Padding out steel beam

[Dave Thornley]

I have a steel beam, PFC, installed under a first floor area. The thing is the joists holding up the floor above vary in depth and combined with it being an old property is a shall we say varying in shape. Two of the joists rest on the steel beam whereas others have a gap of a few mm to over 20mm.My solution is use steel packing plates for the smaller gaps and use plywood for the bigger gaps.
Would this be suitable? Attached is a drawing which might ex

plain things better.

 

[23vc]

Sounds sensible to me as long as it’s all packed and tight under every one.

 

[plastic_peanut]

Don’t forget to check the back end of the joists for movement.
It may result in them being jacked up or pushed down

 

[^woody^]

Jack the beam up

 

[Dave Thornley]

However much the beam is jacked up there will still be gaps plus the two that are not touching would need cutting.

 

[^woody^]

No, jack the beam up untill all, or most of the joists touch it

 

[Dave Thornley]

As stated 2 are already touching so no room for manoeuvre to jack it up further.

 

[^woody^]

Wont the two touching push up then?

 

[John D v2.0]

We were specified to use steel shims or hardwood packers for this exact situation.
For the ground floor joists with short spans i just used the cheap plastic ones you use for Windows and doors.

 

[Dave Thornley]

No they are like all the rest nailed to the floorboards above. There iused to be an old oak beam above that was all shapes under the sun hence the varying gaps. Even with the oak beam it appears some of the joists never rested on the oak beam.

 

[Dave Thornley]

We were specified to use steel shims or hardwood packers for this exact situation.
For the ground floor joists with short spans i just used the cheap plastic ones you use for Windows and doors.

I could use oak as the wood packing as have got lots lying about. Whatever I use will need to be at least 50mm (width of joist) x 130mm (width of the steel beam).

 

[Notch7]

is there anything to be gained by using anything harder than the joists themselves?

I wouldve thought plastic shims would be fine -how much load can there be

 

[23vc]

If you jack the whole lot up to make the underside of all of them touch the beam, won’t you be in for a bit of a shock when you go upstairs to find a landscaped floor?
I’d pack with at least wood, can also use slate

 

[Dave Thornley]

is there anything to be gained by using anything harder than the joists themselves?

I wouldve thought plastic shims would be fine -how much load can there be

I would have thought not myself hence my suggestion to use plywood. Probably end up with plywood and and slight differences made up by steel shims.

 

[Dave Thornley]

If you jack the whole lot up to make the underside of all of them touch the beam, won’t you be in for a bit of a shock when you go upstairs to find a landscaped floor?
I’d pack with at least wood, can also use slate

I physically cannot jack it up so all touch the beam themselves hence the need for packing pieces.
Being a 16c property uneven floors are the norm here.