Damp Proofing – a Home Building Necessity

Moisture can be a threat to your homes, weakening the house and damaging internal wall paints and plaster as well as decorations on them. Seeping moisture into walls can come from various sources. Your home could be situated near a creek, a river, or in a country visited by torrential rains or even occasional flooding and high atmospheric humidity even in the summer months.

These factors attack our homes from outside. But there are many household activities that produce moisture from inside. Cooking evaporates liquids, washing and drying laundry, taking showers – all produce inordinate amounts of moisture, typically about 5 liters a day.

If you have closed or sealed homes with air-conditioning and no open chimneys, the moisture gets trapped inside your home resulting in dampening your home structures, particularly walls. What you need is a good and effective damp proofing for your home.

All building codes in most countries require a damp-proof course or DPC to prevent the capillary action of water seeping through walls from their foundation or getting absorbed from the ground up in a phenomenon called rising damp. A DPC is often employed while in the construction process where a thin strip of plastic or later of bitumen is inserted in between layers of bricks in walls being erected. This is a common process for damp proofing walls that have been used as early as the Romans.

If this was not done while your homes are being built, there are various methods for retroactively damp-proofing your home.

• A common post-construction method use is to drill holes in the masonry works in walls at regular distance intervals into which is injected with damp proofing products made of silicone or other penetrating chemicals like damp-proofing creams that get absorbed into the masonry and acts as a waterproofing barrier when dried. Another way would be to drill holes and inject larger amounts of the chemical in cement joints. A damp proof membrane or DPM perform the same function for solid floors.
• Using dehumidifiers have been known to reduce moisture content but they are limited to control moisture inside the house, not from outside. Apart from being expensive, dehumidifiers required regular maintenance to empty the collected water as they can be noisy to operate.
• Using special anti-damp or mould paints work but only as a temporary solution. The paints use biocide which contains toxic chemicals so that mould growth is controlled but the moisture problem can re-appear over time once the chemicals have lost their efficacy. This may happen within a few months or years depending on the strength and type of chemical used.