Advice on flat roof construction

[UKG]

Hello

I'm planning an outbuilding build approximate dimensions -

6.3 m x 7 m
(large double garage)

Can anyone advise on the type / size of joists required?

Is it best to have a central support also and running shorter joists off this?

Thansk for any advice.

Gavin

 

[noseall]

Can anyone advise on the type / size of joists required?

Will these be ceiling joists or floor joists?

Is it best to have a central support also and running shorter joists off this?

Depends on the above answer.

Are we talking flat roof or pitched?

If pitched, do you intend using the roof space?

If you just want a pitched roof with light storage then a manufactured truss roof would be a sensible solution.

A cut pitched roof would almost certainly warrant a central beam.

 

[catlad]

It will make life a lot simpler with a central post.

 

[UKG]

Hi

It's a flat roof. They are joists for the roof. It's single storey. No floor involved.

Thanks

 

[^woody^]

Advice on flat roof construction

Will these be ceiling joists or floor joists?

Are we talking flat roof or pitched?

Long day at the office matey?

 

[noseall]

Advice on flat roof construction

Will these be ceiling joists or floor joists?

Are we talking flat roof or pitched?

Long day at the office matey?

Oh come on Woodshave, you can't expect me to read a WHOLE post on a Tuesday.
Central beam still applies. Easi-joists (by "Trussform") may be an answer but they will be trés expensive and rather deep.

 

[UKG]

Thanks all,

For the central purlin would a 75 x 220 wood beam be strong enough? I can get this as long as 7.2 meters so it would reach.

Thanks


Also, can anyone recommend the best type of window to use on the roof at a 9 degree pitch and flat roof products?

A velux? A specific flat roof window?

Thanks again. Much appreciated.

 

[UKG]

Heres a couple of sketches of the building and potential roof truss pattern. Thanks

 

[noseall]

For the central purlin would a 75 x 220 wood beam be strong enough? I can get this as long as 7.2 meters so it would reach.

I doubt you will find a timber product deep enough. Your suggestion will not even be close. You need to have this building designed, especially as you are gonna need building regulations.

 

[UKG]

Thanks Noseall... any other suggestions?

Thanks

 

[UKG]

Hi catlad

Can you offer any further advice on a central post?

Size etc? What purlin sizes would then be required?

Noseall - can you recommend the type of professional I'd need to contact to get the calcs done?

Thanks again

 

[noseall]

Noseall - can you recommend the type of professional I'd need to contact to get the calcs done?

A structural engineer can have a wee look at your proposals, especially the roof timbers, steels, any large openings, wind loadings to walls and roof, foundation sizes (trees and shrubs nearby etc) and floor detail.

 

[^woody^]

Err, that's not a flat roof

Have some trusses made

 

[noseall]

Err, that's not a flat roof

Have some trusses made

See Woods, I ain't so daft after all.

 

[^woody^]

A true prophet.