Help with RSJ size for flat roof

[Armz]

Hi people I am planning on rebuilding the flat roof of my garage as the current roof is rotten.

The size is 7.2m x 5.2m, and the steel beam will go across the middle giving a span of 3.6m from beam to wall. using an online span table i found I believe I require 8x2 c24 timber joists at 400mm centres.

My question is what size beam will I need to hold these joist?

I spoke to a local steel yard without going into much detail, who said 200mm high by 135mm wide light weight 25kg per meter. Would something like that do the job?

Many Thanks

 

[Mw Roofline]

The 8x2 @ 400 is fine maybe someone else can comment on the steel

 

[CraigC86]

What did you go for in the end - did you find a solution for the RSJ? I have a 5.5m span which needs 9x3 timbers at 400cc, so looking to do something similar with an RSJ to drop my span down to 2.75m (and go for 5x2 or 6x2s)

 

[oldbutnotdead]

Slight post hijack- have a look at jj i beams or similar engineered joists. Depending on how many you need they might be cheaper than the lifting solution you'll need to get 25kg/m steel on top of your building