The Brew Cabin

Posted: **Mon Jan 28, 2008 6:16 pm**

Hi All

Another novice here.

I have to build a 16m x 4m slab to situate a timber built cattery on. I've been led to believe that a DPM is not required or needed as the slab is open to the elements. The slab will have a limestone hardcore.

Is this the case or should I use a DPM?

Many Thanks

Posted: **Mon Jan 28, 2008 8:09 pm**

D P M yes. the idea of a membrane is to stop the sub base sucking the water out thereby weakening the slab.

Posted: **Tue Jan 29, 2008 1:55 pm**

There should ALWAYS be a DPM beneath concrete. I've never yet heard a good argument to omit it.

The Brew Cabin

Building a slab