Encaustic painting is one of the oldest and longest lasting forms of art there is. There are numerous examples of ancient Egyptian encaustic paintings which remain beautiful after nearly 2000 years. Thus when properly cared for, we can preserve and enjoy these incredible paintings for generations.
How does one properly maintain and care for encaustic art? Well, there are a few basic considerations. Since encaustic paintings are made primarily from wax, extreme temperatures are the primary enemy. Freezing temperatures can cause the wax to become brittle and easily shattered if dropped. Whereas high temperatures can cause the wax to become soft and even melt. Both of these results would be a tragic end to a treasured work of art, so its best to keep paintings in a climate controlled space.
When does the wax begin to get too hot? This depends on a number of factors. Encaustic work is traditionally made using beeswax, damar resin and some form of pigment. The proportions of these three elements will affect the melting temperature of the finished work. Damar resin serves to cure and harden the painting over time making it less susceptible to melting and other damage. However, other additives can lower that melting point. Some artists choose to use oil paint to pigment their wax, or use other varieties of wax for varying effects.
Due to the fact that we can't know what proportions of waxes, resins and oils were incorporated into the painting, we can never be sure the exact temperatures at which a painting will become vulnerable. However, we can follow some basic guidelines. Keep the painting away from heat sources for obvious reasons. Also keep paintings out of direct sunlight which may heat them up. (Never place any art in direct sunlight, sun fades even the most resilient of colors.) Furthermore, it's best not to put them in a frame with glass, as the glass will magnify light and trap heat. Generally speaking, temperatures over 120°F could cause the painting to shift and eventually melt or slide off their painting surface. So it's best to keep paintings well below this temperature. Basically, if its comfortable for you, it will be safe for the painting.
How about cleaning? With no glass covering the piece, they can pick up dust and dirt. Encaustic paintings can be gently wiped down with a soft, damp, lint-free cloth. Thanks to the damar resin they are naturally varnished from within the painting and require no varnish or glass to stay protected. However, from time to time the surface of an encaustic painting can get hazy. The older a painting is, the less likely this is to happen thanks to the damar resin curing process. However, the surface can be gently buffed with a soft, lint-free cloth when the painting is at room temperature or cooler.
If the painting needs to be moved, try and package it such that nothing touches the surface or use wax paper or silicon paper to protect the surface. Even under stable temperatures a fingernail can press into the wax and mar the surface. Bubble wrap and cardboard can be used to cushion the painting before boxing the piece. Furthermore, its important to try and insulate the painting against temperatures under 40°F and above 80°F.
While encaustic paintings do require some special care, they are one of the most beautiful and enduring art forms in the world. A properly maintained encaustic painting is something which could be passed down over generations as a family heirloom and be enjoyed for multiple lifetimes. The Egyptian Fayum mummy portraits stand in testament to the resilience of encaustics and serve as a valuable bridge into the past. With luck and care, your paintings may some day do the same.