20x34 2-story universal in upstate NY

Started by NathanS, May 13, 2016, 11:04:09 AM

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jsahara24

Quote from: NathanS on August 18, 2016, 03:05:31 PM
We are in 50psf snow load with the typical wind design speeds. Going either 9-12 or 10-12 with standing seam panels, likely no exposed fasteners. Would require some really strange conditions for snow to not quickly fall off the roof.

I've been following your thread and you've done a great job!  In regards to your comment above, I see you're from upstate NY, I have a cabin in the tug hill area and two winters ago it didn't go above freezing for the entire month of February and the snow piled up on the roof.  I had about 3' or more compressed snow on the roof and it didn't shed it until it warmed up in early march.   I have a metal roof with exposed screws, 9:12 pitch, 2' overhang on the eave and 18" on the gable.  This isn't normal, but you never know. 

Good luck on the build, keep the pictures coming!
Jason

NathanS

#76
Quote from: ChugiakTinkerer on August 18, 2016, 06:49:10 PM

For the IRC, which I am going by, the 24" for eave overhang is measured from horizontal, not slope distance.  Your code may be the same, it's worth double-checking.

You are right about the 24" on the eave measured horizontally (from 804.3.2.1.1). But this diagram from 802.7.1.1 is either drawn wrong or the code is just contradicting itself.

edit; ive been reading this some more and I think the 12" rake overhang from 804.3.2.1.1 is actually for steel framing. Sometimes I search pages for key words because the sections are so big. maybe for nominal lumber the permitted cantilever is 24" at the rake too.



NathanS

Quote from: jsahara24 on August 18, 2016, 08:31:27 PM
I've been following your thread and you've done a great job!  In regards to your comment above, I see you're from upstate NY, I have a cabin in the tug hill area and two winters ago it didn't go above freezing for the entire month of February and the snow piled up on the roof.  I had about 3' or more compressed snow on the roof and it didn't shed it until it warmed up in early march.   I have a metal roof with exposed screws, 9:12 pitch, 2' overhang on the eave and 18" on the gable.  This isn't normal, but you never know. 

Good luck on the build, keep the pictures coming!
Jason

Thanks Jason I appreciate it. That winter I remember some areas the snow drifts were taller than my truck. We get a little lake effect down in Chenango but it is nothing like up your way. Even Hamilton gets a lot more snow than us. I am ready for some cooler weather, the heat and humidity this summer has really started slow me down. It is hard to work a full day.

Is your gable framed the way Don suggested? You make a good point, whatever I do I should not expect the snow to shed itself off.

Don_P

Whoa, 5 replies while I was noodling around, well, one more  ;D

If you have gutters or vents, etc in the lower portion of the roof sliding snow can be an issue. Very often I hear the argument that the roof will self clear, then they realize they need to keep the snow up there, so think that through. Strange conditions only need to happen once, I've had 3' of snow stick to one of mine at 12/12 with exposed screws.

For the rake overhang check the WFCM pg 65 table 2.2C. It is an uplift table but is for 2'.
I'd skip a rafter and go 2 bays inboard. You can furr down the underside if it is cathedral. Pg 174&175, same tables in the prescriptive section, again set up for 2' rake overhangs. Can you give me a cite for the 1', I don't recall that.

At the eaves... I have serious problems with the entirety of IRC 802.7 and did my best. AWC's engineer and I went a couple of rounds starting in person and continuing by email before he shucked me off on an intern. An engineering professor did not disagree with me. This is a bearing similar to the cut end of a stud, not a notch and the 2' limit is arbitrary. They have a thinking problem IMO and have yet to explain their thinking adequately. Now that I've vented  ::), the inspector has to follow the rules. Work around, bobtail rafters with scabbed on cantilevered tails, 2/3 in 1/3 out... clear it with inspections first but I've done this as an engineered detail several times when exceeding stock lengths. If you box out a level soffit to form a rigid triangle their argument starts to become absurd. I am not your inspector though, clear anything that is outside of prescriptive.

