RSJ on padstones gap

[hungabunga]

Hi

We are removing a load bearing wall (supports first floor joists only) and have had a SE come in a do the calc. There is a door in the supporting wall and when we removed the load bearing wall we found a lintel across the door way exactly where the padstone would sit, thankfully it meets the specs of the SE calc. The only issue is as this was alreay in place it is about 6-8mm too low so is it ok to pack the gap with a strong mortar mix or should some form of shims be used. The beam is currently acro propped in place. My concern about shims it evenly distributing the load to the padstone and I also have no idea where to get shims.
If I do use mortar what mix should I use

Thanks in advance

sully

 

[Jackrae]

In days of yore, slate was used as shim ; flat, solid, grain runs the right way and should last for several millenium

 

[hungabunga]

Jackrae

firstly thanks for your quick reply, I am just a little concerned that getting the right thickness slate will be impossible. The beam it tight up against the joists and trying to tightly fill the gap evenly with slate is going to be a challenge to ensure it is make full contact with padstone and beam.
When you say slate I take it you mean real slate liek this http://www.travisperkins.co.uk/p/ravendale-brazilian-pre-holed-slate-250-x-500mm/209895/3893478

Thanks

Sully

 

[tony1851]

Shims are just small thin offcuts of steel; you won't find them at B&Q, but any local engineering firm would be able to give you a few small pieces.

 

[hungabunga]

do the shims need to be coated in that red paint too?

Thanks

 

[tony1851]

No; bit pointless, really.

 

[noseall]

Pop down to a local roof supplies and get some fibre cement slates and cut 'em to suit.

They won't crush.