NJank
07-08-2008, 01:17 PM
Ok, putting up a covered porch on the front of our split level (single story side) and I had a few roof questions. Planning a shed roof on a 10.5x21ft porch, tied back into the existing roof. Since I've never roofed a deck before, I have a couple basic design questions followed by a request for advice.
First, two pictures attached. (1) front yard top-down layout with porch. (2) Quick-porch layout a la Lowes to save you from my hand sketch.
The slight 'tweak' comes from an existing curved concrete walkway/steps to the driveway. I wanted to make use of this walkway as-is, and drop the steps right on top of them at a 45degree angle from a corner of the porch. The setback limits (to frame, steps don't count) prevent us from bringing out the porch far enough to have the stairs come out the side and drop onto the walk after the curve (~13ft), and my wife complained about shortening the porch (to ~7ft) so that they could go straight out the front as a neighbor had done a couple years back. So, the compromise was ~10-1/2 feet, a ~3.5ft 45degree corner lopped off, and stairs that drop right on the walkway. Yes. I'm that lazy about the concrete work for rerouting the walkway.
So, now, does my shed roof have to change significantly because of this missing corner? The end ceiling joist would cantilever over the stair notch by 2.5-3 feet. I assume I'd need to truss that end to better transfer weight to the post.
Next, would you do something other than a shed roof? Or, at least, something different at that corner. (for a shed, I couldn't think of anything different there.) I don't have the rise/run of my current roof right now, but our code minimum is 4/12, and my estimate for the main house would be something like 6 to 7. (that side of the roof has ~13-14ft run, so 6-7ft high)
Second question regards roof posts relative to deck posts. My wife would like decorative posts instead of extending the deck posts up to the roof beam. Is it crucial that the roof posts be over the deck posts? As long as they're over a beam, whats the post/post offset limit? For a shed roof, would that just be on the front under the roof beam as opposed to the sides under the joist? Looking at the quickie Lowes post layout, I realize I likely couldn't use that as-is due to the side cantilver.
My county has a nice code summary for decks, but no specs on the roof other than 2006 IRC. Before I head to the library to read that, are there any easy pointers or online references?
I'm planning on doing the porch myself, putting in some of the roof support/framing (maybe just stopping after the posts, maybe doing some of the roof frame. depends on complexity) and then contracting the rest. So, I'm mainly concerned about doing the deck in a way that won't make the rest of the job a bear. Of course, my stubbornness about the walk could have already shot that in the foot.
thoughts?
First, two pictures attached. (1) front yard top-down layout with porch. (2) Quick-porch layout a la Lowes to save you from my hand sketch.
The slight 'tweak' comes from an existing curved concrete walkway/steps to the driveway. I wanted to make use of this walkway as-is, and drop the steps right on top of them at a 45degree angle from a corner of the porch. The setback limits (to frame, steps don't count) prevent us from bringing out the porch far enough to have the stairs come out the side and drop onto the walk after the curve (~13ft), and my wife complained about shortening the porch (to ~7ft) so that they could go straight out the front as a neighbor had done a couple years back. So, the compromise was ~10-1/2 feet, a ~3.5ft 45degree corner lopped off, and stairs that drop right on the walkway. Yes. I'm that lazy about the concrete work for rerouting the walkway.
So, now, does my shed roof have to change significantly because of this missing corner? The end ceiling joist would cantilever over the stair notch by 2.5-3 feet. I assume I'd need to truss that end to better transfer weight to the post.
Next, would you do something other than a shed roof? Or, at least, something different at that corner. (for a shed, I couldn't think of anything different there.) I don't have the rise/run of my current roof right now, but our code minimum is 4/12, and my estimate for the main house would be something like 6 to 7. (that side of the roof has ~13-14ft run, so 6-7ft high)
Second question regards roof posts relative to deck posts. My wife would like decorative posts instead of extending the deck posts up to the roof beam. Is it crucial that the roof posts be over the deck posts? As long as they're over a beam, whats the post/post offset limit? For a shed roof, would that just be on the front under the roof beam as opposed to the sides under the joist? Looking at the quickie Lowes post layout, I realize I likely couldn't use that as-is due to the side cantilver.
My county has a nice code summary for decks, but no specs on the roof other than 2006 IRC. Before I head to the library to read that, are there any easy pointers or online references?
I'm planning on doing the porch myself, putting in some of the roof support/framing (maybe just stopping after the posts, maybe doing some of the roof frame. depends on complexity) and then contracting the rest. So, I'm mainly concerned about doing the deck in a way that won't make the rest of the job a bear. Of course, my stubbornness about the walk could have already shot that in the foot.
thoughts?