Protect and Maintain Wood Furniture

Several of the issues discussed below can and should be addressed in the design and construction of wood furniture. To mitigate their effects, Stephan Woodworking incorporates Best Traditional Woodworking Practices.

An all-around article, from the Smithsonian Institute's Museum Conservation Institution, is Furniture Care and Handling. For anyone interested, the following link is the home page for the Smithsonian's Museum Conservation Institution.

Relative Humidity

Light

Everyday Use

Regular Cleaning and Polishing

Stains, Rings, Spots, Scratches

Sticking Doors and Drawers

Storage

Return to Woodworking Information page

RELATIVE HUMIDITY

Several sources addressing antique furniture in the home recommended an average indoor temperature of 70 degrees F and an average indoor relative humidity of 30-50%. Gauges to measure relative humidity can be found by searching for "humidity gauge" or "hygrometer."

One state natural gas trade association web site suggested that people feel more comfortable when relative humidity is in the range of 20-60%. During the winter when the outside temperature is at or above 20 degrees F, that same web site suggested an indoor relative humidity range of 35-40%. A (different) state university agricultural education web site suggested for colder climates an indoor relative humidity range of 30-40% in the winter. Many heating systems incorporate an automatic humidifier to add moisture to indoor winter air.

That state university agricultural education web site suggested (again for for colder climates an indoor relative humidity in the summer below 65% to minimize the potential for mold growth, and below 50% to minimize the potential for dust mites. A competent heating and air conditioning contractor should be consulted to help identify ideal seasonal indoor relative humidity levels and develop a system to achieve and maintain desirable those levels.

Moisture can condense on the inside surface of single pane windows when the outdoor temperature drops, and in extreme situations can condense on the inside surface of walls. The condensation occurs because the temperature of that inside surface is below the dew point of the air in the house. The solution is to increase indoor air circulation on that surface and/or lower the indoor relative humidity. (This explains why the recommended indoor relative humidity level is lower in the winter than in the summer.)

On the other hand, an indoor relative humidity that is too low can cause itching, dry skin, excessive static electricity, dry mucous membranes and increased susceptibility to colds and respiratory infections. When indoor relative humidity is too low, moisture on the skin evaporates more quickly, making one feel chilled even at higher thermostat settings. The solution to this problem is to increase the indoor relative humidity.

Gauges to measure relative humidity can be found by searching for "humidity gauge" or "hygrometer." These gauges are not always especially accurate. One method was found that allows testing the accuracy. It suggests sealing a gauge in a plastic bag along with a cup containing one-half cup of water and one-quarter cup of table salt. After at least 12 hours at room temperature, it said the meter should read 75 percent relative humidity.

An excellent in-depth resource for those interested in learning more about the impact of relative humidity on furniture, and equally important, changing relative humidity, is Understanding Wood: A Craftsman's Guide To Wood Technology by R. Bruce Hoadley.

The Smithsonian Institute's Museum Conservation Institution has an article titled Furniture Care and Handling which discusses relative humidity on pages 3-4.

An article from Uniclectica Antiques and Collectibles (?) titled Preventing Warping and Splitting of Hollow Wooden Furniture suggests keeping stored furniture (dressers, armoires, presses, and such) filled with loose uncolored terry-cloth cotton towels to buffer relative humidity swings. The same concept could be applied to empty furniture not in storage.

Artifact Care Series #2: Caring for Your Furniture is an article from the Museum of Florida History.

Return to Top of Page

LIGHT

The Smithsonian Institute's Museum Conservation Institution article titled Furniture Care and Handling addresses the effect of light on page 3.

Artifact Care Series #2: Caring for Your Furniture is an article from the Museum of Florida History.

Return to Top of Page

Everyday Use

The Smithsonian Institute's Museum Conservation Institution article titled Furniture Care and Handling discusses everyday use and handling on pages 5-8.

Return to Top of Page

REGULAR CLEANING AND POLISHING

Dust particles and dusting tools can be abrasive. Clean dry soft cloths lightly dampened with a few drops of water can be used to remove surface dust. Wipe slowly near edges - loose threads can catch wood slivers and break them loose.

Felt pads under lamps, bowls, trivets, and such can prevent a hard edge from scratching a finish, but those pads over time can accumulate abrasive dust particles. When moving lamps, bowls and other objects, always lift rather than slide.

Coasters can always be used under drink glasses and plants. Those with rims offer more protection. Mats and other plastic items can emit fumes that will damage finishes over time.

Keep wood from getting wet or soaked. A slightly damp cloth is preferrable to a wet one. Wipe up spills promptly and allow the surface to dry thoroughly before returning lamps, bowls, and other items.

Avoid use of strong solvents near furniture. This includes perfume, strong drinks, and other examples of concentrated alcohol; nail polish remover and acetone; and harsh cleaners.

The Smithsonian Institute's Museum Conservation Institution article titled Furniture Care and Handling discusses maintenance and cleaning in detail on pages 8-13.

Artifact Care Series #2: Caring for Your Furniture is an article from the Museum of Florida History.

Return to Top of Page

STAINS, RINGS, SPOTS, SCRATCHES

There are any number of home remedies for removing stains, rings and spots in finish. Many if not all can damage the finish further if not used correctly and with caution. In general, treatment might be left to a furniture refinishing expert. Many such treatments are mild abrasives which if used in excess can change the sheen and possibly rub off a layer of finish. Some suggest the use of heat, which can severely damage the finish.

There are a number of common finishes, and determining the particular finish used is often a trial and error approach.

Scratches are common, but can be made less noticeable by adding some color without trying to fill the depth of the scratch. Shoe polish is commonly mentioned in how-to articles; tinted furniture wax and furniture touchup (wax) colorsticks are often found in hardware and woodworking stores. Some furniture waxes have been found to contain harsh solvents that can damage furniture finishes, and shoe polish and furniture waxes may contain silicone. Silicone oil is a persistent contaminant that one might wish to avoid introducing to fine furniture.

Return to Top of Page

STICKING DOORS AND DRAWERS

Typically, doors and drawers that stick or bind only occasionally are a result of a temporary increase in the moisture content of the wood. This moisture content rises when the relative humidity in the immediate environment increases. The relative humidity in homes and offices often rises in the summer during periods of air conditioning use, then drops as fall and winter approaches.

The safest response to a binding or sticking door or drawer is to wait for the average relative humidity to decrease, and within a few weeks the wood should contract so that the door or drawer operates freely. At that time, one can consult a heating and air conditioning contractor to discuss whether relative humidity controls for the home or building might be appropriate. Doing so may eliminate the problem, and create a more healthy living environment as well.

Alternatively, one can contact a furniture conservator regarding the door or drawer. Home remedies likely won't correct the underlying cause of the problem, and may harm the furniture.

Return to Top of Page

STORAGE

An article from Uniclectica Antiques and Collectibles (?) titled Preventing Warping and Splitting of Hollow Wooden Furniture suggests keeping stored furniture (dressers, armoires, presses, and such) filled with loose uncolored terry-cloth cotton towels to buffer relative humidity swings. The same concept could be applied to empty furniture not in storage.

Return to Top of Page

Return to Woodworking Information page

Appointments are suggested for your convenience.

don.stephan@stephanwoodworking.com