changing from wood to steel garage frame

10 Mar 2013
Reaction score
United Kingdom
hi got planning passed for a lean to garage with timber posts and beams to support the roof
a builder has suggested steel rsj beams supported on the external walls to save the use of support posts
the garage length approx 5.8m from memory is this span possible withous to huge a rsj
then use the same 200 x 75 rafters to support the box profile roof or add a 3rd beam alone the length to allow smaller rafters?
garage width is 4.4m
if calculations were obtained and building inspector was happy could the build be amended without new planning approval
Sponsored Links
after checking plans distance between walls is 5.3m plus the amount that would rest on both walls
So long as the size doesn't change and the overall design doesn't change wildly then don't worry about it.

BC will likely expect calcs for a steel that long, not convinced a steel would be easier, it would end up about 250 deep I'd guess. Just getting it off the lorry and hauled up into position would be a challenge even for a couple of burly of builders.
Sponsored Links
thanks freddy builder just thought it would save us having 4 150mm timber posts down both sides
any advice is welcome

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local