Needing some advice building a lean-to.

cjcocn · Apr 29, 2008

Chuck

Nice project. I will be building a new shed near my old barn (now my hunting shack) and will be building a similar lean-to in between the two buildings.

One question on your header that bridges the 14' gap on the front of your lean-to: have you made allowances for a stronger header on that side to adequately carry the weight of 14' of roof?

I am thinking of using 2x10s on that side and doubling them up to give me the added support. There will be a gap between the bottom of my header and the bottom of my 2x6 rafters, but I plan on nailing on a 2x4 to bridge the gap so that my rafters get a little more support (even though I will use those metal hangers as well).

I would draw you a picture, buy my skills in that area are really, really bad.

Chuck K. · Apr 30, 2008

cjcocn said:
Chuck

Nice project. I will be building a new shed near my old barn (now my hunting shack) and will be building a similar lean-to in between the two buildings.

One question on your header that bridges the 14' gap on the front of your lean-to: have you made allowances for a stronger header on that side to adequately carry the weight of 14' of roof?I am thinking of using 2x10s on that side and doubling them up to give me the added support. There will be a gap between the bottom of my header and the bottom of my 2x6 rafters, but I plan on nailing on a 2x4 to bridge the gap so that my rafters get a little more support (even though I will use those metal hangers as well).

I would draw you a picture, buy my skills in that area are really, really bad.

That is one thing I am still looking into. I have heard of making a beam using two boards with plywood in between, I believe some refer to it as a lamenated beam?.. I think 2 2"x10" would be a good starting point.. still looking for ideas..

MarkV · Apr 30, 2008

Chuck K. said:
That is one thing I am still looking into. I have heard of making a beam using two boards with plywood in between, I believe some refer to it as a lamenated beam?.. I think 2 2"x10" would be a good starting point.. still looking for ideas..

Chuck, a beam built with 1/2 ply in the center is pretty standard in house construction. The ply is added not so much for strength but to bring the beam width to 3½ inches which matchs a 2x4. That way it is the same width as the rest of a wall when put above a door or window as a header. In your case I would not consider it necessary.

You do need something larger than a 2x6 to span your 14 opening and carry the weight of the roof. Two 2x10's should be fine for the light weight roof you will install on the shed. An easy way to mount the beam is to set one 2x10 on each side of your vertical post and use carriage bolts drilled through. For your project the beam does not have to be one solid piece. On the back of the shed you should be able to use your 2x6's in the same manner with posts every 6'.

I was not clear on your plan for the roof itself. What you would normally see is rafters set on top of your beams and run from front to back. Six foot spacing would land the rafter on top of your back posts which would be very strong. To attach the metal roofing purlins, 2x4's laid on the flat, are run on top of and perpendicular to the rafters on 2' centers.

MarkV

EddieWalker · Apr 30, 2008

Chuck K. said:
I will soon be building a 12x'x24'x9' high (at lowest eve) lean-to ...

Is 4x6's on 6 centers adequate? I hope to get them ~3 in the ground.

Chuck,

The 4x6 posts are easily strong enough for 12 foot centers. What is important is the strength of your headers. At a 6 foot span, you won't have any issues with 2x6's doubled up. I always rip a sheet of half inch plywood and put it between my lumber when creating headers. The plywood eliminates the sag that might occur over time and brings the outside dimensions to 3 1/2 inches, or the same as a framing stud. Since you will have 4x6's, I'd notch the tops to support the load and tie the header and post together. I'd also add straps from the post, across the header and onto the rafters. This is extreme overkill for most builds, but code in parts of the country too.

Eddie

cjcocn · Apr 30, 2008

Eddie

What kind of straps should he (we) use? Do you have a pic you can post?

Also, I'm sure that you mean that the 4x6 post should be notched, but could you clarify? I am doing a similar build and it will be my first pole-built.

PS .... sorry to barge into your thread with these questions, Chuck, but I hope that the answers will benefit us both.

Thanks!

RobJ · Apr 30, 2008

You can also add some construction adhesive to the header Eddie mentioned for even more strenght. Key is a metal roof, much lighter.

But I'm still confused on which side is the "to" side? Does the 14' opening side open into an existing barn? I sort of like the open side concept. You are mostly protecting them from the weather, but you can still get at them easily.

Rob

RobJ · Apr 30, 2008

cjcocn said:
Eddie

What kind of straps should he (we) use? Do you have a pic you can post?

Also, I'm sure that you mean that the 4x6 post should be notched, but could you clarify? I am doing a similar build and it will be my first pole-built.

PS .... sorry to barge into your thread with these questions, Chuck, but I hope that the answers will benefit us both.

Thanks!

Just a metal strap you nail on is what I think he is talking about..a wind strap.

Here you can get teh idea..
http://www.ux1.eiu.edu/~cfrlw/T2k/Unit4/straps.gif
http://www.floridadisaster.org/mitigation/rcmp/HRG/images/structural/masonry_roof_to_wall_large.jpg

Here is a weak picture of a notch. See the guy has notched out both sides of the post (which is laying down). The headers will sit on top of the notch and will bear the downward weight. The other option is to butt nail it and it's just hanging by nails, or nail the header to the outside of the post, no can do with a 3-piece header. Or use a jack stud.

http://www.yankeebarnhomes.com/constructionguide/images/clip_image002_000.jpg

Jack stud..

http://www.architectionary.com/uploads/DoorFraming/doorframing.jpg

cjcocn · Apr 30, 2008

RobJ said:
Just a metal strap you nail on is what I think he is talking about..a wind strap.

Here you can get teh idea..
http://www.ux1.eiu.edu/~cfrlw/T2k/Unit4/straps.gif
http://www.floridadisaster.org/mitigation/rcmp/HRG/images/structural/masonry_roof_to_wall_large.jpg

Here is a weak picture of a notch. See the guy has notched out both sides of the post (which is laying down). The headers will sit on top of the notch and will bear the downward weight. The other option is to butt nail it and it's just hanging by nails, or nail the header to the outside of the post, no can do with a 3-piece header. Or use a jack stud.

http://www.yankeebarnhomes.com/constructionguide/images/clip_image002_000.jpg

Jack stud..

http://www.architectionary.com/uploads/DoorFraming/doorframing.jpg

RobJ

Thanks for the info. I am used to the jack/cripple/etc stud method, so every bit of info on pole-built helps!

EddieWalker · Apr 30, 2008

Rob covered it pretty good. Just go to the area in Home Depot or Lowes where they sell Simpson products. There will be all sorts of joist hangers, but if you look around, you will see a large variety of brackets and straps to make building stronger and easier.

A metal strap that goes down the length of a post, then across the header and ends in the rafter/truss will do mor to tie them all together then any other method. I still toe nail and if I'm not thrilled with the way my nails came out, I'll used 3 inch screws. Then after it's all together, I like to install a strap.

In the area of California where I'm from, it is code for the strap to start in the footing of the foundation and run in a continuos line up the wall and over the top of the rafter. This is for residential construction, but I forget the spacing of the straps for that. LOL

I wouldn't hang a header on the side of a post. Resting it on a jack stud would work as long as the jack stud was supported at the bottom by a footing of some kind. Never rely on a nail to suport anything. Nails are to hold things together, but not for loads.

The two options for the headers on top fo the posts are to either rest them across the top of the post and attach to the post into the end grain at the end. this us usually fine in most situations, but remember that fasteners into end grain are not as strong as through the side of wood.

The other option is to cut out the top part of the post so that the header rests on top of the post, but you can also fasten it to the side of the post that continues up the side of the header. Kind of like the letter "L" is removed from the top of the post. Does this make sense?

Eddie