to 1875.  We considered some details of historic interior paints and provided background information about some of the types of paint, which were used in the past.

The 3rd installment of American Paint History III discussed factory-made paints after 1875, paint coating investigation, preservation and restoration.

American Paint History IV focused on what causes damage to historical interior paints, appropriate surface preparation and priming for professional restoration.

Restoring decorative painting Photo: NPS files

Work on historic properties generally requires the services of a qualified paint professional who has had at least five years of experience and who can list comparable jobs that a potential client can see. Then, too, getting a sample or a mockup of any special work may be advisable before the job starts. While less experienced workers may be acceptable for preparing and priming, it is wise to have the most experienced mechanics perform the finish work.

Oil-based/alkyd paints

Today’s version of oil paint may have a binder containing some linseed oil (read the paint can label), but also has one of the improved synthesized oils, frequently soy-based, known as alkyds. They dry hard, have flexibility, and discolor far less than linseed oil. They can also be manufactured to dry with a high sheen, and can take enough tinting pigment to create even the very deep Victorian period colors. However, they all contain volatile organic compounds, and thus may be restricted by law in some parts of the United States. They are also less simple and more dangerous to use, as cleaning brushes involves flammable solvents, like mineral spirits.

Acrylic waterborne paints (latex)

Acrylic paints are synthetic resins carried in water. Before the paint dries or cross-links, it can be cleaned up with water. Early in the history of latex paints, some contained styrene/butadiene resins. Now nearly all top-grade latex paints contain acrylic resins, which are superior. Also, until fairly recently, the latex paints, while offering great strength, quick drying, and water cleanup, had some disadvantages for jobs which needed to have an historic look. In addition, latex paints often have excellent color retention with very little fading. Still, it is always a good idea to buy a quart and test the color selections on site before making a total commitment.

Calcimine/whitewash

Modern water based paints such as calcimine can be purchased today and has much the same appearance as the early ones. The same is true of modern whitewash, although today’s whitewashes do not leave the same ropy surface texture as the early ones.

Glazes

Glazes were often part of historic paint treatments. Traditionally oil and turpentine, sometimes with a scant amount of pigment, today’s glazes can be formulated with a water base and are relatively simple to apply by brush. An experienced decorative painter should be consulted before deciding whether to use a glaze coat rather than a high-gloss enamel. The glaze is capable of providing protection as well as a more accurate historic appearance that includes a greater depth to the finish.

Epoxies/Urethane

These were not available until relatively recently and thus are not appropriate for replication of traditional finishes.

Applying interior paints

Because flat wall surfaces generally dominate an interior painting job, some flexibility in applicators is suggested below:

Brushes

Natural bristle brushes now have competition from synthetic brushes made of nylon or polyester which work well for applying either oil/alkyd or latex paints. Being harder than natural bristles, they tend to last longer.

Photo: Paint Quality Institute

Since brushes come in a wide and very specific variety of types suited to different types of work, it is important for the professional to select the appropriate brush for the paint specified for each portion of the project. One strong advantage of brushing paint on is that the paint is forced onto the substrate and into all of the surface imperfections. Thus an expert brushed on application may last longer if the substrate is sound and the primer and finish coats are compatible and of top quality.

Rollers

There is no harm in using a roller, or even an airless sprayer, to apply a prime coat to a large flat area. Since all contemporary commercial paints dry with a smooth surface anyway, use of a roller or sprayer is acceptable for priming, and even for a first finish coat. However, to get paint well pushed into articulated surfaces and to add some texture to larger flat surfaces, a brush final coat may be best.

Photo: Paint Quality Institute

Types of Modern Paint

Oil-based / alkyd:

Nonvolatile oils and resins, with thinners (Alkyds are synthetic, gelatinous resins compounded from acids and alcohol) accept almost any type of coloring/hiding pigments an may be used on interior wood and metal surfaces.

Acrylic waterborne paints (latex):

Typically are made via the suspension of acrylic resins in water, with other resins, plus hiding and coloring pigments and extenders that dry by evaporation. Commercially produced acrylic or latex enamels are also available in a complete range of gloss levels which are produced with the addition of various acrylic polymers and used on interior plaster especially.

Enamels:

Modern alkyd paints are adjusted with the addition of synthetic varnishes to produce a complete range of gloss levels.

