How should I fill this gap in the best way?

[JF.]

Hi!

Does anyone have an idea how I can seal the gap between the wall and the chimney breast? I was considering pushing in some chicken wire and then using some mortar. But maybe that will crack easily? Any ideas?

Thanks in advance!

 

[toolman77]

I would adjust the plaster so that it goes as close to the chimney breast as possible and then apply latex caulk. No idea if this is the best solution. You should repair the damage on the chimney breast. Alternatively, you could create an insert and repair the chimney breast against the wall. Then remove the insert and apply the caulk.

There will be movement at the transition between materials, so a latex caulk can absorb that movement without cracking. If it's a deep hole, you can insert insulation or a backing strip against the chimney breast.

 

[Gujje]

I agree that you should seal. However, I would not use latex since it becomes hard when it sets and will crack. Instead, use regular paintable construction sealant with a backing rod behind it (Sikaflex or Bostic Silmax are two well-known brands).

 

[toolman77]

http://essve.se/webcatalogue/fog-skum/969119-akryl-flex-25-hogelastisk-univerell-malarfog/

 

[JF.]

Thank you for the answers! The gap is at most 30mm and the essve joint builds up to 25mm, should one still take a chance and use it?

 

[Stadsfiskalen]

Wedge into a suitable piece of wood and join against the wood piece.

 

[toolman77]

Can you not replace the plaster strip on the short side of the wall with a wider one to avoid joints and transitions between different materials that can lead to cracks? Plaster-wood-stone will move differently and crack sooner or later.

 

[JF.]

Here's how it looks from the side. Sure, you might be able to let the plaster pass over the chimney on something and seal the small gap that arises.

 

[RoBo]

First check what the chimney sweep says about sealing there. It might have to be ventilated due to fire safety.