How to repair cracks in brick wall?

[TJP]

Hi folks',

Firstly I appreciate there's a few posts asking how to repair cracks in brick, but my question differs a bit.

The cracks I have in my walls have formed due to a combination of both cement and clay bricks being used during construction. I have read that cement and clay shift at different rates, resulting in the cracks.

I read a reply from a team member stating that a combination of Earl's 1kg Concremate Expanding Cement + Dunlop 4L Premix Render Joint And Patch could be used for repairs. Would this be the case for me too?

Cheers,

T.

 

   

  

[JacobZ]

Hi @TJP,

If you have both concrete and clay bricks, then I would say you are correct that the expansion and contraction are the cause of the cracks, but I would consider having them assessed by a structural engineer or licenced builder to ensure the issue is not something more sinister.

Unfortunately, to fix the issue long term, it would not be as simple as just rendering over the cracks, as the different materials will still be there and will always be expanding and contracting at different rates.

Typically, you would use a specialised expansion bead that is similar to this PVC Plaster Expansion Joint that will allow for those slight movements of the different surfaces. Unfortunately, as this is a specialised product, you would need to source one from a rendering specialist. Due to the complexity, this might be one to contact a renderer for their assistance with. 

The cracking under the cornice is a much simpler fix. Simply cut out the existing caulk using a utility knife, ensuring you wear your protective equipment, especially a long work shirt and gloves. Once the caulk has been removed, you can apply a bead of No More Gaps to cover the gap, strike it off smooth and then paint over the top.

Allow me to tag @Dave-1 and @Nailbag to see what they think.

Let me know if you have any further questions.

Jacob

[Dave-1]

Good morning @TJP 

The plaster as @JacobZ has said happens with time and is an easy fix, I would check for leaks unless you know the house has moved recently (I have some appearing in the same location of my loungeroom after adjusting my floor as it was dipping) 

With the render between two dissimilar surfaces, I havnt had to do that so will follow along and see what members suggest. Depending on how big an issue it is I would be tempted to go for a "best fit" solution with the tag that you may need to redo it down the track. 

Dave

[TJP]

Hi @JacobZ @Dave-1 ,

Appreciate your insight, I must admit, I'm not surprised to hear you say that the fix for the cracks cause by use of different bricks is a major job. Put it down to wishful thinking on my part, thinking it was simple.

Will provide an update on how I go with the cornice repairs.

Regards,

T.

[Nailbag]

Hi @TJP 

I have had to repair quite a few older homes with this scenario. What @JacobZ has already suggested for both the wall and cornice is exactly how I would approach it.

Nailbag