I have a question about a patio base. A builder has been around to look at my patio and is going to give me a quote. He has said that I need a DPC membrane under the patio, the type that is used for indoors. He said that it can be used outdoors.
I have only seen terram which lets the water through. When I checked with my local builders merchants they said that it shouldn't really be used on an outdoor patio but if it is then holes should be put in it to let the water drain downwards. I phoned the builder and asked if he was going to put holes in the DPC and he said "no" there was no need.
Could someone please give me a little guidance on this.
Thanks Eric
BTW, great site, I've spent a while on here learning all sorts
DPC / DPM is damp proof, doesn't let water through. If it is going outdoors you want it to let water through or it could end up puddling and in the winter it will freeze which will ruin your patio.
Builder is an idiot, don't let him near any job indoors or out
He said he would use a sub-base of dust and recycled glass, compact it, lay the dpm and then use a semi dry mix of builders sand and cement over it and lay the slabs on top.
I can see from your posts that the terram goes under the sub base and not on the top.
Tell this fella thanks for his time but not to bother with a quote and get a few others round to price it using the spec as mentioned above and nothing else.
