Garages and Carports - Building 12x14 storage shed.. framing questions

We would like to build a 12x14 storage shed. We've already poured the slab, took the forms off today. A few paw prints where our chocolate lab helped with the finishing, but over all not a bad job. Now the tough part.

Home Depot printed us a plan for a 12x14 shed, but they don't include any measurements for framing the window and door openings. I had to figure them out on my own, using the 16" centred studs and the size of the window opening as a reference.

All this got me thinking. I read that spacing the studs 16" on centre, speeds up the drywalling because the ends of the sheets finish in the centre of a stud. But what about the outside where I will be covering the walls with plywood sheathing? What is the normal way to install the outside sheathing, since the studs will not be 16" on centre from the outside corners, but 19.5, 35.5, 51.5, etc, if I calculate 3.5" for the back of the corner stud? I was thinking I could start my sheathing on the same stud where I would start a sheet of drywall. This would leave the back of the corner stud bare, but I could cover that up after with a 3.5" strip of sheathing afterwards. Is that the right way? Also is it OK to use the 1.5x3.5 "two by fours" to build a shed, or do I need to use real 2x4" kind?


Also I also don't know how big to rough in the opening for a door. I want to install two 36x79 steel doors together, so I can open both for a 6' wide doorway. My father in law says I'll need to double the studs on teh side of the door opening for the extra weight of those steel doors and really big hinges.

I was planning on doing that anyway. But anyway, how big should the hole be. I've decided not to put a mud sill on the floor, so the bottom of the door would need to be just above the concrete slab floor, then I'll put one of those plastic trims to keep the wind from blowing in under the door. All my headers will be doubled 2x8s + 1/2" plywood, since that's what I used to pour the concrete.

Hi works from home, Ok, I'm not being mean, but the list of little details is far too long to cover here. Example: You layout your studs 16" oc from the outside, with the first stud coming in being 16" from the edge to the center, then 16" oc from there on. Now you will need nailers on corners and "t" walls, that's a stud that will catch the edge of the sheetrock. Now depending upon your siding and how you plan to finish your corners, you might want to cheat the studs over a half inch or so, so the siding will overlap and form a neat corner. Then you have to locate your windows and doors and place full studs 1 1/2" to each side of the mfg recommended rough opening. That leaves room for the jack studs that will support your header. If your walls are 8' then your 2x8's will be too short, so you will need to install cripples at the 16" oc spacing. There's more, and that is just one wall. A carpenter who does this all the time would layout a triple layer of 2x4's to mark all at once. Two would form the top plates and one for the bottom.

Now, you can do this, but you will need some on-site help or a very good book. If someone can do the layout for you, with a step by step, it is a lot of fun. But dealing with nothing that fits where it is supposed to, and this could be your last project :).

Let's see what some of the pro's have to offer.

Bud

"This would leave the back of the corner stud bare, but I could cover that up after with a 3.5" strip of sheathing afterwards. Is that the right way?" --- No, you want the sheathing to tie the building together, always measure from outside corner.

"Also is it OK to use the 1.5x3.5 "two by fours" " ---- Yes, this is nominal (actual) measurement. "or do I need to use real 2x4" kind?" -- never seen those except coming out of a 1900 house.

"I want to install two 36x79 steel doors together" --- Yes, double trimmers next to a king stud, each side. Frame the rough opening as per manufacturer. You know they have to close on a central astregal that is attached to one door? Miller's guide to framing & roofing - Google Books (http://books.google.com/books?id=SYPJaoUEjaUC&pg=PA202&dq=framing+a+double+door&as_brr=3#v=onepage&q=framing%20a%20double%20door&f=false)

Residential Framing: A Homebuilder's ... - Google Books (http://books.google.com/books?id=0SCGVmOUh1kC&pg=PA124&dq=framing+a+double+door&as_brr=3#v=onepage&q=framing%20a%20double%20door&f=false)
Be safe, Gary

"This would leave the back of the corner stud bare, but I could cover that up after with a 3.5" strip of sheathing afterwards. Is that the right way?" --- No, you want the sheathing to tie the building together, always measure from outside corner.

here's a picture of the plan home depot gave me for a 12x14 building. I traced it out so it's 99% scale of what they gave me.

Looking at this plan, it appears to me the studs are centred at 16" from the inside corner, for drywalling purposes. But that will make putting up the sheathing much harder.

