Waggie wrote:Hi, looking at the comments I can see i'm going to get myself into a whole world of problems, when i spoke to my local council about this they set the parameters i.e 20sqmtrs @ max 2.5mtrs high, so i simply took this as a 4mx5m building @ 2.5mtrs high. they also stated that the max height was to include any roof coverings. I know i can purchase this sort of building but prices are out of my reach (well i just don't want to spend that much) and of course there's the internal height problem. i'm 5'10" so i naively thought that with the walls at 1.8m (5'10") and the roof rising off that there wouldn't be a height issue. I can jiggle about with the wall height and use 1.9m or 2mtrs which is about 6'3" to 6'6" but i have to keep the ridge below 2.5Mtrs and there seems to be the problem, not enough slope on the roof. so would you recommend I go for full planning permission? to gain height.
Did the council say if the 20sqm was the external footprint at ground level, the maximum overall Length x Breadth eg including gutters, the internal floor area or something else.
Provided the parameters they gave you (and the definitions used ) are acceptable to you then in your shoes, I'd not put yourself through the agro and expense of a planning application.
As earlier I suggest you draw out detail at wall plate level, using Mike's 145mm rafters, with birds mouth , the soffit and facia boards, roof deck and covering with the position of the gutter.
Do a similar section for the ridge, roof deck and covering and ridge capping. Put the top of the capping section 2.5 m above ground level, and your wall plate section with the wall plate at your 1.8m internal clearance offset to the side by a couple of metres.
Join up the rafter ends and you have the nominal design of the roof and the angles you originally asked about.
If you can do these sections in some sort of computer drawing package so much the better as you can move things about to try things out.
hth
Bob