A damp course is a continuous physical barrier installed horizontally through a brick or block wall just above ground level. It stops groundwater from wicking upward into the masonry and interior framing through capillary action. Current construction uses thick polyethylene plastic or polymer-modified bitumen, while older buildings often relied on slate, lead, or dense engineering bricks.
Heard on the job
Make sure you lap the damp course at least six inches at the corners before laying the next block.
Insider tip
Bridging the damp course with exterior soil or rendering is a common rookie mistake that completely defeats the barrier and guarantees rising damp.
Also heard as
- damp-proof course
- DPC