Foam gasket inserts

[Tony_Park]

Hi,

in an effort to make sure we don't suffer thermal bridging, is it possible to purchase foam insulation gaskets for installation in electrical sockets?

If so, where can they be bought, and how much do they cost?


Thanks
Tony

 

[Chri5]

Tony- What do you mean by thermal bridging ?

Are you concerned that a dry lined wall with sockets would allow cool air in to the room ? The depth of kingspan / celotex would prevent that.

I think you need to explain what you believe may be an issue, more fully.

 

[lectriclegs]

do you mean fire resistant intumecent foam

 

[ban-all-sheds]

http://www.lovemybubbles.com/butt-pads-foam.shtml

 

[ColJack]

just run the cables close to their max ampacity, should keep it nice and toasty in there.....

are we to presume that you are using conduit drops and want someting to fill one end of the conduit with to stop the cold air from the loft from dropping down the conduits???
some cotton wool at the top end would probably do it.. or even a little bit of loft insulation stuffed in the end..

 

[TonyW2]

BAS--you have a remarkably wide knowledge base or very strange & varied taste in research browsing.
Now I realise why my builders cleavage jeans look so inadequate compared to true professionals.

 

[Tony_Park]

Hi

By thermal bridging, yes, I'm looking at the transfer of heat from the solid wall of our house, past the 55mm insulated plasterboards travelling via the plug sockets buried into the plasterboard.

Due to the depth of the plasterboard with the insulation, we've not been able to find suitable drylinig boxes, and have had to use ordinary (deep) back boxes.

When I hold my hand close to some of the sockets, it's possible to feel a slight draft

Thanks
Tony

 

[Chri5]

Hi

Due to the depth of the plasterboard with the insulation, we've not been able to find suitable dry lining boxes, and have had to use ordinary (deep) back boxes.

Why ?

It's quite normal to cut the boards, remove the minimum amount of insulation for the back box and then hook your finger in and remove a 2 pence coin sized lump of insulation to allow the side tabs that hold the dry line box to close against the inner side of the p/board.

Was it a DIY job or did you use a spark ?

Since it's not going to be a retro / refit and you mention the metal boxes are deep set you need to confirm where the draft is.

Is it between the gap created by the box being over deep and thus there's an air gap between the rear of the board, or is it air coming thro the b/box knockout and fixing holes ?

If it's the 1st then filler or rockwool could be used to plug the gaps. If it's the 2nd then I'd suggest some sealant dotted around the knockout and used fixing puncture holes would be a half way to sorting it.

A more labour intensive method of resolving (1st) would be to remove the steel box, pad out the depth with wood and fix the b/box to the wood so the face of the box sits near level to the p/board face. Thus removing the gap. If there is a lack of insulation to the top, bottom, left and right sides this could be padded out with rockwool prior to steel box refit.

 

[karls2009]

You can get foam cut outs the size of you box (double or single not sure about dual) that are designed to prevent drafts ,contain fires and help with sound proofing. i couldn't tell you what these are called but we used to get them from newey's.

 

[ColJack]

backboxes tend to be 35mm deep.. so you cut a piece of 20mm thick foam board ( celotex stuff ) and put that behind the box and fix through that to the wall..
assuming you use plastic plugs in the wall then that will isolate the box from the outside wall and stop any conducted heat loss..

there's the extreme choice.. loosen the socket front and squirt the backbox with expanding foam and refix the front quickly.. but the foam may get into the internals of the socket then and prevent it's proper operation, not to mention the de-rating of the cables and any reaction / damage between the cable and the foam....