With heavy rains in most parts of the country, it might be a good idea to take a look at your art collections, whether big or small. High humidity combined with warm temperatures can cause several issues in most artworks, especially if these are housed in non-climate-controlled environments. The problems and the extent of damage can vary depending on the material and the medium of the artwork, and the amount of exposure to the changed weather conditions.
In general, weather variations are fairly extreme in most parts of the country. From blistering summers to heavy rains and then cold temperatures, the degree of change in environmental temperature and moisture levels itself is enough to cause materials to crack, flake, warp, rust and encourage mould to grow. These are just some of the issues that can make an appearance suddenly unless monitored closely.
Many homes are air-conditioned, but the air conditioning units may not be switched on at all hours, which makes artworks more susceptible to fluctuating environmental conditions. In general, a high relative humidity tends to encourage the growth of mould and may cause materials such as paper, fabric and canvas to absorb moisture and expand. These will then contract when the air becomes dry and this repeated process of expansion and contraction eventually affects the surface of the artwork. Layers of pigment get impacted too and may begin to flake, crack and separate from the substrate.
If there is a coat of varnish over a painting, it may begin to crack, or mould spots may begin to appear under its surface, especially when the varnish layer has been applied over paint that is not completely dry. You may also notice discolouration or spots of cloudiness on the surface when the varnish or the paints undergo a chemical reaction due to high humidity.
Similarly, due to high humidity, wood, including wooden frames, can expand, bend, or show some signs of distortion, and may develop cracks over time. Metallic materials tend to get corroded, rusted or tarnished when moisture levels are high. A layer of protective sealant or weatherproof coating on certain surfaces can be very useful and can substantially delay the ageing and decay process.
Preventive care and regular examination of the art by a professional conservator can be helpful. In the meantime, it might be advisable to ensure that environmental variations are avoided as much as possible; a dehumidifier during the rains and a humidifier during dry weather can be installed based on the location of the artworks.
The author is a Bengaluru-based art consultant, curator and writer. She blogs at Art Scene India and can be reached on artsceneinfo@gmail.com
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