Pole barn lean to

Slong1958 · Jan 16, 2020

I built a 24x40 pole barn awhile back now I want to add a lean to, but the pole barn is only 10ft tall and has a 12 over hang. The lean to I was thinking about you added another ledger board and went from there. I starting looking around on the web and saw this but Im not sure just what has to be done. The 1st is what I came across on the internet the other 2 are what I have. The problem with adding the lean to too my building as in my drawing is the height of the ceiling. The pic with the circle drawn around it looks like the rafter most be either sitting on the top ledger board or attached to it and that would rise everything up and would be ok. I think I know what has to be done but not sure. The 2nd pic is just something I put up to see how tall the roof would be.

EddieWalker · Jan 16, 2020

Cut off your rafter tails and install your 2x6's on top of the existing wall. Also attach them to the sides of your rafters.

How wide is your lean to going to be? Do you need to worry about snow sitting on top of it?

I said 2x6's in my first sentence, but that would be a minimum. Depending on your location and your span, bigger might be needed.

CADplans · Jan 16, 2020

Slong1958 said:
The problem with adding the lean to too my building as in my drawing is the height of the ceiling.

Can you lower the area of dirt that would be under the lean-to?
lower the floor, rather than raise the ceiling!! :thumbsup:

Slong1958 · Jan 16, 2020

Is this what your talking about as far as cutting the tresses and adding the rafters for the lean to. The lean to will be 12ft deep with a 24 in over hang the whole length of barn which will be 52 ft long when finished. The tin on the back will be moved to that wall leaving it open to the barn. Im also wanting to add another 12ft bay then enclose that 22x 36 and make it as dry as possible to house my vintage vehicles. Im going to remove the post that is circled yellow then add a 16 or 18 ft roll up door. This being a load bearing wall how big of a bean would I need?

ovrszd · Jan 16, 2020

As Eddie said, fasten to the side of your rafters rather than under.

Not sure about snow load in Tn.

Also not sure how far your lean to will extend?

ovrszd · Jan 16, 2020

Sorry, I was typing as you were.

I'll yield to Eddie for answers to your questions. Trust his word.

s219 · Jan 16, 2020

I went through this same decision process, in fact there is a thread here with some conversation:

https://www.tractorbynet.com/forums...-door-headroom-challenge-lean.html?highlight=

Here is what I ended up doing, work still in progress:

This was the best solution to get the headroom I wanted, however I estimate there was a 40-50% additional time penalty to knit the new roof into the old roof versus just going under the eave for the new roof (with a ledger board). Every step of the process was more complicated and took more time and introduced more "to-do" items that had to get done before the next step.

And of course before I could make forward progress I had to go backwards to tear off the old fascia/soffit, remove soffit blocking under the rafter tails, notch the wood siding to allow the new rafters to reach the header, cut back the gable soffit and fascia to the proper joint angle for the new trim, etc.... I have an asphalt roof, and weaving the new shingles into the old shingles at the transition also took a fair bit of work and preparation, and I put ice/water shield under that area since it is more prone to leaks right there.

So yes, I think it is the "right" approach to tie into the old roof, but be prepared for a lot more BS along the way. I feel like there is no shame in just going under the eave with the new roof attached to a ledger if you are looking for a more productive approach. I would have been done by now if I did that!

You can estimate how much more vertical space you'd gain/lose with each approach and make an informed decision. I gained about 7" of headroom by tying into the roof versus going under the eave, which made a critical difference in door height (slightly more than 7' versus well under 7').

BoylermanCT · Jan 16, 2020

I went the under the eaves route and put in a ledger board to attach the rafters to. I would also consider lowering the floor if you need more headroom.

Woody65 · Jan 16, 2020

Slapped this lean to together over the summer. Debated the same thing you are now and decided to take the easy way out and went under the existing soffit. Lack of extra help and disassembling everything along with cutting the steel roofing back to make a proper transition all played a part in the decision.