Don't forget to block the seams on your wall sheathing before you zip tape. I've been blocking it seems like forever, sheathing, wainscot throughout needed it and for grab and towel bars in the baths. I need to talk to the cabinetmaker about his needs as well. I love blocking  :P 

Redoverfarm

Nathan if you go with exposed fasteners on your metal might I suggest what I used on mine.  They are pan head with the torx inset in the head.  They are less prone to collect what ever needs to slide off the roof like hex headed screws.  They come in colors the same as regular fasteners.



In addition I used a ice/snow guard ( Witches Hat )to prevent the gutter from being torn off by sliding snow.  It still allows melting snow and water to exit the roof. 







NathanS

#80
Thanks for the great info Don. I was wrong about the 12" rake - I was accidentally looking at the steel framing section. It looks like the code book is pretty silent on rake overhang for lumber. The codes have been getting the best of me on some of these details lately.

Relieved to see provisions for a 2' rake overhang. (in WFCM manual, which is approved by code in section 3 for anyone reading)

If my brain is working right this time, it looks like they're saying the max overhang length of the outlooker is half the total outlooker length. So If I want to overhang 24" my 16" OC rafters get in the way a little bit. If I step the first one back 24" I am still within the code because the 2x10s rafters actually are rated to span 11' 3" @ 24" OC. I could still double that rafter up to give it a little extra strength.

Don If I skip the first rafter and span 32" inboard are there code provisions for this? Hard to imagine anything wrong with that if I double up the rafter. Also seems like this follows cantilever rules better.

Also thanks for the reminder on blocking all the gaps in the sheathing. I don't think I have seen that in the code either. I know that it's a big deal in California to do that, but thought out east we didnt need to block everything.

I am glad I am doing a relatively simple build. It is funny that switching from 24 OC rafters to 16 OC rafters has implications on overhangs. You just don't know what you don't know. Although I do know there is a lot I don't know.  ;D

NathanS

Quote from: Redoverfarm on August 19, 2016, 06:32:37 AM
Nathan if you go with exposed fasteners on your metal might I suggest what I used on mine.  They are pan head with the torx inset in the head.  They are less prone to collect what ever needs to slide off the roof like hex headed screws.  They come in colors the same as regular fasteners.


Thanks Red. Since I ordered a standing seam roof, they come in 16" sections. One side gets pancake screws, and then the other side snaps in overtop - leaving nothing exposed. When I ordered the roof, I thought I was going to have exposed fasteners at the eave edge and at the rakes. But, I was just looking at the order the other day, and it looks like they are sending me the stuff to do it with no exposed fasteners. THis means the gable trim gets pop rivets, and the panels at the eaves actually have the bottom 1" of the panel bent 180 degrees and tucked underneath a flange.

I like those screws you showed more than the hex screws (used on my shed). Do they have a rubber washer on them?

Side note, I was so surprised by how inexpensive the roof was. this is for the 34x20 + 8x12 mudroom. The quote for the standard panels was $1800 and for standing seam we paid around $2800. That includes all the trim and even the fasteners. ABC roof has a branch in Utica.

Redoverfarm

Quote from: NathanS on August 19, 2016, 06:47:02 AM

I like those screws you showed more than the hex screws (used on my shed). Do they have a rubber washer on them?


Yes they are identical in thread and gasket like hex head.  They have proved themselves being close to the woods with pine needles and leaves wanting to hang up.

Don_P

Data dump  :D ( you know, the entire codebook was about the size of the wall bracing section when I started. I can't imagine trying to grasp it coming into it now. Large sections of it have slipped from my ken. I'm not sure the level of detail has helped)

QuoteIf I skip the first rafter and span 32" inboard are there code provisions for this? Hard to imagine anything wrong with that if I double up the rafter. Also seems like this follows cantilever rules better.
Nothing called out that I can recall, but if you space wider than 24 you're off the span tables, a double there would get you back to the intent.

