According to Marie Bruno, painting conservator and research director at Lowy, “A painting needs to be lined when the original canvas can no longer provide adequate support for the ground and paint layer.” Canvases made before the turn of the century were always woven from organic materials — such as linen or cotton — that naturally deteriorate and weaken over time. Yet even newer canvases, many of which were machine-made and pre-primed, may need to be lined because of extensive damage to the paint layer or an injury to the textile itself. “As conservators, our mandate is to stabilize and insure the future safety of the artwork, and use the least invasive techniques possible to accomplish this,” explains Larry Shar. “We look at localized methods first.” Sometimes a work, especially one that has cracking or cupping of the paint layer, can be restored sufficiently using humidity treatments. Spot bonding, mending or patching can treat punctures and small tears.
“Often these remedies are used in conjunction with a humidity treatment,” Bruno adds. Shar notes that the environment in which the painting will hang is also considered. “A work that will be displayed in a museum or a tightly controlled environment, with expert handlers and constant humidity levels could be left in a less protected state than one in a private home, where smog, dust and temperature changes are virtually unavoidable and where it is not under the scrutiny of an expert.” When a painting cannot be sufficiently consolidated using a localized remedy or by infusing the entire artwork, if the hole or tear is so large that the edges of the patch will eventually show on the surface, or if a distortion such as cupping is so severe that it interferes with the aesthetics of the work, a new lining may be called for.
But what exactly does it mean to “line” a painting? According to Bruno, “a new canvas, usually made of 100% Belgian linen, is applied to the verso of the work for additional support.” Lining techniques used today involve minimally invasive methodology and materials. Thermoplastic adhesives such as BEVA can require less heat and pressure than wax or aqueous glue linings. Interlayer materials such as mylar or PeCap also ensure against weave interference often seen in more aggressive linings where original canvases are fused directly to another linen support. Our knowledge of and experience in the use of these new materials and techniques provide us with safer, less invasive , more reversible linings than ever before.