Chased cable and insulated plaster board

Inviere

Hi all,

I'm looking to sink a power cable into the wall to hide it, but one of the walls is a thick insulated (foam backed) plasterboard.

Whta would be the best approach here? I know with regular plasterboard, it's a relatively simple job with a Multitool, but with the thicker insulated stuff, I suspect the foam backing will just retain any segments I try to cut out.

Any ideas?

10-10-20

Hi! Yes, you can do it on insulated plasterboard alright. The insulating foam will come away from the plasterboard layer with some prying, it's not excessively adhered. You can then cut into the foam as required and then try replace the same plasterboard segment and skim over the top of it again.

Inviere

https://www.boards.ie/discussion/comment/122300849#Comment_122300849

Ah, sounds relatively handy cheers. As an aside, should I be using oval conduit for an electrical wire in this case?

10-10-20

https://www.boards.ie/discussion/comment/122300980#Comment_122300980

Oval, yes probably if it will fit the required wires. I was doing this last week for some network and HDMI cables and I ended up buying a wire conduit from woodies instead which was much larger and would take a HDMI head without issue. It's now buried in the insulation layer (and I forgot to take photos).

https://www.woodies.ie/d-line-1m-length-trunking-50x25-black

Inviere

https://www.boards.ie/discussion/comment/122301272#Comment_122301272

Cheers, appreciated. Did you have any trouble leveraging the plasterboard away from the foam backing?

This is for an external garden light, so I'm thinking 1.5mm t&e cable like this:

https://www.screwfix.ie/c/electrical-lighting/cable/cat8960001?cableproducttype=twin___earth&conductorarea=1_5_mm_

And then something like your link to route the cable then along the wall as it'll need to go horizontally inside the house:

https://www.woodies.ie/d-line-2m-length-trunking-16x08-half-round-white?objectId=93297&queryId=3b01b55623490463f695ceb43ccca275&indexName=prod_default_products

10-10-20

I was doing that job when the insulated plasterboard was still on the floor, so I was working from behind. But I have done similar by levering the board from the front. Just takes a bit of force and sometimes the plasterboard can crack or turn to dust… just keep at it. 👍️

randombar

Hi Lads, this post came up on my search but a question for those who might know.

I see plasterers put on the insulated plaster nowadays with adhesive.

Just wondering if people use foam at all? I'm guessing it's cost prohibitive to do a whole garage.

Getting the consistency right mixing is one of my weak points.

10-10-20

https://www.boards.ie/discussion/comment/122329105#Comment_122329105

Hi, the adhesive is the foam stuff in a can - it's specific to adhering insulated plasterboard. You just apply it in beads and not too excessively. I was getting just over 2 full-size boards (2.4m x 1.2m) per can.

It can be pricey and you'd need to check if the background (wall condition) will take the adhesive - but this is also true of dot & dab adhering also.

randombar

https://www.boards.ie/discussion/comment/122329343#Comment_122329343

Looks like a bag of adhesive does 2 boards @ 20 per bag

You're getting 2 boards @ 10 per can

It actually looks cheaper at the moment!

Inviere

https://www.boards.ie/discussion/comment/122300849#Comment_122300849

Got this done today, many thanks. Marked out with pencil, bosch multitool, shapes cut exactly as needed. The plaster shapes then came out of the wall without much fuss, cable trunked and sank, and plaster strips refit and filled. I'll sand them tomorrow and another coat of filler before painting. Chuffed, thanks again

10-10-20

https://www.boards.ie/discussion/comment/122332210#Comment_122332210

Well done!