Caring for Paintings
Paintings are perhaps the most common type of artwork and in addition to their obvious
aesthetic value many are culturally significant because of historical or sentimental
value. No matter what the importance, any given piece of artwork may require painting restoration
and/or conservation treatment.
Paintings are made up of several layers, from the support onto which the ground
is applied to the paint that covers the ground and creates the image. The support
can be made of nearly any material but is typically cotton canvas, linen, wood,
masonite or plaster. The support is often, but not always, primed with either an
acrylic gesso or rabbit skin glue and a solid layer of paint. The paint itself is
often chemically complex, containing synthetic or earth pigments suspended in oil,
acrylic, tempera, wax or other mediums. These elements are normally very stable,
but exposure to environmental changes or improper storage conditions can result
in cracking, blistering or discoloration.
One of the most common causes of discoloration on paintings is yellowing varnish.
As a general rule, varnish is meant to protect the paint surface by covering it
and catching any airborne grime. Discolored varnish can be professionally removed
with gentle solvents without harming the paint layer. In certain situations, when
varnish is applied before oil paints have dried extra care must be taken to ensure
that the paint is not removed along with the varnish. Structural damage such as
cracking, flaking or fungi growth can also be treated by a painting restoration specialist.
ENVIRONMENT FOR PAINTINGS
Where a painting is stored or displayed, and even how it is hung on the wall, can
greatly affect its longevity. Depending on the type of paint used, humidity may
cause cracking or peeling. Ideally a painting should be stored in an environment
that is comfortable for people, around 70 degrees Fahrenheit, and with a relative
humidity between 40 and 60 percent. Drastic changes should be avoided as well.
A simple backing board attached to the wooden stretchers helps to keep dust and
debris off of the normally raw reverse side of the canvas and can protect the object
during handling. This backing should be sealed with no space for air to enter. All
paintings should be hung by picture wire strong enough to support the weight of
painting and frame. The wire should be stretched fairly taught from one side to
the other. We recommend using a hanger attached to the frame with two separate screws.
Do not use eye screws as these can pull out. Paintings should always be hung by
picture hooks appropriate for the weight of the piece – never on nails. If hung
on an exterior wall it is recommended that small rubber bumpers be placed on the
back of the painting to allow air to circulate behind it. A thin insulating board
may also be used to isolate the back of the painting from an exterior wall.
Paintings should not be displayed over a working fireplace as this will expose them
to heat and soot, causing significant damage in a short period of time. Although
a fireplace is often a focal spot for a room, a painting displayed above a mantel
will be exposed to soot, heat and environmental extremes. Hanging paintings above
heating and air conditioning vents or in bathrooms with tubs or showers is also
inadvisable because the rapid environmental fluctuations will be harmful. Select
a safe place away from high traffic and seating areas.
Paintings should never be in direct sunlight which can cause faded colors and other
types of damage. Halogen lights are a poor choice since they emit damaging ultraviolet
light. Lights that attach to the top of the paintings are also not recommended.
If these should ever become loose and fall they may scratch or rip the canvas. Recessed
ceiling lights, track lighting and color-balanced incandescent or tungsten bulbs
are the best choices.
FRAMING OF YOUR PAINTINGS
Ideally a painting should be held in the frame with metal offset clips that are
attached to the frame with screws. Brass mending plates can be bent and adjusted
so there is light pressure on the back of the stretcher or strainer. Sometimes nails
are used to frame paintings, but nails can rust, fall out, or protrude through the
canvas. Ask the framer or conservator to pad the rabbet (the part of the frame that
touches the face of the painting) with felt or another suitable material to protect
Paintings should never be stored in damp areas such as basements, nor should they
be left in attics where temperatures can greatly fluctuate. Ideally paintings should
be hung on a wall even when in storage, but they may be stored vertically with stiff
boards protecting the front and back of each painting.
Paintings should be moved as little as possible. Whenever paintings are handled
they are at increased risk of damage. If you must move a painting, be sure that
your path from location to location is clear so that you do not have to maneuver
around furniture or obstacles. For larger works lift with one hand on the bottom
and one on the side to keep the piece steady. Smaller works may be carried by holding
each side. Unless a painting has flaking paint it should be carried vertically just
as it was hanging on the wall. Any wires that may be loose and hit the back of the
painting should be secured and all hardware should be inspected before the painting
is re-hung. Care should be taken so the painting does not rest on the stretchers
as this can leave marks and indentations.
Do not lift the painting using the top of the frame or stretcher as these areas
can break under the weight of the whole painting. If the painting is too large for
one person to lift properly, have a second person help lift and carry it. If the
painting is to be set on the floor or leaned against a wall it should be slightly
elevated on small padded blocks.
Paintings should be inspected every six months in order to identify any problems
before they become too severe. Paintings may be lightly dusted with a sable brush
(never a feather duster) and only after checking for any loose, flaking paint. Do
not use solvents or liquids of any kind on the painting. Aerosol sprays such as
air fresheners, window cleaner, furniture polish and foggers should never be used
around paintings. It is also important to remove paintings from the room when painting,
plastering or steam cleaning carpets.
If a painting is in an area that has been flooded or fire-damaged it must be removed
and taken to a conservator or painting restoration specialist. If there is any sign of flaking
paint lay the painting flat with the image facing up. Do not wipe smoke, soot or
debris from the surface as this may loosen paint and cause severe damage.
Insect infestation, flaking paint, paint loss, torn canvas, cracks with lifting
edges, wrinkles or draws in the canvas, mold growth, grime or discolored varnish
are all problems that only a professional conservator is trained to address.