Membrane for pic - Pic

[KeithW]

Hi,

I'm newly registered but so far I've found this site to be really useful and informative. Thanks.

I've just embarked on getting information and quotes for imprinted concrete for my drive and I'm already getting nervous about handing over large amounts of dosh and not getting a satisfactory job, judging from a few of the well chosen comments on the site.

I have one particular query at present, about the need for a separation membrane between the sub-base and the concrete. Can't get a straight answer if it is a dpc or a "slip" membrane or if it is needed at all. Any straight answers around ??

Cheers

Keith

[KeithW]

Sorry this post appears three times but when I tried to post it, I kept getting a screen saying server error. I assumed the post had failed. Seems to be some problems on the site. When I got back in, suprise, suprise all my posts had got there.

Aren't computers wonderful.

Perhaps someone could kindly remove two of them.

Hope this works - second attempt so it may appear twice !!

Cheers

[Tony McC]

It's not a separation membrane that's needed - it's a damp proof membrane (although there is an argument to be made that a damp proof membrane is a separation membrane, if you want to be pedantic about things!)

See the Concrete Hardstanding page for a fuller explanation.

I removed your 'bonus' posts.

[kesam]

Just done a course at PICS site and they recommend a simple layer of poly. Pleas ensure this is specd in your quote. One of the reasons is to ensure an even curing time in the concrete and reduce the chance of cracking. Be aware that anyone who promises no cracks is someone to be warry of, as its impossible to guarentee against. A good contractor will however do everything he can to minimize the possibility of cracks.

[Tony McC]

The "simple layer of poly" is a damp proof membrane. It has to be strong enough to resist accidental tearing when the concrete is placed. which is why we would normally recommend a 1200 PIFA (Visqueen) membrane.

As stated elsewhere on the main website, a DPM prevents loss of mix water, and so ensures the concrete is more likely to cure as designed and give the strength and durability required.