Pitched roof over garage, wall plate on outer skin

mrbg07546

I am building a mono pitched roof over garage. The garage is double skin. But the garage door/lintel is only 4 inch. If I was to rest it against this it would mean the wall plate would have to be on the outer skin. Which means the wall plate is on the outer skin(and it usually needs to be on inner. ) would this pose a problem.

Gloomendoom

My house is single skin and about 400 years old. As far as I am aware, there are no problems with the wall plate.

leveller2911

mrbg07546 wrote: »

I am building a mono pitched roof over garage. The garage is double skin. But the garage door/lintel is only 4 inch. If I was to rest it against this it would mean the wall plate would have to be on the outer skin. Which means the wall plate is on the outer skin(and it usually needs to be on inner. ) would this pose a problem.

Its usual to have the lintel on the inside skin along with the wall plates for the roof to be pitched on. The outer skin of brickwork would usually be run up to so that it finishes under the soffit or infilled around the rafter feet. There is more chance of the wall plates,rafters etc rotting if they were on the outside skin.

If at al possible I would have the plates on the inside skin . Can you add a lintel to the inner skin across the door opening?.Not sure why there doesn't appear to be one fitted previously or is it a new garage?.

mrbg07546

Above the garage door you see a lintal

https://postimg.org/image/e11x984g5/

Furts

It is possible your current lintel is unsuitable for a wall plate both in terms of strength (that is a long span and that requires a substantial lintel) and shape (is it a Catnic/IG steel lintel which may not have a flat top). This will be subject to Buildings Regulations so you have to get it right.

Building a correct lintel on the inner leaf is childs play considering you are stripping back the existing roof and starting again, so why consider a non-orthodox approach?

From a technical perspective only you can answer a fundamental - often garages have a scimped foundation detail with for example, nothing between the opening piers, sometimes walls built off the slab, sometimes a raft type slab. They work as a garage but you have to be careful when building on upwards. The safe option would be to build off the inner leaf having checked out the foundation detail.