Roof ridge on storage

[Derbyboy]

Why are every other roof ridge cut off at the bottom of this drawing:

 

[Derbyboy]

Anyone?

 

[Tjrex]

Because the extra load-bearing capacity may not be needed at the very edge, resulting in a more aesthetically appealing eaves?

 

[Derbyboy]

If you have cc60 on the roof ridges and saw off every other one, the span becomes cc120 for raw boards or battens (sheet metal). Feels like a fairly long span.

 

[joakim_j]

120 cc is standard.

 

[Rickard.]

Cc120 is the standard for roof trusses, I also think it's for the sake of appearance.

 

[Tjrex]

It is not common to have cc600 on roof rafters, usually cc1200 is used. Why this roof has it, we don't know. Must be weak rafters or accounting for a tremendous load.

Roof sheeting is not screwed into them but onto battens that lie in the other direction. Typically 45x70/95 unless there is a load-bearing under-roof. Dimension depends, among other things, on the snow zone.

 

[Derbyboy]

I will use cc30 and 45x145 with a span of 350 cm.

According to the wood guide, I would need to go up to something like 45x220 if I were to do cc120

Edit:

Snow zone 2

 

[Derbyboy]

You don't usually have cc600 on rafters but cc1200. We don't know why this roof has it. Must be weak rafters or if you are accounting for a tremendous load.

Roof sheeting is not screwed into them but into battens that run the other way. Usually 45x70/95 if there is no supporting underroof. Dimension depends among other things on the snow zone.

45x70 feels weak if you cut every other rafter at the bottom. It doesn't take much load for a 45x70 to bend when the span is 120cc

Perhaps I'm thinking wrong