Hello,
Just wanted to run a couple questions by you guys since I’m going to be building my (first) shed – what can I say, I was inspired by the recent FHB issue.
I have a 12 x 12 concrete slab already poured and ready to go. I was going to implement many of the techniques in the article, however I have a couple questions.
I wanted to make the shed exactly the same size as the shed pad to avoid any water potentially making it’s way to the bottom plate of the wall framing. That being said, what is the best thing to use to attached the framed wall (2 x 4) to the concrete pad? I was going to use tapcons, however I wanted to use PT lumber for the bottom plates only just in case it does see some moisture. I was thinking about stainless steel, but I hate how soft it is and it usually strips like crazy trying to screw it in. Any suggestions????
Also, since the shed is going to be 12 x 12, I was thinking of a 2 x 8 rafter beam (maybe I’m not using the right term here) – the beam that supports the roof. Is that sufficient?
Lastly, it’s a long story, but I have a 9 foot wide x 16″ tall transom window that I can’t return to the window company that’s sitting in my garage. I was going to put this in the side of the shed since it’s free. Is there any additional framing considerations b/c this is such a long span being 9 feet? I was going to double up the header, but other than that I was just going to treat it like a regular window frame.
I think that should be it (at least for now), but I may need some help as I work on it.
Thanks again.
Replies
Others will be along shortly to give you better answers, but I'll just put in my 2 cents (I am no expert, but I worked as a framing carpenter for a year and a half and I have been doing remodeling with a licensed contractor for about ten years): I would use construction adhesive (comes in tubes and you use a caulk gun to put down a wiggly line) where your wall plate will go. You know to frame the wall while it is on the slab, measuring the bottom and top plates right from the slab and then standing the wall up, right? (I would even put the sheathing on while it is on the slab, but you may not need or want sheathing on a shed.)
You should really have put anchor bolts in the slab, but there are several ways you can still do things--I, personally, would put one course of concrete block on the slab perimeter and fill the cores with mortar and put the anchor bolts in the mortar every six feet, but if you are bound and determined to put the walls right on the slab, you can epoxy anchor bolts into holes drilled in the slab and drill holes in the bottom plate of your walls and put washers and nuts on the plate to anchor the walls down. I would still use construction adhesive under the wall plate, or at least use sill seal (a flexible blue plastic foam about a quarter inch thick that comes in rolls) under the plates.
Some people here say they have used Tapcons with PT and it has worked fine. I don't know. There are crooked pins that you hammer down through holes drilled in the plate and to holes drilled (using hammer drill or rotary hammer) into the slab--I don't know if these are available in stainless steel, but they are supposed to hold very well. There are also pins (nails) that are fired through the plate into the slab using a special gun and .22 blanks. Doubt that those are available in stainless steel, but many walls have been built using those to attach the bottom plates to slabs. I think between the adhesive and the weight of the walls, you are probably okay. The advantage to actual bolts is that they are thick (thicker than nails or Tapcons) and it will be a long time before they are rusted away even in PT wood.
In my opinion, you will need much more than a double top plate over a nine foot long window, unless it is going in the gable end of the shed. I would look it up (or someone here will probably be able to tell you what you need) to see what size the header should be--I'm thinking double 2x10 with half inch thick plywood or OSB between. This is if it goes into a wall where the rafters are landing (a wall bearing half of the roof load).
The ridge and the size of the rafters and so on depends on several things: do you want a structural ridge? (Such a ridge is supported very well at each gable end and holds up the roof--takes much of the weight of the roof off the side walls (where the eves are) and is probably not what you want/need in a shed.)
If you frame a regular roof, the ridge can be a single 2x8, as long as the rafters are in pairs that are nailed in on opposite sides of the ridge, exactly across from one another. (In fact, you don't even need a ridge board, but that can get complicated for someone who hasn't done this before.) I would put at least one "ceiling" joist across in the middle (horizontal member from one wall's top plate to the opposite wall's top plate) to keep the walls from spreading--not a major problem in a 12' long shed, but.... For a shed, I like a gambrel roof ("barn roof") because it has more head room at the walls. They are harder to frame though.
With a 12' x 12' shed, the rafters could probably be as small as 2x4's, but if your roof has a low slope or you get lots of snow, you should probably go with something bigger--2x6 or even 2x8. Again, there are tables that give the size for these too.
That's a start to get you thinking until others reply.
Hi Grandchat, welcome to BT.
