How do I run underfloor heating pipes through a cavity wall through the floor DPM.

[Jeffb]

hi all I am new to underfloor heating I have a problem detailed below.
I have a single floor extension adjoining a 2 floor extension so the partion wall is a cavity wall. I have block and beam floor, which will have DPM insulation the two areas have no door way. The manifold will be under the stairs in the 2 floor extension. My question is how do I run my underfloor heating pipes under the damp proof course in the cavity wall block work. The pipe work will have to pass through the individual room floor damp proof membrane up stands lapped under the extended DPM that protrudes out of the block work against the walls ?   How do I keep the integrity of the damp proofing ? Hope this makes sense . Thanks Jeff 

[joe90]

Not a cavity wall but I ran UFH pipes through internal walls by using 22mm overflow pipe in the wall, perhaps if you did this and sealed the pipe to the DPM either end with silicone or airtightness tape you would be ok.

[Russell griffiths]

You will need to insulate the pipes well to prevent the heat escaping into the cavity. 
 

I would core out a large hole and run the pipes inside insulation, inside a rigid plastic duct, seal the dpm with a mixture of tape and liquid dpm. 

[Jeffb]

Hi thanks for the replies , pretty much what I thought would have be done ,