Triangular Shed Build - Roof Question

[woodblock13]

Dear All,

I hope everyone is well, I am trying to make the most of a small space at the bottom of our garden to create a bike/bin/tool storage shed but am struggling with the roof design. I would just like a simple mono-pitched roof but the triangular shape of the shed is making it hard for me to get my head around the problem.

I have used sketchup to create an initial model which you can see below and would hugely appreciate any suggestions you had to conquer the issue!

 

[Notch7]

You want the front to be level I guess.

Start your joists at the front and go back perpendicular to the front.

Then you will end up with a slope on the roof at the back - but the water will all run forward to the gutter at the front.

 

[big-all]

easiest way
polystyrene block
rectangle the full scale size cut the roof angle
cut to the triangle shape
all timbers on the roof and along the cut face will all be different lengths stopping mass production

 

[woodblock13]

Thank you both - I will have a look at both options now!

@big-all do you mean laying a polystyrene block on top of the shed with the preset angle cut and then placing the rafters on top?

 

[Diver Fred]

Do you want a consistent fall (slope) on the roof or level eves?

 

[big-all]

make a perhaps 1/50th scale model so you can see the cut face rises and falls with the roof line from zero one end to perhaps 80% the other end
so if the roof starts at zero at the front and rises say 10" at the back for the slope
your cut face will vary by about 8" in hight side to side as its further back as it crosses as the roof rises

 

[freddiemercurystwin]

In your sketchup model, cast a line at the point where the studs meet the roof joists (red line), that will give you the height of the studs/wall panel all along the length of that wall. I built a similar shaped shed once, I built the walls as panels on the ground and fitted them together rather than built it all in-situ.

 

[woodblock13]

Do you want a consistent fall (slope) on the roof or level eves?

Level eves would be the priority - not fussed about a consistent roof fall, as long as it is tallest at the front left hand side.

 

[^woody^]

The top plate needs to be out of level to match the roof joists

 

[Notch7]

Level eves would be the priority - not fussed about a consistent roof fall, as long as it is tallest at the front left hand side.

If you want Level eves, the easiest way is to put your deck upstand at the back level, but the joists running into it so they slope.

If you truly want the eves level you will have to have a twisted flat roof - which I guess you could do with 11mm OSB, maybe 2 layers.


If I was doing a twisted flat roof, I would work out the shape of each joist and cut the fall accordingly.

It's quite easy - the height of the back and front is fixed, only the length varies.

So at one end you might have a fall of say 100mm over a length of say 600mm
At the other end the fall will still be 100mm but over a length of say 2100mm

Or do Level joists and add on firrings.

 

[^woody^]

The elevation with the door shows a slope at roof level, so why can't the side?

 

[Notch7]

The elevation with the door shows a slope at roof level, so why can't the side?

Yes Im struggling to see why not.

I would set the gutter level and have the roof slope towards the gutter.

Other 2 sides slope as they need to

 

[woodblock13]

If you want Level eves, the easiest way is to put your deck upstand at the back level, but the joists running into it so they slope.

If you truly want the eves level you will have to have a twisted flat roof - which I guess you could do with 11mm OSB, maybe 2 layers.


If I was doing a twisted flat roof, I would work out the shape of each joist and cut the fall accordingly.

It's quite easy - the height of the back and front is fixed, only the length varies.

So at one end you might have a fall of say 100mm over a length of say 600mm
At the other end the fall will still be 100mm but over a length of say 2100mm

Or do Level joists and add on firrings.

That sounds great, I'll have a look at both options (with and without firrings). Very helpful, thank you.