First off, consider using Simpson Titen HD screw anchors ( http://www.simpsonanchors.com/catalog/mechanical/titen-hd/index.html) to attach the mudsill to the slab. they can be driven with an impact driver and are comparable to a traditional anchor bolt.
A 2x8 could be sufficient for the ridge beam, but you need to offer up some more infromation on how the shed will be framed. Same goes for the window header. A doubled up header will work fine, but it would be nice to know how the roof will be framed, and therefore, where the load path will be. Also, which wall the window will go in (gable wall or side wall).
Justin Fink - FHB Editorial
Well, I'm going to frame the roof exactly how it's detail in the recent FHB magazine article (the one just before the new one came out about factory applied siding finishes).
I was going to use a 2 x 8 rafter, then I was going to use 2 x 4's, 16 o.c. for the rafters. I was going to cut the bird's mouth and attach it to the top plate which I was going to make a double top plate.
As for the window, I was thinking of a side wall, but it it's better on the gable end, thne I can do that too. Really no preference, just wanted to use up something that's "free" and give it some light.
The slab is as close as I think you can get to being level, but it's not perfect. I live right by Detroit, MI and I'm pretty protected from major winds, but I do get some snow.
I was going to use a 5/12 pitch to match the pitch of my rear covered porch. Should I use 2 x 6's for the rafters instead of 2 x 4's or should I be ok?
Any other suggestions or recommendations would be greatly appreciated.
Thanks again and I'll make sure to update on the progress w/ pics hopefully.
2x6 rafters will be fine in such a small building. i do not like to cut birds mouth in 2x6, leaves very little wood left. I would run a 2x6 across with the rafter, in effect a ceiling joists. This will help keep the walls from spreading.
Window in the gable end will eliminate need for much of a header.
how would you attach the 2 x 6 ceiling joist to the top plate of the wall frame? Just toe-nail it, or use some type of Simpson hardware? Thanks.
Toenail it. I have some problems with the shed as I would have built it with 2' on center studs, plenty stong and less expensive, but.
I can do whatever if you want to you think would work best. Can I use 2 x 4, 2' O.C. and still use the 2 x 6 rafters and ceiling joists? Just want to make sure - thanks again..
Yep, make the rafters 2' on center over the studs and now you are a framer!! (stack em)
grandchat,
How you making out on the shed project?
Still haven't done the shed yet. I just got the final grade completed, installed the sprinklers and laid down seed, so I have to wait for the grass to start up so I can trample it when I build the shed. I'm just finalizing the plans now and debating on whether or not to use 24" O.C. or 16", and also I want to make sure that I can do everything involved. The only thing that makes me nervous is the soffits after I'm done, but I can worry about that later.
I'll definately keep you guys posted and hopefully some pics. This will be my first shed, so "cross your fingers"!
Thanks again.
Frammer52,
Sorry to keep bugging you on the details of this, but when you say "stack 'em", I'm assuming you are referring to stacking the top plate, right? If not, then I'm confused.
This is likely a stupid question, but in order of operations, would you attached the ceiling joists to the top plate first, then attach the rafters to the ridge beam, then to the ceiling joist?
Last question (hopefully), is 3/8 plywood ok for the roof sheathing for the shed? I would assume yes, but just wanted to make sure.
Any other tips / recommendations is greatly appreciated. Thanks again.
stacking is refering to rafters over studs, then put in ceiling joists. 3/8 is fine, I use 7/16 osb with no problem
3/8" is fine where?
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3/8 sheathing is good for a shed. Now, if you're thinking 3/8 rafters, yeah, that's not a good idea.I don't like 3/8 roof sheathing on a shed, but I put it on mine. Everything was free, and it's still standing.
It will work for what he is doing.
After seeing all your guys input, this is what I'm going to do:
- 2 x 4 framing 24" O.C.
- 2 x 6 ceiling rafters and ceiling joists (no bird's mouth)
- 3 x 8" sheathing for the ceiling
- 3 x 8" sheating for the walls
- regular steel pre-hung exterior door
- the simpson titen galvanized bolts for the bottom plate
- I'm going to "double-up" the top plate for the walls just to be safe?
If there's anything else I missed, just let me know. Thanks again for your help and patience. I'll keep you guys posted on progress.
If going to 24" OC framing I would use at least 7/16" OSB for the roof. The shingles are more likely to break down at seams with 3/8" Besides, cost is about the same.Use at least one rafter tie ( ceiling joist) to complete a triangle and you can use anything you want for that ridge beam.Definitely keep the window in the gable end, not a side wall where the rafters land.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
last question - I'm starting tomorrow.
