TP10 and cable

[Horsecarver]

I am installing insulation in the walls of the kitchen, using 75mm TP10 in a wooden framework, covered with 12.5mm plasterboard. There is an approximate 25mm air space behind the insulation for cables, radiator pipes etc. but of course at the switches/sockets, the cable has to go through the TP10. I guess I'm being a little paranoid, but I'm looking for reassurance that having the cable in contact with the insulation for a couple of inches won't cause any problems with overheating. Any advice wold be appreciated.

 

[sterose]

I am installing insulation in the walls of the kitchen, using 75mm TP10 in a wooden framework, covered with 12.5mm plasterboard. There is an approximate 25mm air space behind the insulation for cables, radiator pipes etc. but of course at the switches/sockets, the cable has to go through the TP10. I guess I'm being a little paranoid, but I'm looking for reassurance that having the cable in contact with the insulation for a couple of inches won't cause any problems with overheating. Any advice wold be appreciated.

1. What type of material is TP10? Certain materials leach the PVC (i.e. they destroy the sheathing on the cable by absorbing the plasticiser out of it.)

2. Assuming that it is a safe material for cables to touch, there is no harm in a couple of inches.

Either way, consider using conduit through the insulation.

 

[sterose]

Sorry, it posted twice.

And by the way, paranoia is a good thing with DIY - i have it, and i've never had an accident becuase i'm careful and think things through.

Some other people are not like us...

 

[Horsecarver]

Apparently it's a "high-performance rigid urethane insulation", (typically manufactured by Kingspan or Eurosarking). Thanks for the advice - I'll consider the conduit option.

 

[ashten]

Apparently it's a "high-performance rigid urethane insulation", (typically manufactured by Kingspan or Eurosarking). Thanks for the advice - I'll consider the conduit option.

Is it coloured? i.e. is it a non flamable type? Are you using a breather membrane? Is the cavity you mention to be ventilated? Is the timber you are using treated? What is the construction of the existing wall?

You do not explain why you are doing this. Are you following a manufacturer's detail? What U value do you hope to acheive?

You will need to be very careful, otherwise you will affect the dew point and could cause condensation on one of the surfaces (even inside the cavity) which would more than likely cause rot.

These are complex matters and need to be considered from a technical standpoint. Take great care and preferably seek advice.

 

[Horsecarver]

I'm basically following the procedure shown at http://www.cgltimberframes.co.uk/uvalues.htm under the heading "89 Stud Wall with 90mm Batts and Kingspan TP10 " and I'm doing it because the kitchen is like Ice Station Zebra in winter. (It can get pretty cold in Aberdeenshire. The modern extension to the property has the standard pink mineral wool insulation in the walls and is quite warm).

The old part of the house is single storey, traditional Scottish croft style, with walls of 2'6" thick granite. I'm replacing the old 2" x 1" framework with 3" x 2" treated timber and leaving a 1" - 2" air gap behind the insulation, where pipes/cables can be run.