Metal finishes:

Paints marketed for use on ferrous metals, can either be alkyd, acrylic, or epoxy based, or combinations. If metal is exposed, only primers formulated with rust inhibitors should be used.

Special finishes: finishes such as urethane and epoxy-based paints may provide a very high gloss appearance and offer superior abrasion resistance.

Finally, decorative paint work in an historic interior– whether simple or high-style–is well worth preserving or restoring, and when such fancy work is being undertaken, traditional tools should always be used. To simplify by using shortcut methods or rejecting painted decoration is indeed to dismiss or skew history as well as to lose the wonder of a true, artistic and historic finish.

Summary

First, it is most important to understand the range of approaches and treatments and to make choices with as much knowledge of the original and subsequent historic paints as possible, using the Secretary of the Interior’s Standards for the Treatment of Historic Properties as a framework.

A paint’s patina of age expresses decades or centuries of endurance in the face of changing climate and conditions. Documenting the sequence of interior paint layers and protecting this information for future investigation should be an integral part of any historic preservation project.

Except for the rare, scholarly restorations of historic interiors, most repainting projects done will employ modern paint formulations. Modern paints can recreate the appearance of historic colors, gloss and texture in varying degrees, but eliminate earlier toxic components such as white lead and volatile organic compounds.

Caution: Paint hazards

Before undertaking any project involving paint removal, applicable state and federal laws on lead paint abatement and disposal must be taken into account and carefully followed. State and Federal requirements may affect options available to owners on both paint removal and repainting. These laws, as well as any requirements prohibiting volatile organic compounds (VOCs), should be requested from the historic preservation officer in each state.

Below is a summary of the health hazards that owners, managers, and workers need to be aware of before removing paint and repainting:

Lead and other heavy metal compounds

In virtually all paints made before 1950, the white or “hiding” pigment was a lead compound, or more rarely, zinc oxide. Work to remove lead paint such as scraping and dry sanding releases the lead–a highly damaging heavy metal–in dust. Lead dust then enters the human system through pores of the skin and through the lungs. The use of heat for stripping also creates toxic lead fumes which can be inhaled.

To mitigate the hazards of lead paint ingestion, inhalation, or contact, it is extremely important to prevent any dust from circulating. Workers should also not eat, drink, or smoke where lead dust is present. Finally, anyone involved in lead paint removal should undergo periodic blood testing. After work, ordinary vacuuming is not enough to remove lead dust; special HEPA vacuums are essential. The surfaces of the room must also be given a final wash with a non-film leaving solution and rinsing well.

OSHA lead regulations and if applicable, EPA Renovation, Repair and Replace guidelines must be followed safeguard associates, other project workers/visitors, customers, the public and environment.

In addition to lead, early oil paints also had cobalt or other heavy metal compounds in them to accelerate drying. A small amount of mercury is also included in some latex paints to help prevent mildew and mold formation.

Volatile organic compounds (VOCs). Organic paint strippers, such as methylene chloride, and oil/alkyd paints have VOCs as their solvent base. Inhaling these fumes can lead to respiratory and other illnesses, and to cancer. Especially in closed spaces (but in the outdoor environment as well) these compounds pollute the air and can damage health.

Taking it further additional reading

Clark, Victor S. History of Manufacturers in the United States Vol. III. New York: McGrawHill, 1929.

Gettens, Rutherford J. and George L. Stout. Painting Materials: A Short Encyclopedia. New York: Dover Publications, 1966.

MacDonald, Marylee. Preservation Briefs 21: Repairing Historic Flat Plaster–Walls and Ceilings. Washington, D.C.: National Park Service, U.S. Department of the Interior, 1989.

Masury, John W. A Popular Treatise on the Art of HousePainting: Plain and Decorative. New York: D. Appleton & Co.,. 1868.

Weeks, Kay D. and David W. Look, AIA. Preservation Briefs 10: Exterior Paint Probl

Reference

PPT American Paint History

PPT American Paint History II

PPT American Paint History III

PPT American Paint History IV

Sources:

The Old House Web

Preservation Brief 28
by Sara B. Chase


Originally published as part of AGC of America’s
Business Development Best Practices Series

Cynthia & Mike are both principals at FMI, the leading management consulting, investment banking

and people development firm dedicated exclusively to the engineering and construction industry.

by Cynthia Paul and Mike Clancy