Diagonal wall blockwork

[aroberts34]

This is the plan view of a diagonally arranged doorway between two block walls. 1 square = 1 cm. The orange rectangles are 100 mm padstone allowance for the lintel and the green is the opening.

I am using medium density concrete blocks 44 x 21.5 x 10 cm laid with the 44x10 face down. Do I have to use squint bricks to make the 45 degree corner (I can't find squint blocks)?

Can I just lay the lintel here as normal or would there be problems due to the short length of the wall stub?

 

[jeds]

This comes down to loading on the wall and how much abuse it might get in service. You could possibly cut your own squint ends but the bonding will be minimal and the joint will be weak. You'd get a more stable result in studwork.

PS. other ideas; use bed joint reinforcement (although there's still not a lot of surface area) or build in 140mm block.

 

[aroberts34]

Wet room so I wanted masonry. I would use 140 mm blocks if the only alternative is stud, but very space constrained so would prefer not to.

The grey bits in the view above are partly existing walls, constructed of aerated concrete and hollow clay blocks in alternate rows and this is very weak stuff. My plan was therefore to cut back the two 'piers' on either side of the door by enough to tooth in 1 or 2 block lengths of medium density blocks, and include the 45 degree bends and stubs (stubs supporting the lintel) with this new blockwork. Without something tying the two piers together, I thought that they would still be unstable even though they were partly strengthened by the new blockwork. I hoped that the lintel and course of blocks above it would help to tie together the two piers.

See sketch below, doesn't show correct number of courses etc but you see what I mean:

If I managed to find angled blocks for the corners instead of using squint blocks, do you think this would greatly improve things? Not sure what the name is (maybe dogleg blocks) but with a cross section like below. Perhaps cut some (half height) out of regular blocks?

 

[jeds]

If it's not load bearing it comes down to a small risk. If you're up for that, then give it a go.

I think it would be a better joint if you did not try to bond the blocks. Lay the walls with angled ends (leave some mesh sticking out for the angles) and lay the angles against wall starters - or fishtail ties.

 

[aroberts34]

Do you mean use a wall starter or other metalwork at each 135 degree bend, instead of interlocking the blocks (e.g. with doglegs)? Can you explain why this should be stronger?