DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (
-   Building & Construction (
-   -   Hanging a small roof off of a wall? (

MushCreek 03-10-2013 11:29 AM

Hanging a small roof off of a wall?
I have big sliding doors on my barn, and I need to protect and weatherproof the hardware. Right now, if it rains with a good south wind, the water runs down the inside of my doors.

My plan is to build a small roof over the entire 24' of track, both to keep the rain out, and offer a little more protection against rain and sun when the doors are open. I was going to build small triangular trusses, then top them with purlins and tin roofing. The roof projects about 3-1/2' from the wall. The question is what is the best way to attach this to the wall? The wall is 2X6 studs on 16" centers. The bottom of the trusses can rest on the ledger that supports the door track; it is through-bolted through quad 2X12's that form the door header. Thoughts include lags, through-bolting through the studs, or cut slots in the siding and use nailing straps. I was thinking of making the trusses out of 4X4's, and having them on 4' centers, but that might put too much load on the studs they are attached to. Snow load here is only 10 psf. Here is a sketch:

woodworkbykirk 03-10-2013 11:36 AM

putting a small roof like that on is no big deal. the design needs a revamp though

joecaption 03-10-2013 02:32 PM

What type siding do you have now?
I feel you would need a ledger across the top to attach the rafters to.
The siding will need to be flash to keep it from leaking where the roofing meets the wall.

MushCreek 03-10-2013 06:53 PM

The siding is T1-11 plywood. I'm going to cut a slot at an upward angle to slide flashing up in to.

What do you mean by a design revamp? I was going to make the vertical member and rafter a 4X4, and the brace struts would be 2X4's on either side. Either that, or just all 2X4's with plywood gussets or nail plates. It's a triangle; as long as the corners are secured, it will be quite strong.

joecaption 03-10-2013 07:14 PM

Cuting the T111 at an angle like that and having it to close to the roof will just expose the end grain of the plywood and will be to close to the roof and splash back will rot out the siding.
I would cut away the siding, seal the bare exposed wood, add my flashing up the wall and out over the roofing, install Z moulding up under the Z molding then add 1 X 6 vinyl lumber.

Those 4 X 4's serve no real purpose.
A ledger at the top and bottom will do the same thing.

jagans 03-10-2013 08:44 PM

I have seen quite a few barn doors which simply have a Z metal flashing that counter flashes the top runner The top portion goes up under the siding above about three inches, then breaks outward at about 5 degrees for however far you need to clear the track by a couple inches, then down to cover your rollers, then a 1/2 inch kick with a return hem. You shold make this out of 22 gage stainless for strength. A small roof is not going to keep blowing rain off your doors, but the Z flashing will keep the water from behind them.

Just cutting a slot in the t1-11 dosent cut it. You have to remove a small portion so you can slide the flashing up behind the wall.

If you insist on the shed roof, you need a ledger board fastened to the studs horizontally and joist hangers to the ledger for your rafters. They come in various slopes for the purpose.

MushCreek 03-11-2013 05:17 AM

I'd really like to do the roof. A lot of times we get rain with a very slight breeze, allowing rain to come a foot or two into the open doors. The doorway is almost 12' high, so it's easy for the rain to come in. The barn has a 16" gable overhang, but it's 27' high!

I see what everybody means about a slot not being adequate. I had thought about removing a strip of siding so I could slide the flashing up behind it, then bend the flashing outward and replacing the cut out piece. I would carefully seal the cuts, and leave enough of a gap for a capillary break so moisture doesn't stay trapped there.

I see that the vertical member doesn't do much, as long as the rafter and strut are well attached to the studs. Then the studs serve as the vertical member. With the top ledger securing the rafter, and the strut braced against the bottom ledger, the shape locks in once the rafter is attached to the strut. I would think a lag screw would serve to attach the bottom of the strut. It does get loaded in an uplift situation.

hand drive 03-11-2013 07:31 AM

another way is to rip the siding at the height the bottom of the new rafter is and then up past where the top of the new rafter is say 6" to accommodate flashing after its built. if using 2x6's for rafters with a 6 pitch then figure 7" plus 6" = a 14" slot. Now slide the rafters up into the wall slot and scab next to pre existing studs of the barn wall and nail each rafter really good to each corresponding wall stud. fill in between rafters with 2x6 blocks ( kind of like a ledger except installed inside the wall) to eliminate pull out. you will also need to determine how far down the rafter to add the angled kick backs that go back down to the wall below the new roof and install them as you build it. Next, sheath new roof,shingle roof, flash roof to wall connection, put t 1-11siding back with z bar to interlock/seal the joint. your new roof effectively hangs off of the wall studs and is supported midway down the rafter span with the kickbacks. the barn wall may need some fortifying in the area that the rafters attach to and hang from it, stud to top plate connection etc....

a tip- build the end rafters first at the very edges and pull a string line across them to line up all the rest of the rafters. a trick I learned is instead of making the string line tight to the framing, hold the string line 1/8" to 1/4" away as you build and eyeball an 1/8" each time you use the string. this eliminates a stray rafter that bumps the string and throws the whole stringline off as you are building. a carpenter pencil is 1/4" and that is what I usually use as a gauge or eyeball :)

All times are GMT -5. The time now is 04:42 PM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

Search Engine Friendly URLs by vBSEO 3.6.1