Outdoor Collections

What are the most common types and causes of damage?

Objects in an outdoor setting are fully exposed to almost all of the factors that cause damage and deterioration.

Being outside, sculptures, memorials and other objects are very vulnerable to physical damage such as:

• scratching and abrasion, for example, through children climbing on objects;

• graffiti;

• deliberate breakages and other forms of vandalism;

• accidental damage such as vehicles crashing into—or trees falling on—objects;

• splitting and cracking through plants growing in small fissures in the objects; and

• splitting, cracking, distortion, and loss of coatings and paint layers as objects adjust to extremes and fluctuations in their environment. This type of damage rarely happens quickly. It usually happens over a long period and is often considered to be natural weathering.

This imitation stone work has split, leaving it vunerable to further damage. Photograph courtesy of Artlab Australia, reproduced with permission of Carrick Hill

Environmental factors which can contribute to physical damage include:

• extremes and fluctuations in temperature and relative humidity;

• dust storms and dirt picked up by cars on dirt roads—high velocity dust particles act like a sand-blaster. Stone surfaces—especially the softer stones such as limestone and sandstone—are particularly vulnerable to this type of damage especially on areas with fine-detailed carving;

• chipping and flaking of the surface of objects caused by mowing or whipper snippering too close to them; and

• damage from insect and mould attack.

Chemical deterioration also happens. Light, UV radiation, high humidity and high temperatures all contribute to chemical changes, which can include:

• corrosion;

• fading;

• discolouration; and

• materials drying out and becoming brittle.

Airborne pollutants, which produce acid rain, are one of the major causes of damage to outdoor objects. The unsightly black and brownish-yellow streaks seen on many bronze sculptures are a direct result of pollution. This is not just a problem in the city or in industrial areas. Acidrain can travel vast distances before actually falling. Pollution from fertilisers and crop sprays can also have a detrimental affect on objects in outdoor settings.

Salts cause damage to metals, as well as to concrete and stone.

This bronze sculpture is vulnerable to plant growth below the water level and to accelerated corrosion at the water surface. If the water contained chlorine, extensive damage would occur. Photograph courtesy of Artlab Australia, reproduced with permission of Carrick Hill

As bird droppings age, they can become quite acidic and can etch into the surface of outdoor objects.

Mould growth also involves chemical action on the object, as moulds digest the items they are feeding on. Moulds can also stain the surfaces on which they are growing.

Plants growing on objects can cause chemical damage, especially if they are feeding off the object.

Resins and other substances which fall on objects from trees can be very difficult to remove from porous materials, and can stain and disfigure the objects.

This piece is made from wood and iron. It is vulnerable to corrosion of the iron and to deterioration of the wood. It also collects large amounts of pine needles from surrounding trees, because of its shape. Photograph courtesy of Artlab Australia, reproduced with permission of Carrick Hill.