Skillion roof end support

[Mark22]

I am building a 5m x 3m room off an existing weatherboard house. The extension will have a skillion sheet roof with low pitch attached to the house along the 5m edge. Construction is pine frame, weatherboard on concrete stumps. How are the 3m rafters(120x45f17) fixed to the house if the existing house wall is used for one side of the room? The wall is made of 90x45 pine studs. The wall is without eaves and the rafters will attach about 200mm below the top plate.

I was thinking of a lintel across the length, birdmouthing rafters to sit on lintel at house end and on opposite top plate on extension. Is this the best/correct way to do this, and do the Aust standards specify lintel dimensions for supporting rafters?
Thanks in anticipation!
Mark

[jatt]

If it was me extend the rafters into the wall cavity of the existing bit. Use a beam (lintel) below, tripple grip the 2 together.

Block below and nail to existing studs. If u have any doubts about the studs, seriously entertain laminating another stud that picks up the underside of the rafter to the bottom plate.

My place uses premade trusses, but the principles i followed arentmuch different. the inspector was a bit anal, but it passed.

Seen coach bolts being used to attach rafters to existing studs, which to me seems reasonable, but may not be up 2 current standards.

[Mark22]

Thanks Jatt
With your suggestion for the studs laminated to existing studs, would these stop under the lintel and extend to the bottom plate, or cut out so they extend to top of lintel and rafters sit on this stud and lintel?
Cheers Mark

[jatt]

Now I'm not a builder.

This drawing may help expain the approach I used. Unfortunately arent on site at present to take a foto.

red line shows bottom plate, black is existing stud, yellow is a a piece laminated to stud, blue is rafter of extension, grey is a laminated piece.

The blocking/laminated piece sits directly under the rafter in the wall cavity.

Now I was able to hide the lintle as it is in the ceiling cavity created by trusses. My span was 6 mtr compared to only 3 in your case, so a lintel may not be required, however if it is done away with I would definetely run a complete stud to the ground.

With a lintle in place It may be enough to shoot some decent blocks under your rafters instead of running them all the way to the ground.

Any openings between the two areas may need some special attention. Fotos always are the go.