leave DPM in or use waterproofer in mix?

[mattu27]

Have install a new water mains that comes up through the garage floor in ducting.

I had to remove a section of the floor .5m2 which was laid on DPM, have tried not to rip this but it's got a few holes in it.

I've backfilled the duct with concrete to the DPM level but do I reuse the section of DPM that's a bit ragged or cut it away.

The concrete round the duct is fresh so will stick pretty well to the next layer, I'm planning on putting waterproofer in anyway but wanted some advice.

Shall I lay the new concrete on the old DPM or remove and go straight to the layer below?

Thanks

 

[oldbutnotdead]

Bit pointless ducting it then filling the ducting with concrete...
As for the rest, either reuse the raggy bit or drop a new bit in neatly formed round the duct. Long as you're doing 100mm thickness it'll be fine.

 

[mattu27]

Bit pointless ducting it then filling the ducting with concrete...
As for the rest, either reuse the raggy bit or drop a new bit in neatly formed round the duct. Long as you're doing 100mm thickness it'll be fine.

Haha, I've just re read what I typed. Does seem a little daft

It's a good 8" slab I'll be putting back in. Do you think a splash of waterproofer will make much difference?

 

[^woody^]

Drop some new polythene in and lap and tape it to the existing as best you can.

 

[oldbutnotdead]

Not much but chuck some in if it'll help you sleep at night