Roof pitch on an A-Frame with Bump-out Shed Dormer
![Roof pitch on an A-Frame with Bump-out Shed Dormer](https://i0.wp.com/www.projectsmallhouse.com/blog/wp-content/uploads/2020/06/featured-a-frame-bump.jpg?fit=810%2C431&ssl=1)
![1978 A-frame with a Bump Out Dormer](https://i0.wp.com/www.projectsmallhouse.com/blog/wp-content/uploads/2020/06/a-frame-1.jpg?resize=500%2C375&ssl=1)
This A-frame house is in our neighborhood.
![A-frame with shed roof bump out and bump out closet](https://i0.wp.com/www.projectsmallhouse.com/blog/wp-content/uploads/2020/06/a-frame-side-back.jpg?resize=500%2C375&ssl=1)
If this feels like a re-run, I wrote a short post about this last year. But we were on a different road and realized we can see the back of it here.
![Roof lines](https://i0.wp.com/www.projectsmallhouse.com/blog/wp-content/uploads/2020/06/a-frame-back-c.jpg?resize=500%2C375&ssl=1)
So this blog post is more about the roof lines and angles.
![Roof lines](https://i0.wp.com/www.projectsmallhouse.com/blog/wp-content/uploads/2020/06/a-frame-back-b.jpg?resize=500%2C375&ssl=1)
This view gives you a good idea of the roof lines.
![4/12 is a common roof pitch. 15/12 is very steep.](https://i0.wp.com/www.projectsmallhouse.com/blog/wp-content/uploads/2020/06/roof_pitch-1.jpg?resize=500%2C230&ssl=1)
It looks like the shed roof is a 4/12 pitch and the A-frame is 15/12.
![Roof lines](https://i0.wp.com/www.projectsmallhouse.com/blog/wp-content/uploads/2020/06/a-frame-shed_dormer-b.jpg?resize=500%2C375&ssl=1)
The slope ratio represents a certain amount of vertical rise for every 12 inches of horizontal run.
So a 4/12 roof pitch rises 4 inches for every 12 inches. The most common roof pitch is from 4/12 to 9/12.
The A-frame roof looks like a 15/12. That gives 51.34° angle.
![The higher roof line on the shed roof area adds a lot of usable space.](https://i0.wp.com/www.projectsmallhouse.com/blog/wp-content/uploads/2020/06/a-frame-back.jpg?resize=500%2C375&ssl=1)
An A-frame cuts off a lot of the height, so adding the shed roof area gives a lot more usable space.
![There is an additional bump out](https://i0.wp.com/www.projectsmallhouse.com/blog/wp-content/uploads/2020/06/a-frame-bump.jpg?resize=500%2C375&ssl=1)
There is also a bump out closet. They put in a garden window.
![The front of the A-frame is all windows](https://i0.wp.com/www.projectsmallhouse.com/blog/wp-content/uploads/2020/06/a-frame-windows.jpg?resize=500%2C375&ssl=1)
One problem with A-frame houses is that they can be dark inside. That is why they put so much glass on the walls that are not all roof.
![The shed dormer](https://i0.wp.com/www.projectsmallhouse.com/blog/wp-content/uploads/2020/06/a-frame-shed_dormer.jpg?resize=500%2C375&ssl=1)
This shows the back of the house better. There are not really a lot of windows on this side.
![There is an additional bump out](https://i0.wp.com/www.projectsmallhouse.com/blog/wp-content/uploads/2020/06/a-frame-bump_out_closet.jpg?resize=500%2C375&ssl=1)
Here is the closet bump out and the shed-roof bump out from the front.
![Garage](https://i0.wp.com/www.projectsmallhouse.com/blog/wp-content/uploads/2020/06/a-frame-garage.jpg?resize=500%2C375&ssl=1)
This is the garage. There are a lot of trees, so you can’t see it clearly.
![A-Frame Floor Plan](https://i0.wp.com/www.projectsmallhouse.com/blog/wp-content/uploads/2019/08/modified_a-frame-7.jpg?resize=500%2C440&ssl=1)
The floor plan is available on our county website. The closet bumps out 4′.