New Garage - Lean-To Design Question

[jeffdan17]

Good morning!

We are in the process of building a garage next to our house, and are looking to go ahead and build a lean-to on the back of it. The intended use of the lean-to will be to park our Kubota BX under, as well as store attachments, and any other small equipment we have. See attached photos for reference. The garage roof pitch is going to be a 4/12 pitch, matching the house roof as shown.
Sadly, I believe the dogwood has to go regardless. I am planning to remove the tree & stump, strip the topsoil, and install stone for the floor area. We will set the outer posts in concrete to get below the frostline.
We are struggling to envision which way to tie it into the garage, and what pitch to make the roof. I believe the options are to: 1. extend the roofline of the garage ahead out and keep the same pitch. 2. extend the roofline of the garage but change (flatten) the pitch for the lean-to. 3. tie into the garage just below the roof (into the siding). Looking for any and all suggestions!

 

[racecougar]

Yes, all three are options. What makes the most sense based upon your height requirements, aesthetic, etc.?

 

[CraigStu]

I wonder if you shouldn't actually increase the pitch some. Or drop the lean to attachment to the garage down to the top of the current osb and use the same pitch. It looks like 12ft walls plus 1-3ft of foundation above ground, so you could have a 20ft (?) lean to if you just extend the roof. This also depends on typical storm direction and whether you will have any wall on the outside of the lean to.

 

[jeffdan17]

I wonder if you shouldn't actually increase the pitch some. Or drop the lean to attachment to the garage down to the top of the current osb and use the same pitch. It looks like 12ft walls plus 1-3ft of foundation above ground, so you could have a 20ft (?) lean to if you just extend the roof. This also depends on typical storm direction and whether you will have any wall on the outside of the lean to.

Increasing the pitch could be an option as well, given the height, as you pointed out. For clarification, the walls are 10', and there's about 2' of foundation at the lowest point. As for typical storm direction, most of the time they are coming from the direction that the first 2 pictures were taken, meaning that wind/rain/snow could blow in at times. That being said, while we aren't planning on having any walls, we would probably want to keep the outer edge of the roof of the lean-to fairly low to keep as much of the elements out as possible. The Kubota BX would be the tallest piece of equipment we would store under it, and it's around 7' tall with the ROPS up, and around 5.5' with the ROPS down.

 

[jack stand]

Continuing the roofline with the lean to rafters bearing ON the wall just next to the trusses is the simplest in terms of framing if you have the vertical space for the lean to space rafters at the truss heel. If you don't already have your trusses, they can build them to accommodate your needs.

 

[LopezBart]

Given the slope away from the house, you may wish to configure the BX storage at the end furthest from the house so you can keep the ROPS up. I'd start the roof from a ledger board under the garage roof, but that's likely more due to style than anything else (e.g. option 3). Don't forget to run electrical there for battery maintainers, lights, etc.

 

[zimman]

So there are two windows on that side correct?
Zim

 

[jeffdan17]

So there are two windows on that side correct?
Zim

Hey Zim. Yes sir, two windows.

 

[jeffdan17]

Given the slope away from the house, you may wish to configure the BX storage at the end furthest from the house so you can keep the ROPS up. I'd start the roof from a ledger board under the garage roof, but that's likely more due to style than anything else (e.g. option 3). Don't forget to run electrical there for battery maintainers, lights, etc.

That is exactly what I have in mind for the BX storage, with the implements stored on the end closest to the house. Thanks for the input on where to tie-in!

 

[jeffdan17]

Continuing the roofline with the lean to rafters bearing ON the wall just next to the trusses is the simplest in terms of framing if you have the vertical space for the lean to space rafters at the truss heel. If you don't already have your trusses, they can build them to accommodate your needs.

Thanks for the input! We do already have the trusses, and are beginning to set them today.

 

[zimman]

Not to scale, not proportional and not very good you get the idea.
Zim

 

[jeffdan17]

Not to scale, not proportional and not very good you get the idea.
Zim

Awesome sketch! The trusses are actually running the other way though, same direction as the house's. That's the main thing that I'm trying to decide on: do we tie the lean-to onto the end of the garage trusses, or tie into the siding just beneath the trusses?

 

[zimman]

Awesome sketch! The trusses are actually running the other way though, same direction as the house's. That's the main thing that I'm trying to decide on: do we tie the lean-to onto the end of the garage trusses, or tie into the siding just beneath the trusses?

No I'd just run a 2x12 or 2x10 across the back of the garage and then drop your rafters from that. Without seeing the trusses I'd have a hard time sketching it but because of the height of the roofline I would drop it down a bit. Unless you're parking a RV under it. LOL
Zim

 

[jeffdan17]

No I'd just run a 2x12 or 2x10 across the back of the garage and then drop your rafters from that. Without seeing the trusses I'd have a hard time sketching it but because of the height of the roofline I would drop it down a bit. Unless you're parking a RV under it. LOL
Zim

LOL. Definitely no RV's. Thanks for the input, and for the sketch!

 

[Youngandfree]

I'd basically sister the lean too rafters to the sides of the trusses so that the roof line is continuous. Have the rafters bearing on the top plate next to the trusses. Like the sketch above but just raise the rafters up to the top of the side wall.

