Pipes run within cavity wall?

[Jdwood38]

Hi all,

Is there any reason, regulation or otherwise (aside from best practice) why pipes cannot be run within the cavity wall? I need to get 2x 28mm (CH F/R) and 2x 22mm (H/C) to a remote part of the house and currently have a large section of the cavity exposed due to having to replace flood damaged insulation and it would be an ideal route. Pipes would have no joins, would be insulated and then have the new wall insulation packed around them too. The alternative is to bury them in the floor which isn't ideal either.

The one thing I am aware of (I think) is that any pipes should be replaceable and whilst I appreciate that is a requirement on paper, the practice of doing so would be absolutely impossible. 28mm pipe being pushed through a conduit with multiple bends is just not going to happen.

Thanks in advance for any responses.

 

[Jdwood38]

Sorry, should have added that all are plastic, a combination of Hep2O for 28mm and JG for 22mm.

 

[denso13]

The hot and cold should be accessible and not embedded in the fabric of the building, as per water regs.

 

[Jdwood38]

The hot and cold should be accessible and not embedded in the fabric of the building, as per water regs.

Thanks Denso.

Does that include if within conduit? The 22's would be easier to replace.

Really struggling for any possible alternatives. The wall they need to cross has bifolds and the whole room has a pitched 'cold' roof so no cavities to run in!

 

[Jdwood38]

Could they run behind skirting board in a channeled out section as a possible alternative? Obviously skirting would need to be glued only and not tacked or screwed

 

[Jdwood38]

Sorry, hopefully final question as an alternative. Could all 4 pipes be run externally, above ground level in Armaflex, then an insulated box built around them, fitted with cement board and then rendered?