Erecting a new roof

[greekstuart]

I have to build my own roof on a derelict house in greece. The span is 7.2 meters and I calculate the spars will have to be 4.2 meters. It has to be clad in clay pan tiles. There is not a load bearing wall to hang any cross members on so the wall plate and spars will transfer the roof weight.

Question. What size wood should I use for the spars?

Will the roof stay up without cross members?

 

[noseall]

You may get away with 175mm x 50mm rafters at 400c/c, depending upon pitch.

But, you are gonna need some pretty beefy floor/ceiling joists!

Have you thought about using roof trusses, or is not an option in Greece?

Is it your intention to use the loft space?

 

[greekstuart]

Hi,

Thanks for getting back - first time I have used the site so I hope that I am replying correctly.

Manufactured roof trusses are not an option as most new / renovated houses use lots of steel and concrete rather than stone and wood. My site is also off the beaten track and so getting trusses delivered is a non starter hence building the new roof myself.

The dimensions of the building are 7.2m wide x 8.5m long. The walls are 2.4m high and a gable at each end another 2.4m high.

I have built a central pillar from floor to roof approx 4.8m high with a supporting wall at 2.4m on one side. This will break the roof length into two - 3.5m and 5m. I want to run two floor joists of similar length onto which I can attach roof cross members to give the roof some support as well as forming both a 'room in teh loft' and something to attach plaster board or wood for the ceiling.

What do you think now about timber sizes?

Stuart