Bolts for steel beams

[akist]

I would like to bolt down a railing base over a steel beam, and it requires 12mm bolts. Ideally I would drill a 12mm hole into the steel flange, then fix it with a 12mm bolt from the top and a nut from below. However I do not have easy (or any) access to the space inside the beam and so I cannot place the nut.

I could use standard 5.5mm screws but they are not comparable to the 12mm bolts.

Another option might be to weld a steel bolts at the top of the beam ( rather than drilling it ) eg upside down, and place the nut at the top. Not sure my welding skills are up to scratch.

Is there any special fixing I can use?

 

[freddiemercurystwin]

Got some pics?

 

[akist]

It is for a balustrade very similar to this picture. The bolts go into the base channel before you slot the glass in. Need to be super strong about 380kg horizontal force at 1m height and at every one metre.

 

[freddiemercurystwin]

Not clear from that image, why don't you have access to the underside of the flange (if that's what you're saying)? Screws are no good, otherwise there'd be no point fitting the ring beam.

 

[akist]

I have access to the flange but it implies breaking up decorative and skimmed plasterboard sections (steel beam is boxed in). Also I have fitted noggins inside the web and if by bad luck I land on a noggin then its going to be even more awkward.

Just thinking aloud. probably I will have to remove the plasterboards to expose the flange.

 

[^woody^]

Whoever makes the balustrade should be specifying the fixing method to the structure, not some could do or maybe.

And they will also specify the waterproofing as this appears to be external.

And again presumably, building control will agree it all.

 

[jj4091]

https://www.s3i.co.uk/stainless-steel-screw-hexagon-washer-head-0915.php these should drill and tap their own hole into the steel beam but as woody says you need to follow the manufacturers instructions

 

[noseall]

I would like to bolt down a railing base over a steel beam, and it requires 12mm bolts. Ideally I would drill a 12mm hole into the steel flange, then fix it with a 12mm bolt from the top and a nut from below. However I do not have easy (or any) access to the space inside the beam and so I cannot place the nut.

I could use standard 5.5mm screws but they are not comparable to the 12mm bolts.

Another option might be to weld a steel bolts at the top of the beam ( rather than drilling it ) eg upside down, and place the nut at the top. Not sure my welding skills are up to scratch.

Is there any special fixing I can use?

We had to prep our steel beams, prior to cladding or plaster boarding etc with steel studs, ready to accept the glass balcony....

1587634060219212356492

• noseall
• 23 Apr 2020

 

[freddiemercurystwin]

https://www.s3i.co.uk/stainless-steel-screw-hexagon-washer-head-0915.php these should drill and tap their own hole into the steel beam but as woody says you need to follow the manufacturers instructions

Completely inappropriate for a balcony fixing.

 

[^woody^]

Rivet nuts are used for blind fixing in situations such as this. However you need to be mindful of possible galvanic corrosion, and as mentioned, the fixing method needs to be designed not made up.

 

[cdbe]

 

[freddiemercurystwin]

Again, not appropriate for a balcony fixing.

 

[akist]

I think I will simply have to take off (break up) the plasterboards and get access to the underside of the flange. Then new plasterboard, skimming, painting...

 

[Koolpc]

I think I will simply have to take off (break up) the plasterboards and get access to the underside of the flange. Then new plasterboard, skimming, painting...

Best to do it the correct way now.