How to patch behind old hearth?

[ConnorS]

 

 

Hello, I'm after some advice around how to make this area sealed up nicely. 

We've insulated behind the plaster where the fireplace and chimney are but want to make extra sure there's no drapht, and I'm not sure whether using some concrete to level out below the skirting board is worth the hassle. We'll be putting a rug and a couch over the concrete so wouldn't be visible regardless. 

[JacobZ]

Hi @ConnorS,

Welcome to the Bunnings Workshop community and thank you for your question.

I'd suggest you start by vacuuming the gap to remove any dust, sawdust or debris from the space. You'll want a nice, clean area to work with, as you'll be using an adhesive gap filler.

I would then suggest using Abelrod in a suitable diameter for the gaps under the plasterboard, to plug them up as best as possible. You are aiming to plug up and lessen the gaps before applying White Sikaflex 11FC Purform over the top. Make sure you apply a bead that is wide enough to cover the gap between the concrete and the plasterboard without any air gaps.

The combination of the two will seal up the gap nicely to prevent drafts. You can then put a skirting board over the top to conceal this filler.

Let me know what you think and if you have further questions, please don't hesitate to ask.

Jacob