Preserving Art at Home: Light, Humidity and Handling

Art preservation for private collections starts with prevention

Art preservation for private collections is mostly a matter of preventing slow damage rather than repairing sudden damage. Conservators describe the main risks as agents of deterioration, among them light, incorrect humidity and temperature, pests, pollutants, physical force, water, fire and theft. In a home, the first few are constant and the rest occasional, which is why everyday conditions deserve the most attention.

Preventive care has a practical advantage. Treatment is costly, can take a work out of the house for long periods, and always alters the object to some degree. Keeping a work in conditions that slow its deterioration avoids much of that, and most of the measures involved are simple once the risks are understood.

The guidance here is deliberately general. Different materials tolerate different conditions, and the right targets for a particular object should come from a conservator who has seen it.

Controlling light

Light damage is cumulative and cannot be reversed. Every hour of exposure contributes, and the effects, such as fading colours, yellowing paper and weakened fibres, build up over years before they become obvious. Ultraviolet radiation is the most damaging part of the spectrum, but visible light causes damage too, so filtering UV reduces the risk without removing it.

Sensitivity varies. Works on paper, watercolours, textiles, photographs and some dyes and pigments are highly sensitive. Oil paintings, stone and metal are generally less so, although varnishes and some paint layers still change with light. NEDCC's guidance on protection from light is a useful introduction to the principles, and a conservator can advise on suitable levels and display periods for specific works.

Practical measures include hanging sensitive works away from direct sunlight, using UV-filtering film on windows or UV-filtering glazing in frames, closing blinds in rooms that are not in use, choosing lighting that emits little or no UV, and rotating the most sensitive works so that each spends time resting in storage. Picture lights fixed to frames can concentrate light and heat on one part of a work and are worth discussing with a conservator before use.

Keeping humidity and temperature stable

Many artworks are made of materials that absorb and release moisture. Canvas, wood, paper and some adhesives swell and shrink as relative humidity changes, and repeated movement contributes to cracking, flaking, warping and cockling. High humidity also encourages mould and insects, while very dry conditions can make some materials brittle.

For most collections at home, stability matters as much as any particular reading. The places to avoid are predictable: above radiators and fireplaces, near heating and cooling vents, on exterior walls prone to condensation, in bathrooms and kitchens, and in basements and attics where conditions swing widely. Moving a work to an interior wall in the same room can make a real difference.

A simple data logger or hygrometer placed near important works will show how conditions in each room actually behave across the seasons. Those readings are useful when asking a conservator what range suits a particular object, and whether additional control, such as a humidifier, a dehumidifier or a sealed frame, is justified.

Seasonal transitions are when conditions tend to change fastest, particularly when heating is switched on or off. Changes made gradually are gentler on most objects than sudden ones, which is worth remembering when a house has been closed up and is reopened.

Handling art safely

More damage happens during handling than most owners expect, usually while works are being moved, rehung or cleaned around. The principles are simple and apply to almost every type of work, from a small drawing to a large canvas.

Before a work is moved, check that the frame is sound, the work is secure within it and any glazing is intact. A work with flaking paint or a loose frame should stay where it is until a conservator has seen it, since movement is what turns a small problem into a loss.

Cleaning, pests and routine checks

Cleaning is where well-intentioned owners most often cause harm. Painted surfaces should not be wiped, dusted with cloths or treated with any household product, and even gentle cleaning of a paint surface is a job for a conservator. Frames and glazing can be dusted with care; for glass, cleaner should be sprayed onto the cloth rather than onto the glazing so that liquid cannot run behind the frame. Acrylic glazing needs a cleaner made for it.

Pests are a quiet risk. Insects can attack wooden frames, stretchers, paper, textiles and some adhesives. Signs include small holes, fine powder, droppings or shed casings near or behind works. Any evidence of pests or mould should be reported to a conservator rather than treated with household sprays.

Dust and airborne pollutants settle on surfaces over time. Glazing, backing boards and dust covers on frames provide a simple barrier, and building work in the house, such as sanding, plastering or painting, is a reason to move or wrap works in advance.

A regular walk-round, perhaps each season, is the simplest preventive tool. Looking at each work in good light, including the reverse where practical, and comparing it with the images in its condition file will catch new cracks, lifting paint, stains or loose fixings while they are still minor.