French door in garden room

[Jupiter01]

The purpose of the lintel is to transfer the load to the ends. As long as the lintel supports the rafters and is positioned so that the ends are resting on a solid part of the wall that takes the load downwards (e.g. the post to which the door frame is attached) then it will be fine. It doesn't matter if it aligns with the front or back edge of the door, as long as it is supporting the ends of the rafters.

But since it’s a sloping flat roof, won’t the rafters only be touching the back of the lintel? If it’s pushed forward and their is a wooden fillet on the inside, I’m thinking that the load won’t be in the right place?

 

[mrrusty]

only be touching the back of the lintel?

birdsmouth or fillet! or if it's basically a flat roof, why not just keep the rafters level and use firrings?https://www.cwberry.com/47-x-47mm-timber-taper-pieces

 

[Jupiter01]

birdsmouth or fillet! or if it's basically a flat roof, why not just keep the rafters level and use firrings?https://www.cwberry.com/47-x-47mm-timber-taper-pieces

It’s rafters without birds mouth. The front wall will be 5cm higher than the rest

 

[mrrusty]

The front wall will be 5cm higher than the rest

You're overthinking it. Just let the rafters rest on the beam. They'll be fine...

 

[chirpychippy]

I might be missing your point but my originally proposed 5x2 (doubled) would be above the door and directly on top of this would be the roof joists

Ill try and explain this...with a drawing.

 

[Jupiter01]

Ill try and explain this...with a drawing.
View attachment 425399

Thanks for doing this. I now follow your suggestion. I can see how that would work. Presumably joist hangers would be needed at the back and front of that lintel as I have an overhang.

In the interim - and after a series of questions to chat gpt - I have purchased a 187cm SHS 70x70x5. I think this is plenty strong.

I’ve tried to draw this out on lined paper. Apologies!
This is what I had in mind. Please let me know your thoughts.

 

[mrrusty]

I can see what @chirpychippy is suggesting. The reason I was thinking joists over lintel is it gives you the opportunity to extend the joists over the doors. You will find that the bigger overhang you can build in the better. It will protect the doors from the weather.