Where can I make service holes in web of UB

[garyo]

I realise this is fairly common practice, but is there a rule-of-thumb in terms of where I can safely make service holes in the web of a 203.102.23KGx5600mm beam - similar to the Part A joist notching rules?

Ideally I'd like a set of three 30mm holes in the centre of the web, around 600mm from the end of the beam.

Is there a standard approach that a BCO will accept or would he need me to demonstrate that my SE has designed the holes in?

How far from the ends of the beam must they be?
How far apart from each other should they be?

Thanks

Gary

 

[Nakajo]

Why not ask the BCO?

 

[^woody^]

I realise this is fairly common practice,

No it is not.

The bco won't know and there is no standard similar to joist notching. Ask the engineer.

 

[garyo]

No it is not

Half of the beam suppliers I've talked to have asked whether I want service or bolt holes... It's an up sell for them, but enough people must say yes to make it worth asking.

 

[^woody^]

Half of the beam suppliers I've talked to have asked whether I want service or bolt holes... It's an up sell for them, but enough people must say yes to make it worth asking.

Strange. I've never ever needed to do this.

And you are very unlikely to know where the services will be going or even where they are when you order a beam.

 

[tony1851]

With a 203x102 spanning 5.6m, you are near the limit for buckling resistance, so your load will be relatively low (a flat roof perhaps, or a short width of floor??)
In which case, the shear load on the beam will be low and drilling holes in the web will not be a problem.

 

[garyo]

you are very unlikely to know where the services will be going or even where they are when you order a beam.

Indeed. I don't know where so I've ordered it without any at all.

a flat roof perhaps, or a short width of floor

Its supporting one end of a 2.7m run of floor joists (Another identical beam will sit alongside and collect the floor joists from the other side)

They'll both be embedded in the ceiling and be an obstruction for the leccy and rad pipes. I could take a pretty painful route around through the eaves crawl spaces (bungalow) but compared to drilling some holes it creates quite a bit of plumbing work and I'd rather keep hot pipes away from the outside/roof of the house (yes I know insulation exists but....)

 

[Nakajo]

(To be fair, that's larger than 203)

 

[Ian H]

What about some 2x2 to lower the ceiling then go under it?

 

[garyo]

(To be fair, that's larger than 203)

Think of all the radiator pipes they could run in that car park if they wanted to though. They must have been planning ahead for when they turn it in to retirement flats.

 

[garyo]

What about some 2x2 to lower the ceiling then go under it?

The UB's will be hidden in the floor to avoid a step down, so if I batten lower to get the pipes under the bottom then I'd also need to batten approx. 50 square metres of ceiling if I wanted to keep a clean look.

 

[Ian H]

Ah, ours was only about 20mtrs so was pretty quick and easy.

 

[John D v2.0]

Half of the beam suppliers I've talked to have asked whether I want service or bolt holes... It's an up sell for them, but enough people must say yes to make it worth asking.

The beam supplier is just making what you ask for, they have no knowledge of the loads as the SE is designing the beam not them. If you ask for a 100mm square hole every 5 inches, maybe they'll do it assuming that's what the designer wants, but that doesn't mean it'll be suitable for the same tasks as an unholed one.