Knock through | Steels calculation, one or two required?

[RonnyRaygun]

What you or I think does not matter. If someone designs something, then that's how it is built, not doing what the client or anyone else thinks.

Don't do it and there goes any insurance or negligence protection.

Go back to the engineer and suggest that the beams don’t need bolting together and can they change the detail?

 

[Dereekoo]

Don't do it and there goes any insurance or negligence protection.

Disagree, by that argument the SE could totally under design the required size of the beam and say as they were not bolted together ( which doesn't do anything for the structural capabilities of the beam) deny any responsibility for failure because some useless bolts were not installed. If that was the case he could specify anything he designed have a pink stripe painted on it and if this wasn't done deny all responsibility for any failures

 

[^woody^]

Disagree, by that argument the SE could totally under design the required size of the beam and say as they were not bolted together ( which doesn't do anything for the structural capabilities of the beam) deny any responsibility for failure because some useless bolts were not installed. If that was the case he could specify anything he designed have a pink stripe painted on it and if this wasn't done deny all responsibility for any failures

No he could not specify two strips of Tagliolini and require the client to conform to his specification.

Obs, he needs to design with competence. And if he designs the beams to be bolted then they should be bolted to conform to the design specification.

 

[SpaceWorm]

Ask your 'Engineer' is this his first time bless him

 

[tony1851]

Wouldn’t it be better to use a single beam with a top plate?
Or a pair of UBs rather than UCs? Can’t imagine a 203 UB would have a buckling issue over such a short span. Maybe even a 178x102...

Yes, if the single beam was one of the 203 UCs.
The OP's sketch of the original SEs design using a 152 UC would have needed checking for torsion, as presumably the inner leaf would be carrying more weight, particularly if it was a truss roof spanning front-to-back?

 

[baker332]

Hi all,

Thanks for the feedback, reading through the comments I'll check these off with the structural engineer.

One thing to point out, I made a major balls up here, the length is not 2.7 metre, it's in fact 3 metre knock out - meaning a beam requirement of 3.48 metre for 150mm bearing and 12.5mm x2 plasterboard etc.

Fortunately the correct details were specified with the structural engineer.

Would most of the comments stil stand with this new information? I.E Beam/pad size as mentioned in this thread.

Thanks for the support.

 

[baker332]

For two beams cost is coming in at around £500 inclu VAT Paint and delivery.

x2 152 x 152 x 30UC, S275 - 3480mm. 105kg each.

 

[baker332]

Mentioning costs, due to the earlier design change with a single beam, plate welded to the top. Which way would be most cost effective?

 

[baker332]

Ask your 'Engineer' is this his first time bless him

Hi Spaceworm, Is there concerns, should I use someone else? I'd hate to get this wrong and end up paying more in the long run? Or on face value would the designed beams be expected?