Cracked wall - recurring

[u/Coffee2698]

Hi all,

Last year, I repaired this crack with filler and painted over it. Everything looked fine initially, but a few weeks later, the crack reappeared.

Now, around 7 - 8 months later, I've decided to open it up and investigate further (see photos). To my surprise, the crack appears to be approximately 6 cm deep. It looks like it's located where two bricks meet, just below a window.

There are quite a few cracks around the house that have reappeared after being filled, but this one seems a bit more serious and concerning than the others.

I know it doesn't look great at the moment, but I was wondering whether I could fill the deeper part with some repair mortar (the type that comes in a tube, similar to silicone/caulk), then finish it off with filler and scrim tape to help prevent it from cracking again.

I was also considering using Toupret Fill-Flex Flexible Filler instead of mortar, but the instructions mention a maximum filling depth of 1 cm, so I'm not sure it would be suitable.

Has anyone dealt with something similar? What products or repair methods would you recommend, and is there anything I should avoid?

For context, the house is only 6 years old and came with a 10 year structural warranty. Given that several cracks have reappeared throughout the house, do you think this is something worth raising with the builder or warranty provider? Or am I overthinking it, and is it likely just a cosmetic issue - not sure how a 6cm crack is cosmetic but I have to think about it.

I'd really appreciate any advice or suggestions before I attempt to repair it again.

Thanks in advance!

[u/PhysicsAgitated6722]

Are there related cracks on the outside?

[u/Coffee2698 → u/PhysicsAgitated6722]

No, I can't see anything on the outside. Everything looks normal. To be fair I haven't climbed the ladder to check it (I don't have one that big)..

[u/PhysicsAgitated6722]

Try taking a photo in the day and zooming in. If there are cracks, you will likely be able to see them. If there is, you need to get a structural engineer out sharpish, notify your insurance and contact the warranty provider given that crack is not looking good. It could well be something simple like your in a high clay area so there has been excessive movement caused by the clay shrinking more than usual but given houses hurt when they fall on you, I would not be taking any risks.

[u/experienced_invest]

You will have to open the crack out so it can be inspected. Make claim early as it might take 2 years to resolve. Hopefully you have evidence of stages showing it is getting worse. Hairline cracks are common but is this is 6mm then could be underlying issue with the build. We all know most new builds are appauling in terms of quality.

[u/Ghoshy24]

Cut the crack out in a V and use some of this: Toupret TTFIBACP01GB Fibacryl Fill-Flex Flexible Filler

Use that to fill and really push it into the crack, then sand and paint if you get it back again then it's definitely going to be from movement which you will need to get inspected but if theirs no crack on the outside wall it should be an issue

[u/ToriaLyons]

Foam it, fill it. (Foam will act like a glue and stabilise the area.)

[u/TA3865]

It's quite a big crack. Not terrible in itself if it's stable and just a bit of expansion movement. It probably needs helibars and a proper repair, before filling over.

[u/target-fixings → u/TA3865]

This is the way. Investigate the cause and, if stable, use helical bars to stitch, replaster/fill, paint, done.