The Rug Library

The Smithsonian's Museum Conservation Institute suggests neutral-pH, unbuffered acid-free tissue for general textile storage and interleaving.

The Canadian Conservation Institute advises that large textiles such as rugs be stored rolled, with heavy rugs supported on a sealed dowel or metal pipe through a tube so the roll does not rest on its own weight.

Once a textile is rolled for storage, conservators recommend covering it with muslin, cotton sheeting or acid-free tissue and tying it loosely with twill tape rather than tight cords.

Light damage to textiles is cumulative and irreversible: ultraviolet radiation yellows and weakens fibres and fades many dyes.

Light damage depends on total exposure (lux × hours), so 100 lux for 400 hours does roughly the same damage as 50 lux for 800 hours.

Museums commonly light sensitive textiles at no more than about 50 lux and filter out ultraviolet light; even so, the most light-sensitive colours can fade within a few years of continuous display.

The Smithsonian's Museum Conservation Institute suggests textile storage at about 18–20°C with relative humidity below 65%, ideally 50–55%, kept stable because swings make fibres repeatedly swell and shrink.

Mould growth on textiles is encouraged by relative humidity of about 65% or more, warmth and poor air circulation; dehumidifiers and fans help reduce the risk.

Attics, basements and cupboards against exterior walls see large swings in temperature and humidity and are not recommended places to store textiles.

Clothes moth and carpet beetle larvae feed on wool and other keratin-based fibres, and can also attack silk, cotton or synthetics where soiling is present.

Clothes moths lay eggs within a textile's weave; the larvae either tunnel through, making holes, or graze the surface, thinning yarns and weakening the structure.

Museum pest-management guidance notes that holding an infested object at a low enough temperature for long enough will kill common textile pests, which is why controlled freezing is used as a non-chemical treatment.

Conservators advise inspecting woollen items regularly for pests and quarantining newly arrived textiles so insects are not introduced to a collection.

The Institute of Conservation advises that a rug showing signs of pests be wrapped in polythene to isolate it from other textiles and that a conservator be contacted.

The Institute of Conservation notes that light weakens fibres as well as fading dyes, and that silk is the most vulnerable fibre, so rugs are best kept out of direct sunlight.

Textiles absorb moisture from the air: dry heated winter air makes fibres shrink, while damp air makes them swell, stressing old rugs.

The V&A's Ardabil carpet, dated 1539 and made in Iran, is lit only intermittently for a few minutes at a time and displayed behind glass to help preserve its colours.

Hanging a rug on a Velcro support spreads its weight evenly across its width; because Velcro is too stiff to sew directly to a textile, it is attached via a hand-stitched, prewashed cotton sleeve or tape.

The Metropolitan Museum's Department of Textile Conservation cares for a collection of roughly 36,000 textiles, including carpets, tapestries, embroideries and costumes.

Some carpets at the Met are pressure-mounted for vertical display: held against a padded support by light pressure from an acrylic sheet rather than by stitching.

The Canadian Conservation Institute advises that a rug hung for display be stitched to its mount around the edges and with a grid of vertical and horizontal stitching, so its weight is evenly spread.

A common museum policy exhibits textiles at about 50 lux for limited periods, such as three months, then rests them, capping total light exposure over time.

The Victoria and Albert Museum has used low-temperature treatment on large rolled textiles as part of its integrated pest management.