Product Description:

Our DPC Polythene is a flexible damp proof course supplied in a 225mm x 30m roll, laid within masonry walls to stop moisture rising from the ground into the brickwork and blockwork above. The 225mm width is sized for 215mm walls, including one-brick-thick solid walls, 215mm hollow and solid blockwork, and double-skin garden and boundary walls, and it is used on retaining walls, garages, outbuildings, piers, and heavier structural masonry.

Walls of this thickness are often the ones most exposed to ground moisture. Solid garden and boundary walls, retaining walls, and freestanding piers typically sit in wet soil with no cavity to interrupt the path of water, so a continuous barrier across the full width becomes essential rather than optional. At 225mm, the DPC covers a 215mm wall with a margin to spare, allowing it to sit flush with both faces so moisture cannot find a way around the edges and rise into the masonry above.

Polythene DPC is lightweight, easy to cut with a knife, and quick to lay, unrolling onto a fresh mortar bed at least 150mm above external ground level with the next course laid directly on top. Joints and corners should be lapped by at least 100mm, and on buildings the DPC must link with the damp proof membrane in the floor so there is no gap in the protection. Keep it clear of render, pointing, and raised ground levels outside, which would let moisture bridge around it. On freestanding garden walls, a DPC is also commonly laid beneath the coping to stop water entering from the top.