Although furniture can be made of a wide variety of materials – plastics, textiles, leather and plant-based materials, glass, metals, and more – this blog post focuses primarily on wooden furniture. Please check out our other Caring for Family Treasures posts on these other materials for information about how to care for your non-wooden furniture.
Wood used to make furniture comes from trees or other woody plants like bamboo. The trees can either be hardwoods, such as cherry, walnut, mahogany, and maple, or softwoods, like pine, cedar, and fir. The endless possible ways to process woods include: riven into boards, turned on a lathe, or sawn millimeters-thin and glued onto other substrates as veneer. Wood is an organic material, meaning that it can shrink or expand in response to environmental changes; it will fade upon exposure to light, and it is a favorite snack for some wood-loving pests.
We all know what it’s like to have a sticky dresser drawer or a cabinet door that won’t stay closed. This happens when relative humidity is too high (wood cells swell as they absorb the excess moisture) or too low (wood cells shrink as they release moisture). In extreme environments, such as minimally climate-controlled attics and basements, wood can warp or split. Veneers will often become detached or bubble or tent upwards. In many cases, once this happens the damage is irreversible. High humidity environments, in addition to swelling wood, can also promote mold growth and insect activity. Keeping your prized furniture in rooms with moderate temperature (~70ºF) and humidity (~50% RH) is ideal, but this may be unattainable or unsustainable. If so, it is important to aim for an environment with fewer extreme swings in temperature and humidity. If you have a room that you know becomes particularly dry in winter or damp in summer, investing in some inexpensive equipment can go a long way toward minimizing the effects of seasonal swings. A humidifier will help wood regain moisture content during dry winter months, and a dehumidifier or some silica gel packets inside drawers or other enclosed spaces will help wood from taking on too much moisture in summer.