 

[CraigStu]

I like zinman's 2nd sketch. W/ the BX only needing 7ft, I'd figure the outer edge of the roof at 6.5ft just so you can walk under it w/o hitting your head. Kind of working backwards from that, match the main roof pitch, and attach the ledger where ever that dictates. Typing this and thinking at the same time, if you don't want to wall the outside, maybe get the ledger just a foot down from the existing overhang, whatever clearance you need to be able to flash the joint. Then go for a pretty wide lean to (whatever the pitch gets you starting from the wall) so rain and wind can blow in but still miss the BX.

 

[jeffdan17]

I like zinman's 2nd sketch. W/ the BX only needing 7ft, I'd figure the outer edge of the roof at 6.5ft just so you can walk under it w/o hitting your head. Kind of working backwards from that, match the main roof pitch, and attach the ledger where ever that dictates. Typing this and thinking at the same time, if you don't want to wall the outside, maybe get the ledger just a foot down from the existing overhang, whatever clearance you need to be able to flash the joint. Then go for a pretty wide lean to (whatever the pitch gets you starting from the wall) so rain and wind can blow in but still miss the BX.

You have basically hit the nail on the head with what we’ve decided to do, except it will be 7’ at the lowest point!

 

[TimberMan]

Jumping in a little late here but I am finishing my barn build with lean to as I type. My lean to has the same intended purpose as yours and my only advice is to go as high as you can tolerate esthetically. You want l be able to get in there with an implement hanging from rigging straps, attached to your loader and ideally, you will want to have 3-side access with your tractor with the roll bar up.

Your sketch looks great BTW.

 

[TimberMan]

Also, I used the top plate of the barn wall to support the lean-to roof and the main roof rafters which eliminated the ledger board and brought the roof up a bit higher.

 

[Codyboy]

I tied the lean-to rafters right to the top plate of the building. That gave me full height and the roof tied together nicely. The roof on the building is 4/12 the lean-to i think I set it at 1.5/12.
But my roof is metal , not sure what your using.

 

[BobnCO]

Two separate roofs tends to look nicer architecturally to me!

 

[Jackfre]

I think setting this up for the BX as the tallest piece ties your hands for future developments/needs. If you are going to the expense of putting a roof up I’d try to keep the outside walls at least 8’. The BX’s are compact for sure, but implements and supporting gear need space to safely navigate the in, out, up, down of storage and handling. I’d tie the shed rafters into the new rafters and make the new wall as high as possible. Yes, that will alter your roof line but it will give you the most space. I believe that it will take no time at all for the shed roof to get walls too. A shed roof keeps the vertical rain/snow off the machine but you say you are on the weather side as is. You will have to enclose it to use the space. I have to kind of chuckle as I’m writing this as I have a lot of experience of re-modeling the new building while it is going up. The other thing you are missing is that while the BX’s are great, I had a 23 & 2660, making the space small means you can’t move up to a B or larger and you know you want a bigger tractor That’s the way tractors are.

 

[CraigStu]

Don't forget that OP will have the garage wall at 10ft plus there is 2ft of foundation so top of wall is approx 12ft off the ground. So even dropping the lean to down a foot or so to allow flashing under the garage roof overhang, he still can have a lean to that starts at 10.5 ft clearance or so depending on the size of the roof joists. He will have plenty of vertical room against the garage wall for a larger tractor.

 

[TimberMan]

Don't forget that OP will have the garage wall at 10ft plus there is 2ft of foundation so top of wall is approx 12ft off the ground. So even dropping the lean to down a foot or so to allow flashing under the garage roof overhang, he still can have a lean to that starts at 10.5 ft clearance or so depending on the size of the roof joists. He will have plenty of vertical room against the garage wall for a larger tractor.

Don’t forget about the beam depth supporting the tail end of the rafters.

 

[tealetm]

Thought I'd attached a few photos of my barn with the lean-to as I designed it. Just for reference.

 

[CraigStu]

We happened to have some wrapping paper that has 1" squares on the back side to help w/ cutting it correctly. I have used this to layout different things using 1' = 1' and one larger project 1" = 1yd. I bet this could help you make a decision as to your lean to roof.

 

[jeffdan17]

Update on the lean-to:

We still have some small things to tidy up, but the garage and lean-to are up and finished! We ended up not following the same pitch as the roof or tying the lean-to into the trusses. The tie-in point ended up about 1’ down from the top of the garage wall, giving it around a 2/1 pitch. The shortest point has about 7-1/2’ of clearance, fitting the BX under it comfortably.

Very happy with how it turned out! Thanks to all for the suggestions and conversation!

 

[finn]

I'd basically sister the lean too rafters to the sides of the trusses so that the roof line is continuous. Have the rafters bearing on the top plate next to the trusses. Like the sketch above but just raise the rafters up to the top of the side wall.

That’s how mine was built. Snow slides all the way down the continuous roof pitch and drops off the eave.

My friend had a non continuous lean to roof that started a couple of feet below the main eave. Snow melt / ice would slide down the upper roof and puncture the lower roof. Steel roof.

 

[BobnCO]

Looks good! And finctional.

 

[CraigStu]

Nicely done!