What size RSJ for garage roof

[Johnboy54]

I thought the Building Regs office would have been a tad more helpful!

I'm building a single brick garage/workshop attached to the house for my dad. (Well, a brickie's bricking)
It's not square, being 12' at the back, 18' at the front and about 24' long.
I intend to span the middle with an RSJ 15' long.
(My dad just rang and said it measures 13' 6" across the middle. I live miles away and can't check that just now, but I'd reckon it should be nearer 15'.)
One end set into the house wall and the other on a pillar.
I'm putting 18mm OSD boards on the roof and Marley sticky-back roofing felt.
I'll be using 12' joists 6" x 2" to rest on the RSJ and end walls.

What size RSJ would I need?

Building Control say I would need to pay a structural engineer to calculate it?
The local scrap yard won't give me a rough price either until I tell him the exact size.
Anyone have an idea, or is it time for my dad to dip into his shallow pockets?
Thanks.
John

 

[Shytalkz]

Building Control say I would need to pay a structural engineer to calculate it?

You do. The BCO does not exist to give you a size, only to ensure that the construction complies with BRegs.

The local scrap yard won't give me a rough price either until I tell him the exact size.

Don't use s/h, its provenance is unknown, so it could have been overstressed in its past life. Let it go to be melted down and buy a new one c£150 plus vat.

Anyone have an idea, or is it time for my dad to dip into his shallow pockets?

Yes....and yes .

 

[Johnboy54]

Thanks for the reply.
I will take your advice and tell him to buy new, given that I now have a rough figure of £150.
I was hoping for a little more help, however, with regards to size.
I thought that with all the detailed advice I've sifted through on this site over the years, someone out there would have said, ' Done loads of 'em. This is the size you need'.
Or words to that effect.
I've about 7 days before I need the RSJ.
I'll wait a bit longer before asking him to shell out an unknown sum to a structural engineer.
Anyone?
Thanks.
John

 

[Bowness72]

It doesn't really matter if someone on this website gives you a suitable size. Building control will want to see a calculation to prove the adequacy of the beam specified, which you will have to pay for.

 

[Shytalkz]

It doesn't really matter if someone on this website gives you a suitable size. Building control will want to see a calculation to prove the adequacy of the beam specified, which you will have to pay for.

Yes, John, we SEs operate an illegal cartel, didn't you read any of Joe-90's posts?!!

 

[^woody^]

A couple of my local authorities will allow the BCO to approve beams of certain sizes in certain locations in a domestic property without requiring calculations.

Somebody must have already worked all the common sections out.

 

[Shytalkz]

There are safe load tables for all the steel section sizes - fine as long as you know how to work the loads out .

 

[Johnboy54]

Thanks for the replies -

Bowness72 - It doesn't ask for anything from an engineer or anyone else on the application form? It doesn't need planning permission, if that makes a difference?

Shytalkz - I may be a bit thick on this one, but I didn't understand what you meant? Is it some kind of 'in' joke?
Just read your second reply - Are these tables available to download do you know, or are they bought from somewhere. I'm not bad at adderuppers and takerawayers.

woody - My kind of guy! Just hope that 'somebody' reads it.

Thanks to all for your thoughts and time.
John

 

[Shytalkz]

Not an in-joke, but if you are not aware of Joe's rants, then it won't mean much!

203x133UB25 off the top of my head, btw

 

[chessspy]

C-mon Shyt Awks
you know the bretheren can do better than that for a brother in need.
(he might be a future convert to the broderbond).









not so much a religion, more a bunch of cults

 

[Shytalkz]

Roflol

 

[Johnboy54]

Hell fire, Shytalkz! You're answering my posts faster than I can edit them!
Thank you so much for those measurements.
You've made an old man very happy.
And my dad.

chesspy - appreciate the encouragement.

Thanks all, again.
John

 

[Shytalkz]

No probs, but, seriously, steer clear of s/h ones.

If you need a calc to shut the BCO up, email me.

 

[chessspy]

The bretheren of the wall always come good for one of their own.
It's part of the creed of the wall.
The architect of confusion will be confounded.









Not so much. etc.

 

[Johnboy54]

Shytalkz - Your information was graciously recieved, and your offer of doing the calcs, if needed, was a lot more than I could have hoped for.
Thank you.

chessspy - You never mentioned which planet you call home?

Many thanks.
John