Unstable wall?

[cakeman72]

The photo below shows the cut end of a wall that is about 1m long. It isn't supporting anything above it. Before it was cut, it was buttressed by another perpendicular wall a couple of metres further towards the camera. But now I'm a bit concerned that it's going to be weak, because its quite thin and the hollow bricks and mortar holding them together don't seem to be that strong.

I'm thinking of putting a timber post at the cut end, bolted to the floor and to joists in the ceiling, and strapping that to the wall somehow. Maybe with some bolted steel plates (there is 1cm of cement render that could be chiselled off and then plastered over to accommodate the bolt heads etc).

Other thing to note is that I'm going to cut back (about 2 inches) the horizontal brick ribs in the cut end, from the ceiling to about half way down the wall, to make a void for a lot of electrical cables. This prevents me from cementing rebar or bolts into the holes in the cut end.

In regard to the timber post, do you think this is really necessary or am I overengineering it? What type of plates/bolts would you use?

 

[23vc]

These kind of partition walls rely on lateral support/being fixed at the top to ceiling joists as you’ve found, or they start swaying etc.
Shoring up the end with a vertical stud or two would work, and I’d probably look at a couple or three bent restraint straps run from the stud horizontally over the wall and chased in/plastered over.

Edit - having looked at the pic again it might be “locked in” fine with the plasterboard or the odd noggin at the top, I’ve had it where these can literally be rocked with your finger at the top. So depends how far you want to go / if it’s actually an issue

 

[noseall]

The photo below shows the cut end of a wall that is about 1m long. It isn't supporting anything above it. Before it was cut, it was buttressed by another perpendicular wall a couple of metres further towards the camera. But now I'm a bit concerned that it's going to be weak, because its quite thin and the hollow bricks and mortar holding them together don't seem to be that strong.

I'm thinking of putting a timber post at the cut end, bolted to the floor and to joists in the ceiling, and strapping that to the wall somehow. Maybe with some bolted steel plates (there is 1cm of cement render that could be chiselled off and then plastered over to accommodate the bolt heads etc).

Other thing to note is that I'm going to cut back (about 2 inches) the horizontal brick ribs in the cut end, from the ceiling to about half way down the wall, to make a void for a lot of electrical cables. This prevents me from cementing rebar or bolts into the holes in the cut end.

In regard to the timber post, do you think this is really necessary or am I overengineering it? What type of plates/bolts would you use?


View attachment 413150

That wall does not look like fun to work on or fix to. A post at the end would work as long as it is screwed to a ceiling member and angle bracketed to the floor. But securing it to those hollow blocks is not going to be easy.

If thickness is not an issue then secure a timber post (floor ceiling) that's at least as wide as the wall. Dab a plasterboard each side of the wall, so that it over-sails onto the post and screw it into the posts both sides. This will afford you some kind of service void also, rather than chopping into those horrendous blocks.

I suppose you could foam in some timber packers into those hollow pockets and then fix your 'wind post' to those.

 

[cakeman72]

These kind of partition walls rely on lateral support/being fixed at the top to ceiling joists as you’ve found, or they start swaying etc.
Shoring up the end with a vertical stud or two would work, and I’d probably look at a couple or three bent restraint straps run from the stud horizontally over the wall and chased in/plastered over.

Edit - having looked at the pic again it might be “locked in” fine with the plasterboard or the odd noggin at the top, I’ve had it where these can literally be rocked with your finger at the top. So depends how far you want to go / if it’s actually an issue

Well it doesn't visibly wobble when I whack it with my hand, and I needed a sledgehammer to demolish the part I've already removed. But I'm weak and skinny. It just looks dodgy to me, but I probably wouldnt notice if the end was plastered over and I couldnt see the brickwork. How strong does the wall need to be? ‍I dont have much intuition for that.

Thanks for the photo of the steel thats the kind of thing I needed to help choose from the bewildering array of builders metalwork. With your and noseall's alternative idea of just sandwiching the wall/post between two sheets of plasterboard , would the dot and dab adhesive be enough to have the desired strengthening effect?

 

[cakeman72]

That wall does not look like fun to work on or fix to. A post at the end would work as long as it is screwed to a ceiling member and angle bracketed to the floor. But securing it to those hollow blocks is not going to be easy.

I would probably use steel straps like it the photo above, position so the 2 rows of holes are straddling one of the internal ribs. I'd do a test drill to make sure it doesn't just shatter the brickwork. Then use bolts going through the entire wall. Although the alternative of sandwiching post and wall between 2 sheets of plasterboard would appeal if its going to be strong enough.

 

[23vc]

sandwiching the wall/post between two sheets of plasterboard , would the dot and dab adhesive be enough to have the desired strengthening effect?

Yes More than enough from what you’ve said. It’s just a partition wall, so as long as it’s stable enough not to move and show visible cracks you’re good