R602.10.3
QuoteOnly braced wall panels parallel to the braced wall line shall contribute toward the required length of bracing of that braced wall line. Braced wall panels along an angled wall meeting the minimum length requirements of Tables R602.10.5 and R602.10.5.2 shall be permitted to contribute its projected length toward the minimum required length of bracing for the braced wall line as shown in Figure R602.10.1.4. Any braced wall panel on an angled wall at the end of a braced wall line shall contribute its projected length for only one of the braced wall lines at the projected corner

See R602.10.7 case 5 for braced wall end conditions for the balcony... I called out 12' the other day, it's 10'

I'm looking for blocking requirements in the footnotes, not finding it, I think technically you are correct, it is not required... its a good idea, greatly improves shear and keeps the edges flat over the long haul. Aside, do not glue wall sheathing. It reduces ductility and transfers too much lateral to other connections. The prohibition is for seismic but generally not a good idea.


jsahara24

Quote from: NathanS on August 18, 2016, 08:40:48 PM
Thanks Jason I appreciate it. That winter I remember some areas the snow drifts were taller than my truck. We get a little lake effect down in Chenango but it is nothing like up your way. Even Hamilton gets a lot more snow than us. I am ready for some cooler weather, the heat and humidity this summer has really started slow me down. It is hard to work a full day.

Is your gable framed the way Don suggested? You make a good point, whatever I do I should not expect the snow to shed itself off.

I framed my gable with purlins every 2' up the roof hanging over 18".  then I tied in my fascia board and put short 2x8s every 16" between the last rafter and the fly rafter.   Has been holding up the last 3 winters.   

I've never seem so much snow as up in the tug hill area, deepest I've had it was abiut 42"-48" without drifts.  Think you gotta head out west to compete.   Chenango seems to have some pretty good elevation which lets you hold onto your snow. 

The heat this year ia killing me, I live in PA so its even worse down here.   Its bad when u need AC up at the cabin, at home I think my ac unit finally got a break for the first time since mid July today. 

NathanS

Thanks Jason. Our property is at 1850ft. Pretty high for the east coast.

And thanks again don. I am building a better house because of all the great input I am getting.

On wife phone so don't want to type too much. Got the north and south walls up. The triple 2x12 over 9 foot header was a doozy. We used 2x4s screwed in and hanging out the wall with a 2x12 screwed on about 6 feet out from the wall as a counter balance. Only way wife and I could lift it without buying a wall jack or something. Went up just fine with the counterbalance.

Here's what it looked like after raising the wall.






Want to make a joke about the ultra safe egress window that a toddler could easily fall out of. But seriously. Lots of dumb codes, this might be the dumbest yet. Rough sills 20 inches off the subfloor. If Jabba is a guest during a fire were in luck.







Don_P

You're quite welcome, and thanks. I was on a car forum looking for advice the other day and one mechanic's signature line said "believe it or not I'm trying to help you", had to chuckle.

Remember if you put in a guard on a window it should be easy to clear from the outside coming in and from the inside coming out. Our guys can clear but it isn't always them first. We used to talk about the intent more than the letter, but we used to build for a different crowd.

The low header?

NathanS

Stairwell window. Landing is a little under 5 ft below. Code said at least 36''. Wanted to be able to see that window while sitting downstairs.

Also wanted to ask specifically for blocking for sheathing edges could I use 2x4? Thinking about thermal bridging

Don_P

I use 2x4's flatways against the sheathing. The 2x dimension makes for easier nailing through the studs or toenailing from block to stud. Functionally a 1x would do the job if you can figure out how to hold it in place while getting the nails from sheathing into the blocking. I usually put 3 nails per bay from each sheet edge into the block, 6 nails in each bay total, center then halfway each side of center.

