joing damp membrane

[nelliedee]

Hi
We are having problems laying the damp membrane, we have a manhole, pipe work and a Nib to cut around whilst laying it and we are frankly making a mess with it. Is it ok to patch the membrane, around awkward shapes? taping it as we go?
Nelliedee

 

[noseall]

just cut the membrane with a stanley knife. for instance, if you needed to cut around a square manhole simply slice the polythene from corner to corner, creating an an x. then fold them back. room corners can be 'dog eared'.

tape the joints with gas tape/duct tape/gaffer tape.

use boards or bricks to weigh awkward angles down.

 

[^woody^]

I doubt the water table is ever so high as to cause a typical extension floor to become damp.

The membrane is a good insurance policy, but don't expect ground water to come spurting through any slight gaps in the membrane. Basically, don't worry too much

Forming the corners is very similar to how you would probably wrap your Christmas and birthday presents.

And don't say you are Jehovas Witnesses

 

[nelliedee]

Thanks for your advice, we have already cut the x on top of the manhole but once we smoothed it down the sides of the MH, it is now cut level with the sand!!! thats why i wanted to patch this bit with an off cut of membrane.
Nelliedee

 

[nelliedee]

We probably have the highest water table in the south... We thought that this membrane would be soooo easy!!!!! mind you, hubbys a cabby and i am just a housewife,, enough said.
thanks for your help
Nelliedee