Moisture is the silent enemy of brickwork. Rising damp, rain penetration, and groundwater seepage cause efflorescence, plaster peeling, structural weakening, and unhealthy interiors. Prevention starts at construction — retrofitting is expensive and rarely as effective.
What is DPC (Damp Proof Course)?
A DPC is a horizontal barrier installed within the wall at plinth level (typically 150–300mm above ground level) that prevents moisture from rising through the brickwork by capillary action.
Common DPC Methods
| Method | Material | Best For |
|---|---|---|
| Cement concrete DPC | 1:1.5:3 concrete, 40mm thick | Most residential construction |
| Bitumen felt DPC | IS 1322 bitumen felt sheet | Areas with high water table |
| Polymer sheet DPC | HDPE / polythene sheet (400 gauge) | Cost-effective option |
| Mortar DPC | 1:3 cement mortar + waterproofing compound | Partition and compound walls |
How to Install a Cement Concrete DPC
- Complete brickwork up to plinth level (typically 2–3 courses above ground)
- Level the top surface of the last brick course
- Apply a 40mm thick layer of 1:1.5:3 cement concrete across the full wall width
- Add waterproofing compound (Pidilite / Dr. Fixit at recommended dosage) to the concrete mix
- Allow 24 hours curing before continuing brickwork above DPC level
- The DPC layer must extend beyond the wall face by at least 25mm and slope outward
External Wall Waterproofing
For external walls exposed to monsoon rain, additional protection includes:
- External plaster: 1:4 cement-sand plaster with waterproofing compound, minimum 15mm thick
- Water-repellent coating: Silicone-based water repellent applied after plaster curing
- Weep holes: Small drainage openings at the base of retaining walls to relieve hydrostatic pressure
Why Brick Quality Matters for Damp Prevention
Bricks with water absorption above 20% (common in underfired Bull's Trench kiln bricks) act as sponges — they absorb and transmit moisture even through DPC barriers. BBC1 Zigzag kiln bricks consistently measure 12–16% water absorption, providing inherent resistance to moisture penetration.
For waterproofing guidance specific to your project, contact BBC1 at +91 97280 65410.