A friend (who co'ed a 2 year major remodel today woohoo) and I were talking about that this past week. We were both working on old 2x4 frames doing blocking for sheathing then blocking for interior wainscoting. I ended up with one wall in a bedroom that only has 1/2" of insulation space between blocks  :P. The sprayfoamers will never get that filled and it isn't good to begin with. I'll catch those with can foam before they come in but I'll have a strip of about R5 on that wall. When I started I could see through that wall in places though so it is an improvement over what was there.


NathanS

Glad I asked about the blocking because it's going to make it go a lot faster.


Decided to jump straight to the roof while the weather is good. Had some help getting the joists into place, then the wife and I set the ridge board and put up a few rafters today.

I was going to do a 9 12 but man as soon as I saw how high I was going to have raise the ridge I chickened out. We are doing a 7 12.. and no small part is because the bottom of the ridge is about 4' 10" above the attic joists. I built a shed last fall with a 9 12 and I couldn't walk on it because it was so steep. Will always have a harness on, but I am thinking I'll actually be able to stand on a 7 12. We'll find out over the next few weeks.

At the lower height raising the ridge was a breeze. We slid one end into a saddle, raised the other end into an 'open saddle' and then screwed on a piece to lock the ridge in place.







About 2 weeks ago we saw a monarch cocoon on our downstairs ceiling. This weekend we saw it before it flew away. Really awesome. Not sure I'd say we have a lot of monarchs, but we see at least one every day. I think prior to having this land I hadn't seen one in years.







When I was a kid all I saw were monarchs. Not too many anymore. We'll wait till they're gone before we bush hog the fields.

Don_P

My wife's comment was "whoa that's not a milkweed, who says they're picky  :D"
I consider an 8/12 about the max to walk on, but if you get going you sure aren't going to stop on it. The conditions of the moment determine traction, yesterday or an hour ago doesn't matter. I've stuck to a 10/12 just fine and slid down it minutes later after 3 drops hit it. I was drifting on wet galvy tin on a 3/12 porch this morning. By 9 it was a sidewalk and by 2 it just didn't matter, I was a crispy critter and came down to work on other stuff. It's looking good. Be safe out there.

NathanS

Starting to think about the mudroom roof. Before doing this roof I am probably going to use it as a platform to get sheathing up to the gable roof, so it's still a ways off.

The mudroom will get a shed roof that butts up to the second floor wall. This would require a ledger board that supports half of the roof load, unless I'm mistaken. The tripled LVL was sized to take half the load of the shed roof, so we should be good there.

What is the best way to attach the ledger to the studs? Or is there an even more direct way of adding studs into the current stud bays to directly bear down onto the LVL? That seems better than relying on lag bolts, but I haven't found a whole lot of information on this. Any recommended reading?

ChugiakTinkerer

Your inspector might treat that like an exterior deck attached to the wall, which as I understand things have recently been subject to a lot more stringent requirements for attaching to the wall.  The 2015 IRC has exterior decks in Section R507, although it assumes the deck is at floor level and you are attaching the ledger to a rim joist.  I think I would go with Ledgerloks or similar over lag screws, at least two per stud.  Multiply the shear capacity of each screw by the number of screws and it should exceed the design load for the ledger.

Did you take into account the lateral load the shed roof will be putting on that wall?  You might want to throw some sister studs in there to stiffen the wall.  Would also give you some additional anchor points for the ledger board.
My cabin build thread: Alaskan remote 16x28 1.5 story

Don_P

Sorry to be slow, I was working on restocking a cane mill, with a 6' black snake up in the rafters watching us work half the night  :D

It isn't defined in the code that I know of but we usually ledgerlock a ledger over the sheathing into the studs or blocking in the wall. If the loads are looking worse I'll skip the ledger, punch through the sheathing alongside the studs and nail the rafters to the studs then fit cripple studs under the rafter down to the plate. I guess my breakline is up to about an 8' span I'll ledger, if it's longer I'll find a stronger way to support it... that is armchair engineering, give 'em time I'm sure it'll get a paragraph one day. Think about sliding snow impacts from above. I don't really see that much lateral, the main loads are vertical the way I'm seeing it. Do run ledgerlocks high and low no closer than 2" to an edge. If the ledger connections are high only it can split the ledger and drop the assembly. When you punch through the wall, air sealing can be an issue if it is a vented assembly, be neat and caulk the penetrations.

