Self Adhesive Waterproof Membrane

[glangri2]

I am building a cavity wall that has the Outside ground level about 300mm higher than the floor level inside the building.

I am planning on using 7kN Concrete blocks inside and out for the first 2 courses (below the outside ground level), and then going to the proper facing bricks on the outside skin, and Aircrete blocks on the inner.

I have already agreed with the building inspector about filling the cavity with concrete up to the outside ground level, and the positioning of the DPCs.

What he also suggested was that I should apply a self adhesive membrane to the inner face of the outer wall, before pouring the concrete in to the cavity. He suggested a product called Visqueen.

A quick 'Google' search bought up the info I needed ..........

http://www.visqueenbuilding.co.uk/product_detail.asp?id=50&sid=148

A bit more investigation uncovered the fact that this stuff is £176 for a 20m x 1m roll, so I started looking for an alternative.

Can anyone comment on whether this stuff .....

Ruberoid Plasprufe MP SA Membrane
http://www.dorseyconstructionmateri...P_PROOF_MEMBRANE_-_SELF_ADHESIVE_dpmrubsa.pdf

...... is comparable?

It is almost half the price of the Visqueen, and I am wondering why.

I don't mind paying for quality, but they appear to be very similar.

They need primer to be applied first, are 1.5mm thick, have a Polyethylene membrane and come as a 20m x 1m roll.

Any comments or info will be greatly received.

Gary

 

[noseall]

Use regular 1200g dpm.

 

[glangri2]

Use regular 1200g dpm.

Good (and cheaper) idea. I assume then I should just secure it in place somehow, fill the cavity with concrete and then lap it into the horizontal DPC in the horizontal DPC 150mm above the outside ground level !

 

[hotrod]

Good (and cheaper) idea. I assume then I should just secure it in place somehow, fill the cavity with concrete and then lap it into the horizontal DPC in the horizontal DPC 150mm above the outside ground level !

Yeah, that's the idea. You may find these useful-


Your internal dimensions will be different with regard to height between DPC and cavity fill and slab (because your int FFL is so much lower than ext GL).

hth

 

[glangri2]

This is what the building inspector suggested....

Untitled

• glangri2
• 5 Feb 2010
• 1

Note, it doesn't show the trench back filled with mud, but obviously that would be done.

This is the actual site so you can see the difference in ground levels...

Untitled

• glangri2
• 5 Feb 2010
• 1

 

[jeepman]

a good site is bluebay building products www.bluebaybp.co.uk they will help you out with everything you need to know they have a branch in luton and you can go and see what they have there to suit you