Render cracking - worried indicative of something serious

6 Jul 2020
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United Kingdom

I hve posted previously about some issues with lintels in the house (to rear of property) and looking at replacing windows and doors.

One of the things I had noticed was the render, there is a few cracks on this.

I have a structural engineer booked for next week but getting myself in a panic worrying there’s a more serious issue for all these problems.

I will enclose a photo of the front and one that shows a little closer. I have shown someone and they thought again might be to do with lintels?

What worries me is the swirling 3 lines above the front section that sticks out (quote faint but 3 similar lines above this section) and also the cracks above the ground floor window.

Does this look like might indicate something serious? I am looking to replace the rendering but want to make sure nothing untoward is happening first.

The render does seem hollow when you knock it and can see some faint lines similar on next doors but they have punted theirs more recently so not as obvious.

What with some cracking mortar above windows and slight cracking below windows getting worried something like subsidence or something very costly :(

Any guidance greatly appreciated before I get a inspection by structural engineer.
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Catherine L, good evening.

Could be you have indeed answered your own question?

The render does seem hollow when you knock it

In many. many cases what can and does happen is that render fails in small and large areas when rain water gets in behind the render because of cracks and micro cracks in the render, what then follows is that during the winter the trapped water behind the render freezes, that is natural, what then occurs is that when the water thaws, the water expands by up to 10% and it is this [so called] Freeze / Thaw cycle that pushes the render away from the wall, further [larger] cracks occur, and so it goes on, when tapped, the render sounds hollow.

Thank you.

I hope it is just due to weathering and age.

So now reading up on this, it appears it’s a minefield replacing the render. It’s a little confusing but am I correct that will need to adhere to building regulations to replace the render? Can see it says if replacing 25% is that 25% of all external walls? As it is only top half of front of property that is rendered.

If so need to go down thermal insulation route do I just need to do the top half that’s being rendered or the whole of the front wall? And likely costs for this?

I get the government want to make homes more energy efficient etc but just want to prevent any damp and replace like for like.

Also will I need to do party wall act?

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