NathanS

Thanks both of you.

Don I grew up in Maryland right by the Appalachian trail.. I don't miss the black snakes. They are aggressive compared to the milk snakes and garter snakes we have on our property. Your signature should have a tip jar or something, the information you provide is invaluable.

The span is going to be 7' 6.5". I think I was on the right track with cripple studs basically creating a deep beam. If I go that route caulking the exterior rafter penetration and then spray foaming from the interior would make me feel pretty good.

Both attics will be ventilated.. leaning toward gable vents with a continuous soffit vent to create positive pressure which is what Joe Lstiburek says is best.


Completely separate topic - I used regular nails to attach the PT sill to the studs and didn't know until just now that the new chemicals they use may corrode the nails over time. Looks like I need to toenail the right nails in place all the way around the first floor.


Don_P

Bummer, yes, easy enough to renail now. That probably isn't an issue since the plates are dry service and current ACQ isn't the same as the first generation stuff which was eating metal like crazy. Still easy enough to be safe.

I keep the door open in the shop in summer and the bat population was exploding in there, so much for wishing for a control... or, be careful what you wish for  ::). There are quite a few in the sawshed, we kind of have an agreement worked out. I like them there as mousers but they can't be startling me while I'm sawing.

Tip jar is cool, send it to John  ;)

NathanS

Worked hard this week. Just about time to run the ladder framing out for the overhang. Went with Don's recommendation of going in 32" for the cantilever. Those rafters will be doubled once I through nail the ladders into place.

In the center third of the house one rafter is 24" OC (still well well well within snow load w/ 2x10 #1 SYP) so that we have some wiggle room running the stove pipe straight up from our wood cookstove.

I did a lot of this work alone, but my wife was just a huge help over the long weekend. Only reason those rake walls are done because I could call measurements down while I sat on my butt and nailed.

"Working Alone" is a great book, I used his method to easily set rafters into place alone. They were not light, many of them well soaked after sitting out for the last month+. It was pretty hands free once in place. Sometimes you gotta walk the joists, lift the rafter, and beat on the block to get things as close as possible. After moving thousands of pounds of lumber, I'm pretty sure there's no such thing as 'just right', but I got everything pretty dang close.

Rake walls are 2x4 @ 16" OC. A few reasons, one I could put a an extra ceiling joist right on the top plate and then screw down some temporary OSB as a work surface, two it is easier to wrestle 2x4s straight and a lot easier to lift into place, and three we had extra 16 footers.

Oh and I left 24" in the center for the gable vents because I'm not sure what we're putting there yet. Didn't want to have to tear anything out if we end up with something wide.























Don_P

While you were up there calling down measurements, we call that "grab a perch and holler". It can be used as a directive, as in "I'll cut you climb", or as an insult if someone is being lazy "well just grab a perch and holler"  :D

NathanS

A lot of the overhangs are framed out, but was ripping some wood today and my circular saw died. I have those M18 corldess Milwaukee tools, they are China junk. My cordless angle grinder also died after probably 30min - 1 hour of use.

I need to buy a new circular saw, I would take any first world country, but it seems like everything is made from slave labor now. Wish I had time to find an old USA saw that was just used by a homeowner.

ChugiakTinkerer

Probably plenty of old cordless tools that qualify and you could find with a little patience and perseverance.  The big question is what condition would the batteries be in?  Old NiCad batteries can have an amazing life span if treated well.  Could an old Makita or Dewalt be retro-fitted with modern battery packs?  Rhetorical question, I guess.  I don't have the answer.
My cabin build thread: Alaskan remote 16x28 1.5 story