PREFERENCE IN ASSESSMENT OF BASEMENT MATERIAL FOR DAMP PROOFING

Damp proofing is a material that resists the passage of water with no hydro-static pressure and waterproof as a treatment that resists the passage of water under pressure. Damp proofing in construction is a type of moisture control applied to building walls and floors to prevent moisture from passing into the interior spaces. Damp problems are one of the most frequent problems encountered in homes.Dampproofing is a coating, usually asphalt-based, that is either sprayed on or hand applied to the outside of the wall. Though less frequently recommended in modern residential construction, it is still an acceptable form of treatment in many situations. The drawbacks include an inability to seal larger cracks or holes left by form ties and the potential for damage by coarse or careless backfill. But with proper surface drainage, correctly installed foundation drains at the footing, and the absence of hydrostatic pressure to drive water infiltration, dampproofing can supply adequate and long-lasting protection for many crawl spaces and basements.

There is a distinct difference between dampproofing and waterproofing. Dampproofing is intended to keep out soil moisture while waterproofing keeps out both moisture and liquid water. Buildings have been damp proofed for years, a practice that used to be mistakenly referred to as waterproofing.Waterproofing a foundation requires the same care as damp proofing in regard to surface treatment and drain pipe, but is much more exacting in the treatment of the wall itself. Obviously, if there is any doubt about whether or not dampproofing will do the job, it's best to spend the extra time and money to waterproof, particularly for habitable space.

Local conditions vary widely and help determine the right choice for preventing water infiltration. Some areas with drier climates and lower water tables regularly build basements with foundation walls that may be 10 feet tall. Other areas, with high annual rainfall, high water tables, and no frost in the soil, more commonly use slab-on-grade foundations. But even these foundations need protection to keep moisture from migrating up from the ground through the slab.

Materials widely used for damp proofing include:

·         Flexible materials like butyl rubber , hot bitumen, plastic sheets, bituminous felts, sheets of lead, copper, etc.

·         Semi-rigid materials like mastic asphalt

·         Rigid materials like impervious bricks, stones, slates, cement mortar or cement concrete painted with bitumen, etc.

·         Stones

·         Mortar with waterproofing compounds

·         Coarse sand layers under floors

·         Continuous plastic sheets under floors

Damp proofing is accomplished several ways including:

A damp-proof course(DPC): this is a barrier through the structure by capillary action such as through a phenomenon known as rising damp. Rising damp is the effect of water rising from the ground into your property. The damp proof course may be horizontal or vertical. A DPC layer is usually laid below all masonry walls, regardless if the wall is a load bearing wall or a partition wall.

A damp-proof membrane (DPM) is a membrane material applied to prevent moisture transmission. A common example is polyethylene sheeting laid under a concrete slab to prevent the concrete from gaining moisture through capillary action. A DPM may be used for the DPC.

Integral damp proofing in concrete involves adding materials to the concrete mix to make the concrete itself impermeable.

James K Brouk here is seen explaining some long term benefits of Basement wall water Proofing and why it is important to hire the services of best of professionals for any kind of Damp proofing.