rsj

[680312]

I'm thinking of knocking a wall dividing a kitchen and toilet.
The span of the room is 14ft by 8ft wide.The wall to be taken down is 7ft,halfway,along the 14ft span.The joists are 7x2 and rest on top of the wall dividing the kitchen.Im going to replace with an rsj as a precaution and am wondering if i will need building regs or not.There is no wall directecly above only a stud wall 4ft from one edge

 

[Richard C]

It is a supporting wall & you’re doubling the span which will be above the maximum permitted for 7 x 5 joists. “Guestimations” can be very accurate for the experienced &, in your case, whatever you put in will most likely be enough but without calculations, how do you know what size beam is actually needed, steel or timber? More importantly you will need to show you’ve picked the right one! Even if you were under, maximum permitted span, its still controlled building work & you will need Building Regs approval which will also involve submitting calculations, BI inspection & compliance certification. You'll be on very dodgy ground if you can’t produce a compliance certificate when selling or in the event of an insurance related problem.

Don’t know the extent of the work your doing & how this affects the ceiling but have you considered beefing up the joists? You may get away with removing the need for a support beam altogether!