What is damp proofing explain the causes of dampness?

Subsoil moisture rising through foundation beds. Rainwater seeping in from external walls. Rainwater coming through parapet and compound walls. Moisture deposited on building due to condensation.

What are the sources and effect of dampness?

Top of walls: Parapet and compound walls also become a source of dampness as the rain water descends down the wall and causes dampness. Condensation: When warm humid air is cooled, condensation takes place. Due to condensation, moisture is deposited on the walls, floors and ceilings and causes dampness.

What is damp proofing in construction?

Dampproofing is intended to keep out soil moisture while waterproofing keeps out both moisture and liquid water. Dampproofing is a coating, usually asphalt-based, that is either sprayed on or hand applied to the outside of the wall.

How do you find the source of dampness?

Dry the wall surface with a fan heater, then tape some kitchen foil tightly over the damp area. If the surface of the foil is wet after 24 hours, you have condensation. If the foil is dry but the wall surface beneath it is damp, you have rising or penetrating damp.

Which is the main source causing dampness in badly designed kitchens?

Explanation: The process of condensation takes place when the warm humid air is cooled. This is due to the fact that cool air can contain less invisible water vapours than warm air. The moisture is a deposit on the walls, floor and ceiling. This is the main source causing dampness in badly design kitchens.

Why is damp proofing important in structures?

Damp proofing ensures that your walls resist this moisture hazard so that your family can stay safe and healthy, breathing freely. When condensation builds up inside your walls, or water is allowed to sit without sufficient ventilation, mildew and bacteria begin to grow. Damp proofing can help eliminate this problem.

What is damp proofing walls?

Damp proofing is the term used to describe a method of treating rising damp in walls as opposed to humidity control, which combats condensation, or waterproofing, which safeguards against penetrating dampness and water infiltration via other sources.

How many types of damp proofing are there in construction?

Types of Materials for Damp Proof Course Flexible Materials: Materials like bitumen felts (which may be hessian based or fiber/glass fiber-based), plastic sheeting (polythene sheets), etc. Semi-rigid Materials: Materials like mastic, asphalt, or a combination of materials or layers.

What is damp proof membrane?

A damp-proof membrane is a moisture-inhibiting foil that is 100\% watertight (unlike a breather membrane!). Thus damp – which exists in the surrounding air in the form of condensation – is prevented from penetrating the membrane.

Why does dampness occur in walls?

Condensation damp is caused by moist air condensing on walls. Warm & moist air comes into contact with a cold surface such as the walls, and the air can’t hold the moisture, causing drops of water to appear and causing mold on your walls.

What is flexible material which is commonly used for the damp proofing?

Materials widely used for damp proofing include: Flexible materials like butyl rubber, hot bitumen (asphalt), plastic sheets, bituminous felts, sheets of lead, copper, etc.

Which of the following is a miscellaneous causes of dampness?

Miscellaneous sources or causes like poor drainage of a building site, the imperfect orientation of a building, defective construction, etc. The splashing of water on wall surfaces. Leakage of the site which may result in waterlogging, and ultimately, it may result in dampness in a building.

What is DPC in construction?

A damp-proof course (DPC) is a horizontal barrier in a wall designed to resist moisture rising through the structure by capillary action – a phenomenon known as rising damp. DPC is used to stop dampness in buildings. In theory, due to capillary movement of water, water rises from the earth to the building.

How to damp proof Foundation?

The first step of the process involves clearing the area around the foundation.

What is a damp proof course?

• DAMP-PROOF COURSE (noun) The noun DAMP-PROOF COURSE has 1 sense: 1. a course of some impermeable material laid in the foundation walls of building near the ground to prevent dampness from rising into the building. Familiarity information: DAMP-PROOF COURSE used as a noun is very rare.