Building regulations and bolting 2 RSJs

[mk1234]

My question relates to current building regulations for using 2 paralle RSJs.

The house is victorian with a 27mm wide wall (2 bricks, no cavity). I am knocking through the old exterior wall that now separates the original exterior wall into a newer a kitchen extension.

If I install 2 178 x 102 x 19 RSJs parallel to each other, will I need to bolt them together? The RSJs will be approx 220 wide when installed.

I have off-the-shelf padstones for either end of 300 x 215 x 215 and will build out the pier at either end to match the padstone (300mm) wide.

The RSJs have been purchased already and I do not want to have to drill them unless absolutely necessary, however have been told that new regulations may require them to be bolted together to stop any lateral movement. Has anyone had any experience of this? Will Building Control insist that this is done?

Many thanks

Martin

 

[mk1234]

The RSJs are 2850 long if this makes a difference.

 

[freddiemercurystwin]

Your structural engineer will advise you.

 

[noseall]

I have not installed a pair of steel beams in the last 20 years that were not bolted together.

 

[^woody^]

3 nr m10 bolts with mild steel tube spacers at 1/4 of the span will normally do

 

[DevilDamo]

Your structural calculations "should" also specify this, which is what your BCO would like to see.

 

[Static]

Its more economical to design the beams as bolted together as independant beams cant span the same distance and twist. If you didnt bolt them together you would probably end up with beams twice the depth.
As others have said consult your SE, its what your paying him/her for.