Lean to options for new garage

[kdrymer]

Looking at adding a lean-to to a new stick-built garage build I am still planning on Northeastern Pennsylvania. The garage will be 28x32 (with gables on 28' side) with 10 foot tall walls and 9/12 trusses for additional attic storage. I am looking at building on a monolithic slab. I am looking at also having a lean to built on the 32' side (either the entire length or half of it depending on additional costs). The lean to would be either 6 or 8 feet wide.

I'm not quite sure how best to attach the lean to to the structure. It looks like there are two options, either attach to a ledger board in the garage wall with the rafters running underneath the truss overhang, or I'm wondering if there's a way to attach over the top of the top wall-plate and have the main roof continue at a lower pitch. This way the end of the rafter is supported by the garage wall and not the truss and the facia is continuous, but I realize theres probably something obvious I'm not considering with this.

I've attached a sample picture showing the first option, but I'm just not crazy about the two separate roof sections and want to know other possible options. I'd prefer the lean to doesnt look like an after-thought and blends with the existing building.

 

[jack stand]

Nothing wrong with your leanto attachment! It saves you dealing with an additional eave to build and trim out. It will also shed snow better than it dropping onto the lower roof. I'd suggest a metal roof.
I would put the money from any "attic" storage into another leanto for the opposite wall.
To me, with the stairs taking up valuable space from both floors and the tendency of them just storing stuff that you (I) should just get rid of. But this is me!.
It's easy to put in some headers in your stick framed wall to provide access to the lento area from the main floor effectively increasing the main floor s/f and don't forget the 100+ s/f that the stairway will eat up between the two floors.

 

[kdrymer]

Nothing wrong with your leanto attachment! It saves you dealing with an additional eave to build and trim out. It will also shed snow better than it dropping onto the lower roof. I'd suggest a metal roof.
I would put the money from any "attic" storage into another leanto for the opposite wall.
To me, with the stairs taking up valuable space from both floors and the tendency of them just storing stuff that you (I) should just get rid of. But this is me!.
It's easy to put in some headers in your stick framed wall to provide access to the lento area from the main floor effectively increasing the main floor s/f and don't forget the 100+ s/f that the stairway will eat up between the two floors.

Thanks for the feedback. Just to be clear, are you saying what I described with having the rafters bearing on the wall plate is feasible, as opposed to the example picture I attached that uses a ledger board and separate roof?

I've seen some suggestions about having the main structure's roof trusses be a raised heel truss to allow clearance for a rafter to be placed along side of it over the wall plate.

 

[jblnut]

Not sure what this design is called but my rafters sit on a header board that is attached to my verticals support poles. The lean to “rafters” which are 18’ 2x10’s are attached to the rafter tail and sit on the same header board as the shed rafter. One continuous roof up top. Plywood in between the rafters to close the gap so insulation doesn’t fall out into the leanto and Bobs your uncle.

 

[Codyboy]

Not sure what this design is called but my rafters sit on a header board that is attached to my verticals support poles. The lean to “rafters” which are 18’ 2x10’s are attached to the rafter tail and sit on the same header board as the shed rafter. One continuous roof up top. Plywood in between the rafters to close the gap so insulation doesn’t fall out into the leanto and Bobs your uncle.

Wasn't trying to quote.
Anyway I built mine like this. Lean to rafters sit on the top plate right next to the trusses.

 

[u2slow]

My dual lean-to's are integral with the pimary roof line. Its actually one massive truss the whole way across.

 

[larry4406]

Here are some pictures of our barn build. The main area is trusses at 9/12 while the "lean to" portion was field framed with 2x10 rafters and then 2x6's for a ceiling. I don't recall the shed roof pitch, perhaps 3/12?

The 2x10 rafters align with the roof, then vertical supports are added below it to post down onto the wall.

For scale, the structure is 26' wide and 24' deep.

I did it this way as the trusses were free rejects from the day job. The truss span was actually not quite right for me, so I first installed 2x10's then stacked the truss on it. The enclosed barn section is 13' wide.

I would do as @u2slow suggests and have it made integral to the main truss since you are a new build.

 

[CraigStu]

Another option might be to have your trusses designed to form the lean to roof. I am not sure if the 9/12 pitch would work w/o making the outer roof edge too low though. Ooops u2slow beat me to it.

 

[jack stand]

Thanks for the feedback. Just to be clear, are you saying what I described with having the rafters bearing on the wall plate is feasible, as opposed to the example picture I attached that uses a ledger board and separate roof?

I've seen some suggestions about having the main structure's roof trusses be a raised heel truss to allow clearance for a rafter to be placed along side of it over the wall plate.

Yes, you'll have to cut a correct birds mouth at the bearing point on the wall plate.
I'm confused if you're using rafters or "attic trusses" for the main roof?
Do you envision the same pitch for both the main and leanto roof?

 

[finn]

My 16’x50’ lean to was constructed after the fact. There’s a mono slope roofline, presumably to help snow shedding. No contractors I talked to would willingly recommend an interrupted pitch roof for that reason, although I know they’re popular in mild climates. A friend added a metal roof to replace the shingles on his old mining era house. There was a couple foot drop between the main roof and the “shed roof” over the kitchen.

You guessed it… ice fell off the upper roof and punctured the shed roof over the kitchen,

My original structure was stick built, using trusses. The lean to uses posts on the outside wall, with bird mouth rafters sitting on the existing top plate. The rafters follow the original pitch, and I presume simple geometry defined actual room width.

0ne contractor, if I understood correctly, stated that the new at the time building inspector was putting up resistance at using different construction techniques in the same building. Ie monolithic slab for the main building and buried posts on a concrete pill for an attached lean to.

 

[jblnut]

Looking up at shop side. It was recently enclosed. Before it was there would be snow sitting on literally everything. That’s a big part of why all the wood is discolored and why I finally enclosed it.


Looking up at outside wall side.

 

[TurnipTruck]

A lean-to that is only 6 or 8 feet wide is not for parking. What do you plan to use it for? At only 6’, you may be able to just order trusses that cantilever that far without posts. Eight feet is possible but pushing it, depending upon hurricanes or snow load. Four foot is sufficient for firewood or a canoe or maybe even a fourwheeler. Ten foot is the minimum for cars and trucks, twelve is better for trailers.
My rafters are birdsmouthed at each end and sit on top of the walls and sistered to the roof trusses:

I cut in an additional birdsmouth for a ledger board at the top of the wall but it seems it has been fine without the extra overkill.



I continued the 4/12 shop roof pitch on to the lean-to primarily for snow shedding, but avoiding leaks at a flashed pitch change and avoiding the extra cost of additional fascia is not without merit.

 

[finn]

I think my 16’ wide lean to is a little narrow. I can’t see going less than that.