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Beams in the loft are only 4" thick

Posted by christine mearing, on
Looking at a loft extension for a 50/60s bungalow - the beams which will support the floor are only 4" thick. Can we add an extra 2" piece on top of these to make them stronger -or is 4" ok?

David Price

Adding timber to the existing beams is not a solution.i would span the opening with new timbers beside the existing ceiling joists the timber will need to be sized using the timber span guides.why not employ a builder to do the floor as it may require steels to be inserted if the spsn is too long or you dont have suitable bearing Regards Dave price rew services

Philip Rouse

You will need to install heavier timbers supported off load bearing walls. Timbers will have to be sized according to span and distance apart from each other. You should speak to an engineer or council building control officer first
Edward Thompson

Edward Thompson

Hi Christine the beams you are talking about are only ceiling joists and would not be suitable even if you fixed 2" on top. As mention by a previous response the size of joist for a floor is determined by the span from one supporting wall to another.Consult you local building control who will be happy to give you advice.Thanks. Ed.
Dave Claringbould

Dave Claringbould

No I'm afraid you can't do that, but it all depends On what structural walls you have below and the span of These timbers, will give you a free survey of you Like, or you can contact your local building control It also helps if you can go to your local library and get A copy of the original drawings from the house,Dave DC builders
Michael Tucker

Michael Tucker

Hello Christine, It's to risky giving advise on this subject with out seeing it. Best to get an on site survey/quotation done, this is a free service to you and you will get 3 quotes. Simply post your job onto rated people's site. You are not obliged to go with any of the quotes- but ever job that's posted is paid for by the relevant tradesmen.if they contact you that means they are interested in your job. If one of them are awarded the job then great news for you both. ratedpeople.com Regards Michael

Andy Thornton

What you are trying to do should be done by a professional if you are trying to make a loft conversion to building regs. The process requires possible steels and structural calculations. I would also recommend you at least have your conversion drawn up by an architect. Andy

Michael Riordan

Chrisitne no this would not be passed you really need to up these timbers to 175x47 c16 at least to be acceptable depending on your spanning areas . steel support beams will need to be inserted then the new beams layed into them unless your engineer has put a design forward for your calculations for weights and stress, points as part of building regs/ plans thanks Michael

BARRY MOORES

Hi Christine This is not a simple job for a DIY person, the correct building practice has to be used as your building control may ask for steel beam for timbers to sit on etc. hope that helps Regards Barry
Miroslaw Mierzwinski

Miroslaw Mierzwinski

Hi. To meet new regulation unfortunately you can't use existing 4" joists to take the new load from the loft. You need to speak with local Building Regs. and hire structural architect to do structural drawings and calculation for steel beams. Regards. Mirek(c&gbs)

danny winters

Hi 4" joists are not thick enough will need to be at least 8" to meet code you will most likely need to insert steels to carry new floor joists please dont just guess what is needed to carry the load my advise would be to employ an architect this way all the the guess work is removed will save you money in the long run regards Danny
gregory mckenzie

gregory mckenzie

sounds like you will need to some steels in as the 4inch joists are really only designed to hold the weight of the ceiling adding 2 inch will not surfice you will need a engineer or someone from council building control

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