Would you frame the 4 walls like a box, then frame the roof on top. Or, would you frame the two walls, then frame the gable end walls including the roof gable (like the recent FHB magazine article), or using full height "rake wall studs".
I'm leaning towards building the 4 walls first, then frame the roof and lift it up and attach the rafters to the top plate of the walls since I'm going to have that 9 foot wide transom window on the gable end. However, it looks like framing it like the article suggests would be easier and quicker, but I don't know if this type of framing will be an issue with a 12 x 12 shed?
Any thoughts? Thanks again.
Just like a house, waals and then the roof. Sheathe the walls before the roof as it helps add ridigity.
Good luck, tomorrow I will be online but sat no, so if you want me make it fri.
thanks again. I'll keep you posted.
Frammer52,
Well, I'm almost done the shed (I'll post pics soon). I just have to do the trim, soffits, fascia, hang the door and install that damn 9' transom. I have a couple other questions. First, for some reason I never thought of a potential issue with the transom. It's made with a 6 9/16" jamb for 2 x 6 construction since it was originally supposed to go in the house. Now I have 2 x 4 walls in my shed to install the window to. What I was thinking of doing is pushing the window out so my 5/4x6" trim will cover the window - this will not leave me a lot of wood jamb to nail to the window frame, but I don't think that will matter since most of the weight is in the glass itself and that will be directly overtop of the window frame (2 x 6" stacked together on end). This will likely leave me about 2" of wood jamb on the inside of the shed beyond the window framing. Will this be an issue besides looks? Also, the other thing I was thinking of is sticking it outside even more and build up some additioinal moulding and caulk it up pretty good to deal with any water issues. Any other thoughts?
Also, the other stupid thing I didn't think of is I ended up using 2 x 6's for the roof rafters. As I said above, I'm using 5/4x6 for all the trim and fascia. I'm using 3/8" plywood for the soffits (with some venting installed). Now when I install the 2x6 fascia and make it flush with the 3/8" plywood, I have about a 1" space due to the 2x6 roof rafter + the 3/8" plywood. I was going to rip some 1x6" stock and use some PL premium and a some finishing nails to cover up the gap. I overhung the shingles, so once they start to fold over, you won't even see this "fix". Again, I'm going to caulk the seam just to be safe. Do you see any issues with this or have any other suggestions?
Thanks again.
You need to back up and clip the bottoms of the 2x6 rafters. To get it right, measure done on the face of the rafter 5 3/4". Then cut a level line. This will make the facia fit.
Hi,
where are you? Do you have any wind conditions you have to worry about?
what kind of roof will you have? the building is square.
if you have gable ends, will the window go in a gable end?
IIRC it's the header depth that's important, not that narrow headers are good things.
since the building is 12' and the window is 9' might consider just having the header go the whole 12'.
you can put down a sill plate to attach the wall to, is your slab level?
bobl Volo, non valeo
Baloney detecter WFR
"But when you're a kibbutzer and have no responsibility to decide the facts and apply the law, you can reach any conclusion you want because it doesn't matter." SHG
You may want to ask your questions of the building inspector, since your 12x12 shed is over 100 sq ft and thus requires a permit under the international building code that has (in theory) been adopted everywhere in the US. The inspector will have to approve your plans anyway.
Laws are different everywhere.Here, 12-1/2 by 16 is fine. (200 sq ft).When I read the title, I thought this was going to be about a 2-door shed...;o)
Trying to reason with someone who just wants to argue or insult, is not a reasonable pursuit.
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With two doors he could park a roadster next to the coupe
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Check with your Planning and Zoning, or Code Enforcement types first.
In many areas, if it is 100-sqft, or less, and doesn't have electrical or plumbing; it doesn't require a building permit. Now is the time to find out, instead of after you have it completed, and they come fine you. (From, my "Lessons learned the hard way" file.) Luckily they let me take 4-ft off the 14-ft walls, to cut the 10X14 shed back to 10X10, and leave the roof covering the front like a porch.
As to your question, I second the notion of building it on a concrete masonry unit (cmu) base course with the cells filled. The cmu, comes in 4-inch heights, so you don't have to raise it much, and it would be easy to have the sheathing hang down an inch or so to cover the top of it. I would run the anchors all the way down into the slab.
The window, I would look at putting in an end wall, as it is non load bearing, and would be easier to do.
I just built a shed and I used borate treated bottom plates to avoid the problem with corrosion of the fasteners.
I live in an area where termites aren't that bad. Some places they are everywhere.