Clay Lump Repairs/Advice

[MudPies92]

Morning all,

I'm new here and looking for advice on clay lump repairs. I'm looking at acquiring a barn and I have fallen in love with a plot, it comes with planning permission which is conditional on using the the building materials outlined in the architects plans, which retain a lot of the original clay lump wall. It's clear that there are a lot of cracks internally in the clay lump (mostly above lintels). There are already patches with ordinary brick and cement render which I guess would require removal. I would most likely buy it and then sit on it a while so I can do some workshops/classes on clay lump, however I was wondering on the face of it, is it likely a repair job or will it basically need rebuilding?













If the walls are going to require a full rebuild, I would most likely approach the council for comment on trying to save external walls and use blockwork for internal so as to keep the character.

Any comments are very much appreciated.

Many thanks,
Simon

 

[aockenden]

Personally, I don't look at that and think those walls need a complete rebuild. Possibly just replacing some lintels and then trying to stitch up the cracks, or possibly localized rebuilding of the cracked sections. Our stone cottage had a large bulge and crack on the front wall, and another crack going up a gable. Both were long-standing historic problems, not currently moving.

On the gable end, we had a local building team stitch it up (basically insert stones across the crack and do lots of pinning / wedging / firming up on all sides) and then lime-rendered the entire gable wall (with an embedded fibreglass mesh for extra strength). That end of the house then got enclosed and supported by a new-build extension which further reinforces and stabilizes everything.

On the front wall, we wanted to keep the stonework exposed so we had the same local building team rebuild a vertical column of the outer-face of the stone wall about 1.5 meters wide, from ground to gutters, and rebuild it using lime bedding mortar to take out the bulge and the crack. I'm pretty hard on the tradies in general, but I have to say they did an excellent job and you can't even tell that section has been rebuilt or that there was ever a big nasty cracked bulge section there.

So long story short, there are definitely ways to locally repair cracks without needing to rebuild the entire wall, inside and out.

It looks like a fun project and definitely worth trying to save everything possible!

 

[Cubist]

From the little I know of clay lump / cob (adobe) construction, repairs to cracks can be very easy provided the blocks have retained much of their structural integrity. Based on the photos I would suggest the biggest challenge would be how to go about replacing those old wooden lintels and in which order to tackle them. To my mind the lintels have already shifted due decay of one sort or another and if not replaced they will pose an on-going risk to the structure. The key challenge will be how to support the adobe blocks above while the lintels are removed.

What is that coating on the exterior? If its a render of some kind it may be wise to leave that in place until the lintels are replaced, as it may help to stabilise the wall and reduce the risk of partial collapse in key areas.

 

[Kearn]

Looks like the inside has been tanked at the lower levels, that really needs to come off, the external render doesn’t look appropriate either, same requirement.

Cob/clay block can fail catastrophically when it does. I’m not saying it will. And the cracks in themselves look fixable assuming the root cause is dealt with first.

However, removing cement render is a bit of a specialist job, as often it’s become structural due to the underlying damage caused to the blocks. So it’s a very softly softly, slowly slowly approach.

Assuming the intention is to create a dwelling , with a first floor, then specialist consideration will be needed on how the floors will be inserted and supported…

Looks like a lovely spot, and as with all projects, enough time, patience, humour and of course, money, things can be done. The hardest part will be finding the right experienced trades to approach things correctly and help you through…