Shed roof

[Jupiter01]

I am in the process of building a small lean to shed. It’s around 5 metres long but only 50cm wide.

I have a 45 x 95 timber that I was going to bolt to the house wall and hang my rafters off here. Again, since the span is only around 50cm (plus some overhang), I am using 63mm cls for my rafters. It will hold an 18mm OSB board and then have a rubber roof on this.

As seen in the annotated image, the horizontal line is the top of the wall timber (for rafters) and the vertical lines are the sides of the shed. There is approximately a metre where I won’t be able to fit the wall plate (due to slanting soil pipe) and wondering how I handle the roof rafters for this. As you can see, I can then fit a new section of the wall timber to the right of this proper and continues with the rafters. I would appreciate your advice on this.

I am using rubber boots for all the pipes going into the rubber roof.

Thanks in advance.

 

[DAZB]

I would take the pipes out of the equation and elbow them as soon as you can after exiting the house and run them to the stack above your proposed wall plate. You then only have the main soil pipe to get around and you can fit wall plate to within an inch of it and the rafters can then be spaced either side of it with a trimmer in front of it.

 

[Jupiter01]

I would take the pipes out of the equation and elbow them as soon as you can after exiting the house and run them to the stack above your proposed wall plate. You then only have the main soil pipe to get around and you can fit wall plate to within an inch of it and the rafters can then be spaced either side of it with a trimmer in front of it.

I did consider altering the pipes but really don’t want to get into that. It’s a dirty job. Literally!
Can’t I put in trimmers across the 1m span? A bit like you would when putting in a velux. It’s not a big roof so won’t be heavy.

 

[DAZB]

Yes that can be done and based on the fact it is a narrow roof with minimum weight just double up the rafters both sides and the head trimmer in front of the pipe.

 

[Jupiter01]

Thanks for your help with this @DAZB. Much appreciated.
I had a couple of related points I wanted to get your advice on please:

1) When I cut the OSB to slot in the various pipes. I can use my jigsaw to have a round half at the top of this cut but the OSB behind this will also need to be removed so I can slide this in place. How should I fit the OSB into the section behind the pipe afterwards as this will need to be secure enough to lay the rubber roof?

2) I am using 63mm CLS for the roof rafters, given the size of this. I will cut the top end at the appropriate angle so it is flush to the timber bolted against the wall and then screw this in. On the other end of the rafter, I want to avoid a mouthcut as I've not done it and it probably isn't warranted for this situation. Can I instead use trimmers and screw the joists to the timber it is resting on? Also, when the OSB board gets screwed in, it should give it more rigidity and strength.

I would appreciate your thoughts on the above please. Thanks again.

 

[DAZB]

1) You would be able to slip the piece you need in behind the pipe and either screw/nail it if you can or use a good glue/adhesive and it will be fine for the rubber roof to cover over.
2) trimmers will work fine here and more than adequate in your situation.
I would use 18mm OSB and space your rafters at 400mm if you will ever need to walk on it or max 600mm if not.

 

[Jupiter01]

By default, I would have a single CLS running across all the vertical studs. In this case, given that the rafters will be resting on this along with the OSB Board and the rubber, should I be doubling-up on this horizontal CLS timber?