# design for a new workshop roof, help please.



## devonwoody (13 Nov 2010)

Watching Grand Design last week someone was using beams as per drawing below.







I have a workshop span of 5.5mtrs each side and I think I need 10"x3" beams to span, these are difficult and expensive to procure.

Could beams constructed as above be a solution with the centre depth portion being from composite timber?


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## jasonB (13 Nov 2010)

The only problem with making them yourself is that you would have to have joints along teh length. The made up I beams have the web from continuous lengths of OSB etc and the top & bottom members are finger jointed.

Maybe lapping the joints and doing the webs from say 3 layers of 10mm ply would work but could end up more than an off the shelf I beam

Jason


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## devonwoody (13 Nov 2010)

Thanks Jason, its a problem for me that will not go away without a big spend.

I am coming to the conclusion that I shall have to live with the present roof after all. 

I had a cheapish offer this year of £2500 for a new roof but the beams were only going to be 8x2 and I think that would lead to trouble. That did include two concrete lintels over the doors.


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## OLD (13 Nov 2010)

http://www.stapeley1.plus.com/build regs & calcs.pdf 
looking at table A18 you are correct 50x220 @400 or 75x195 @400. 
But is this the shortest span for the space and could you have a large beam (could be steel) then lighter stuff over shorter spans like old buildings used . 
All the above assumes a flat roof.


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## devonwoody (13 Nov 2010)

It is a square building so spans are the same either way.

I am not happy with the front and back walls (foundations ) the side walls are OK and have a pillar each wall but cannot envisage a steel beam on the weak walls. And fall must run front to back. 

It is a dream really, because at my age what use would I get for the cost involved, so I shall take the winter periods and be absent from the W/S.


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## OLD (13 Nov 2010)

Seems like what you need is heating .Gas (bottled) is easy to do but can produce condensation so you will have to air out the shop when not heating and keep a checking for rust, but it will get you out there and it warms up fast.


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