RSJ Help

[ROBO11]

We've been having a Dorma loft conversion done, the build included the need for 5 RSJ's.

One of the main issues we had been facing was freshly plastered ceilings cracking on the 1st floor, which effectively were directly below 3 of the 5 RSJ's.

I decided to rip the ceilings down, I found that not 1 of the RSJ's are sat on the Pad Stones. Packed up with numerous different things and 1 pad stone not bedded in. Believe it or not BC signed these off although I think they had been hidden at the time of approval.

I have a structural engineer coming out next week to advise on what's been done wrong and hopefully the best solution to correct.

My guess is the RSJ's will need to be supported one at a time with numerous props and the pad stones set at the correct height. Any advice would be greatly appreciated.

 

[noseall]

They all look well packed to me, although some packers and the packing leave a lot to be desired. We tend to put the beams in place then build the pad's beneath and snug. There is always a wee bit of shim room though..

 

[ROBO11]

They all look well packed to me, although some packers and the packing leave a lot to be desired. We tend to put the beams in place then build the pad's beneath and snug. There is always a wee bit of shim room though..

Are you serious? One of the packers has already cracked in half. See photo 5.

 

[Notch7]

One of the main issues we had been facing was freshly plastered ceilings cracking on the 1st floor, which effectively were directly below 3 of the 5 RSJ's

What sort of cracking?
Do you mean cracking at the plasterboard joints or screw head popping?

In regards to structural beams, there can be initial settlement which can lead to cracking if it’s not well packed or there can be long term movement if the supporting walls can’t take the load (or beam under specified).

A problem I’ve seen a lot of is construction that happen in the winter, the timbers are soaked, then when the warmer weather comes it all shrinks - that often causes crack in plaster and at skirtings and architraves.

 

[ROBO11]

What sort of cracking?
Do you mean cracking at the plasterboard joints or screw head popping?

In regards to structural beams, there can be initial settlement which can lead to cracking if it’s not well packed or there can be long term movement if the supporting walls can’t take the load (or beam under specified).

A problem I’ve seen a lot of is construction that happen in the winter, the timbers are soaked, then when the warmer weather comes it all shrinks - that often causes crack in plaster and at skirtings and architraves.

The plasterboard joints ceiling to wall in all the rooms

 

[noseall]

A problem I’ve seen a lot of is construction that happen in the winter, the timbers are soaked, then when the warmer weather comes it all shrinks - that often causes crack in plaster and at skirtings and architraves.

That appears to be the problem here. Those beams are one floor above the problem ceilings by the sounds of it.

 

[ROBO11]

That appears to be the problem here. Those beams are one floor above the problem ceilings by the sounds of it.

Correct, or they were before I ripped them down

 

[jacko555]

One of the packers has already cracked in half. See photo 5.

Any chance it was broken before packing? Poor photo but looks like mortar in the join?

 

[ROBO11]

Any chance it was broken before packing? Poor photo but looks like mortar in the join?

Honestly I don't know if it was broken before packing, they were hidden months ago. I don't think there is any mortar in the join but will check when I go home tomorrow

 

[Higgy28]

You ripped down your ceilings because of some hairline cracks???

 

[ROBO11]

You ripped down your ceilings because of some hairline cracks???

There was more wrong with the ceilings than just cracks, they hadn't used scrim tape, the plastered finish was appalling but most importantly the ceilings were 60-70mm lower than the architects plans

 

[Harry Bloomfield]

The pads and packer look fine to me, the only one in doubt, is #5.

 

[George_engineer]

It's not perfect but what's the possible failure mode here? So long as the packs aren't made of cheese I don't think there's much to worry about.

If you did want to go belt and braces then you could shutter and use non-shrink grout to lock everything into position. Even go with some fancy sika epoxy stuff. But it'd make a mess!

 

[Notch7]

The plasterboard joints ceiling to wall in all the roomsView attachment 280507View attachment 280508

Thanks for posting pics.

I’m not sure what’s going on with the plastering, looks rough to me.

the cracks between walls and ceiling arent much of a deal TBH, certainly not an indicator of structural faults like faulty install of structural steel work.

 

[ROBO11]

It's not perfect but what's the possible failure mode here? So long as the packs aren't made of cheese I don't think there's much to worry about.

If you did want to go belt and braces then you could shutter and use non-shrink grout to lock everything into position. Even go with some fancy sika epoxy stuff. But it'd make a mess!

My concern is how have they got the placement of the padstones so wrong? SE design was for the steel to be sat on the padstones not 50-60mm of paving slab, slate, steel shim or whatever else they could find to use as a packer. Is there no regs as to how much you can pack up?

It just doesn't seem right to me but that's a completely unqualified opinion.

I know they aren't going to fall down the main issue now is continued movement due to a cracked packer, 1 padstone not being cemented in place and some of the RSJ ends not being tied into the brickwork. I would rather try to correct now to avoid having issues later down the line. You may have just given me the solution, mess isn't an issue due to the house being empty.