Copyright © 2010, Published by Art of Leadership Enterprises Inc. All Rights Reserved

Care and Preservation of Historic Furniture

by Yuri Yanchyshyn


It could be your grandmother’s china cabinet, a chest brought back by a relative from overseas, a

handmade table purchased directly from the artist or a period chair that is part of a larger collection.

Historic furniture – like the people who created it – comes in a wide range of shapes and sizes. Owning

and living with historic furniture is one of life’s greatest pleasures. On the other hand, it also carries

some tremendous responsibilities, particularly if you want to retain the aesthetic, historical and monetary

value of the objects in your care.


The primary material of most historic furniture is wood. We don’t really think about it, but wood is a

fairly complex organic substance – and different types of wood respond differently to environmental

conditions. Most historic furniture also includes various secondary materials including hardware and a

wide array of surface finishes. 20th century furniture may include non traditional materials, such as

plastics, manufactured woods and tubular metal.


Here are six simple steps you can take to ensure that your historic furniture remains in good condition

for many years to come.


  1. 1.Monitor temperature


Temperature is one of the most critical elements that impacts historic furniture. The optimal

recommended year round temperature range for a general furniture collection is 50-72 degrees. Outside

that range – or even with substantial fluctuations within it – degradation accelerates rapidly. Modern

materials are especially vulnerable. Plastics can warp or become brittle, while metals are susceptible to

delamination, where the coatings are loosened and sometimes begin to flake due to expansion and

contraction. More traditional wooden furniture is not immune, either. Long-term stresses due to change

in temperature can impact glues and varnishes, make coatings opaque and desiccate leathers. Collectors

who are especially concerned about the long term preservation of their collections will keep the

temperature toward the low end of the range.


  1. 2.Keep an eye on humidity


Wood fibers are particularly responsive to changes in humidity, absorbing and releasing moisture. The

optimal recommended relative humidity range is 40-50%. However, in our modern, climate-controlled

environments, interior humidity can vary from over 60% in summer months to under 20% during winter

months. This wide fluctuation places undue stress on historic furniture and can cause warping,

delamination of veneers, gilding and lacquer finishes, splits and loosening of joints. Museums use very

sophisticated control and monitoring systems to avoid damage to their collections. While these are

impractical for most homes and offices, you can purchase relatively inexpensive hygrometers (humidity

gauges) and humidifiers. It is generally not terribly difficult to retain a temperature of 50-72° F and a relative humidity of

40-50%. Above all, avoid subjecting your furniture to wide fluctuations in temperature and humidity.

When moving it from one area to another, make sure the conditions in the new location are as similar as

possible to those in the former one.


  1. 3.Moderate lighting


Light – whether sunlight or artificial light, contains some ultraviolet – which can have a negative impact

on furniture. Usually, it deteriorates the finish layer, but it can often damage the topmost layer of the

wood itself. Upholstery is vulnerable as well. Signs of light damage include bleaching, loss of gloss on

a finish or increased opacity or “cloudiness.” Protecting your furniture from harmful lighting conditions

is straightforward. The first step is to remove historic and valuable furniture from bright rooms. If this

is not practical, keep curtains, shutters or shades drawn during the hours of maximum brightness. You

can also apply some light-intensity reducing film directly to the window glass. If the room happens to

have fluorescent lighting, it is a good idea to place UV-absorbing sleeves over the bulbs. Also, when

furniture is in storage or in seldom-used rooms, cover it with unbleached muslin or a similarly soft,

untreated cloth.


  1. 4.Remove dust and dirt carefully


Just as we don’t think much about wood, we don’t think much about dust; we simply take it for granted

that it’s there. Like wood, though, dust is quite complex. Frequently it contains chemicals and abrasives

that can be damaging to your furniture. Dust should be removed frequently – and with great care.

Establish a regular surface cleaning schedule and use a soft brush and vacuum to remove dust without

abrading the surface.


  1. 5.Be on the lookout for biological predators


Molds, mildews and fungi can be profoundly damaging to furniture and toxic to humans as well. They

typically thrive in moist, warm environments where there is little air movement. Below-ground storage

rooms are notorious for these conditions. Mold and mildew can stain surfaces or etch coatings. In

severe cases, wood rot, a form of fungus, can reduce wood fibers to a powder. Getting the humidity level

under control is the essential first step in addressing fungus or mildew damage. Insects are another

natural predator that can decimate your furniture with surprising speed. Powder post beetles and

furniture beetles are especially common in European furniture. The larvae of these beetles often live

deep in the wood and feed on the wood fibers, emerging only when they become adults,. They can be

especially destructive to furniture’s structural integrity. Be on the lookout for exit holes or frass, the

fine, dust-like product of insect activity. If you discover an infestation, your furniture will need to be

fumigated.


  1. 6.Examine your furniture regularly


It is a good idea to get in the habit of examining your historic furniture on an annual or semi-annual

basis. Get to know its surfaces intimately – even those on the inside or under-side. Examine lacquers

for lifting and cracking that can indicate delamination. Look for flaking on gilded or painted surfaces.

Check thoroughly for cracks in the finish or underlying wood. Scan for changes in the clarity and

transparency of varnishes and shellacs. Study applied carving and inlays to make sure nothing is loose.

Test joints gently to make sure that they are still stable and capable of bearing loads. Study furniture

made of modern materials especially closely for signs of warping in plastics, rust or surface corrosion in

metals and the separation of the layers of plywoods and other manufactured woods.

If your historic furniture is especially valuable – or is part of a collection – it may make sense for you to

enlist the help of a conservator to perform both an initial inspection and periodic surveys. It is generally

much easier – and much less expensive – to correct issues when they are discovered early.



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Yuri Yanchyshyn is the principal and senior conservator of Period Furniture Conservation, LLC, a New

York firm dedicated to the conservation of furniture and objects. More information can be found at

http://periodfurnitureconservation.com


 

detail of a George II chinoiserie table, private collection

detail of a Scott Burton Table, private collection