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Heavy Duty 1200 Gauge Damp Proof Membrane (4m x 25m)
BBA-approved 300mu (1200 gauge) polyethylene damp proof membrane for ground floor slabs, oversite and tanking applications.
- 1200 gauge (300 micron) for Building Regulations compliance
- BBA approved for use as a damp proof membrane
- 4m x 25m roll provides 100m² coverage
- Suitable for beneath concrete floor slabs and oversite
- Impermeable barrier against rising damp and ground moisture
- Can be lapped and taped for continuous protection
Overview
1200 gauge DPM is a Building Regulations requirement beneath concrete ground floor slabs in the UK. It provides an impermeable barrier between the ground and the slab, preventing rising damp from reaching the floor finish. The 4m x 25m roll size is practical for domestic ground floors, providing 100m² of coverage per roll.
In-Depth Look
Every new ground floor slab in the UK needs a damp proof membrane beneath it. The 1200 gauge (300 micron) DPM is the standard specification that building control expects to see, and it is one of those products that is invisible once installed but essential for the long-term performance of the building.
Why 1200 Gauge
Building Regulations Part C requires a damp proof membrane beneath ground floor slabs to prevent rising damp. The 1200 gauge specification provides sufficient thickness to resist puncture during construction while maintaining an impermeable barrier. Thinner membranes risk being damaged by aggregate or foot traffic before the slab is poured.
Installation
The DPM is laid over the compacted hardcore or sand blinding, with all joints lapped by a minimum of 150mm and sealed with DPM tape. It should be turned up at the edges to connect with the damp proof course in the walls, creating a continuous moisture barrier. Care must be taken to avoid puncturing the membrane during reinforcement placement and concrete pouring.
Verdict
1200 gauge DPM is a non-negotiable building material for any ground floor slab construction. It is inexpensive relative to the cost of remedial damp treatment, and getting it right at the construction stage means the floor will perform correctly for the lifetime of the building.
| Roll Size | 4m x 25m (100m²) |
|---|---|
| Thickness | 300 micron (1200 gauge) |
| Material | Black polyethylene |
| Certification | BBA approved |
| Compliance | Building Regulations Part C |
| Lap Requirement | Minimum 150mm, taped |
Who It's For
- Groundworkers and builders laying new concrete floor slabs
- Self-builders constructing ground floors to Building Regulations
- Extension builders needing DPM for new floor construction
Pros & Cons
Pros
- BBA approved — meets Building Regulations Part C requirements
- 1200 gauge is the correct specification for beneath floor slabs
- 4m width covers most domestic rooms in a single span
- 100m² per roll provides good coverage for domestic projects
Cons
- Heavy roll — requires two people to handle on site
- Must be lapped and taped correctly to maintain integrity
- Easily punctured during construction if not protected
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