Cracks after supporting wall removed

[Transylvania]

We had a downstairs supporting wall removed, acro props and steel beam designed by structural engineer.

A week later have noticed some cracks in the plaster and corner of the door frame upstairs, and the wallpaper has moved apart on the other side, and while the door will still close it won't stay shut like it used to. This is just beyond the end of one of the padstones at the end of the beam.

Is this serious? Is there likely to be further movement? Don't want to remove the plaster to see if the brick wall itself has cracked but will if necessary.

View media item 83183
View media item 83184

 

[tony1851]

Unlikely to be serious.

There are a few reasons why the crack might have developed:

1. Is the steel beam of adequate size for the job? It should be if designed by an SE, but sometimes they forget to allow for the inevitable slight initial deflection under the dead load of the structure.

2. Was the builder careful in propping - and particularly in removing - the temporary supports? He will swear blind he was, but who knows?

3. Is the wall supporting any load in the roof space (such as a purlin prop), which the SE may not have taken into account?

Don't necessarily go blaming anyone, as a little cracking is inevitable when doing structural work, though this may be slightly more than one would expect. Just get some filler in it and adjust the door catch and perhaps forget about it.

 

[Transylvania]

Beam was SE designed, can't see it being the wrong spec, and there's nothing really connected to that wall up in the roof (the wall is in the middle of the house).

I came home Monday night to find the props installed and the supporting wall gone; Tuesday night the beam was installed on padstones and cement and the props were still there; Wednesday night the props were gone, so don't know if that's sufficient time for everything to set.

As long as the pictures didn't raise alarm bells (like it did with me when I first saw it) and the cracks don't get any worse then I'll probably take your advice.

 

[Agile]

I would usually leave for at least three days to set even during the summer.

But in the recent warm weather cement really does harden very quickly.

When I worked in the Arabian Gulf they removed the formwork from reinforced cement floors the next day. But then the daytime temps were close to 40 C.

Tony

 

[Transylvania]

As time goes on I'm also noticing more and more squeaky/loose floorboards near this wall - the joists run parallel to it and I'm worried that one of them is shifting and causing the floorboards to loosen up. There are also some boards at a noticeably higher level than their neighbours, which I'm fairly certain wasn't the case before.

There's carpet all across the landing and bedrooms so I can't easily access the boards to see what's going on, but is this paranoia (ie the more I look for loose boards the more I'll find) or is this another 'expected' symptom of structural work?

 

[ree]

After the installation of a lintel, if at any time a door or window has opening difficulties then the installation should be investigated - preferably by whoever installed the lintel. We assume that the lintel is an RSJ?

Why not lift the landing carpet, and post pics of whats there - loose boards or any skirting movement.

And then, if you can see the lintel from above, lift some of the landing boards for a view of the lintel packing - wood, slate or a mortar bed? And is the lintel plumb vertical. And how are any joists bearing on the lintel?

Feel the wallpaper(?) on both sides of the supported wall - feel for any jutting plaster

Post pics from the room below showing the knock-thro and the position of the lintel above.

 

[CambridgeBrummie]

Have you got Building Regulations approval? Was this inspection by the BC Officer?

Sounds like some localised movement but should be monitored.