Internal wall knock through

17 Feb 2015
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United Kingdom

I am creating a opening in a internal load bearing wall 1200mm, applied for building regs and had a chat with the LABC. They dont want calcs just a suitable size UB or Catnic.
I would rather use a UB due to being tight on the height above the door. Problem is no one is able to tell me what size to put in. The council dont want to tell me before ive installed it as they charge for that. But will assess it once its in for suitability.
As i have limited time and funds is a box catnic (standard duty) a easy solution?
Or is there a standard size UB to cover this sort of situation without getting calcs?

The wall (medium block) supports the end of floor joists with a span of 3180 and 4400. Two celcon walls sit on the first floor. Is there a UB capable of taking that lot? without getting calcs done?

Thanks for any input.
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Thanks for the input tony.

Had a quick chat with LABC about when they want to visit, and mentioned that size didnt get chance to explain much before he said no problem at all.

Got a quote on the steel turns out i paid more for the scaffolding boards to do the job than the steel will cost!

Out if interest what span (in this scenario) would you use with that steel before getting calcs / thinking it may not be ok?
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+1 to the above.

In fact, on that span, you could probably get a way with a timber lintel - something like a piece of 4" x 4" fence post would almost certainly do. Most pre-War houses have 4" x 3" timber lintels over internal door openings.

Problem is that your inspector would ask for calcs for it, which would ultimately make it more expensive than using a steel beam :LOL:
picked up the steel today, will let you know how it goes.

Another question for you gents, I will be fireboarding the steel, the opening will have a set of wooden doors go in it, how do you expect the chippy to fix the head of the frame? Will it be best to sort of noggin the underside of the steel to give a fixing?
how do you expect the chippy to fix the head of the frame? Will it be best to sort of noggin the underside of the steel to give a fixing?
We would have the beam web and/or flanges pre-drilled so that we can fix timber to the beam, whether that be to the web or to the flange or both.

If you drill it yourself be sure to do it before you fit it in place.

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