What I had in mind was to add a stud, 96" on centre from the outside corner, so when I put up the sheathing, I'll be able to put up an entire piece and have the end finish in teh centre of a stud.

http://img11.imageshack.us/img11/6639/shedwall.jpg

Hi works, I can see how you would be confused.
The 12 ft. wall is 16"oc all the way across, first stud on the end and next stud centered on 16". 12' wall and it works out evenly.

But the 14' wall, they cheated, since they wanted to center the windows. You simply start the outside sheathing with an approximate 36" piece of sheathing to reach the center of a stud. Then you end with a similar piece and avoid any small strips of sheathing, thus tying the structure together.

Now, the exact numbers will vary slightly, as your starting place is the slab. First question is, do you want your sheathing to be flush with the slab, or the frame flush, with the sheathing overhanging by it's thickness. And is the slab square.

Measure the slab exactly in 4 places, twice in the length and twice in the length. Then measure both diagonals. What you are going to establish is the best possible "rectangle" for placement on the slab you have. I know you poured it, but measure it again. Those numbers will give you the start answer.

Now, how is the drainage around the slab? If the ground slopes off well then a single bottom plate may work. If the ground is flat and not far below the slab, then I would suggest a double bottom plate.

I'll wait for the numbers.

Bud

Hi works, I can see how you would be confused.
The 12 ft. wall is 16"oc all the way across, first stud on the end and next stud centered on 16". 12' wall and it works out evenly.

But the 14' wall, they cheated, since they wanted to center the windows. You simply start the outside sheathing with an approximate 36" piece of sheathing to reach the center of a stud. Then you end with a similar piece and avoid any small strips of sheathing, thus tying the structure together.

Now, the exact numbers will vary slightly, as your starting place is the slab. First question is, do you want your sheathing to be flush with the slab, or the frame flush, with the sheathing overhanging by it's thickness. And is the slab square.

Measure the slab exactly in 4 places, twice in the length and twice in the length. Then measure both diagonals. What you are going to establish is the best possible "rectangle" for placement on the slab you have. I know you poured it, but measure it again. Those numbers will give you the start answer.

Now, how is the drainage around the slab? If the ground slopes off well then a single bottom plate may work. If the ground is flat and not far below the slab, then I would suggest a double bottom plate.

I'll wait for the numbers.

Bud

Bud..

The slab is 12x14 and perfectly square.

I planned on having the bottom plates of the walls laying flush with the edge of the slab. Not sure how far the sheathing should overlap the concrete.

I made the slab high enough so I could overlap the siding over the concrete by a couple inches and still leave enough bare concrete to pass the string trimmer.

Today I backfilled around the slab, giving it a good slope for water to run away from the building, and I still have a good 3-4 inches all around.

What do you think of my idea, of putting in an extra stud 96" from the outside corner, so I don't have to cut the sheathing any more than necessary.

If you overlap your sheathing over the slab, you will need some metal flashing to prevent the sheathing from coming into contact with the slab. I would overlap an absolute minimum and keep all of the height above the splashing water as possible, but that is me. The extra stud isn't necessary if you follow the correct layout. Take your drawing and label every space and stud, and decide on how you are going to position the sheathing. Pay attention to what overlaps what. There is a difference between a 12' x 14' shed and a 12' 1" x 14' 1" shed, make sure you account for that. Use a pressure treated bottom plate and pressure treated around any door frames. Follow code on bolting the walls to the slab continue that metal flashing under the bottom plate. Seal the flashing to the slab and seal the bottom plate to the flashing. Still a lot of details, but not sure if I can catch them long distance. Bud Now, just as an example as to how everything has to start at the beginning, you asked Home depot to provide plans for a 12' by 14' shed, but now you want to build a 12' 1" by 14' 1" shed. The reason that shows up is the layout of the walls. Look at your drawing for the 14' wall. The top plate overhangs on each end.

Bud, I think the 14" walls are 3-1/2" short on each end, as they are measuring the top plate. Unless you mean they did not shorten the walls 1" for sheathing? This is standard with the sheathing outside of the slab and square footage measurments. (The way I was taught). Framing flush with slab.

Works, did you install a vapor barrier (plastic 6mill.) under the slab? If not, use some sill sealer under the bottom plate and/or flashing that Bud said. I would turn the second stud from each end, 90* (flat) facing the 14' walls for the three stud corners. 3-1/2" Foam Sill Seal (http://www.lowes.com/lowes/lkn?action=productDetail&productId=13280-46086-652248&lpage=none)
If this is being inspected, you need to add cripples under the window sill ends, 4 total, for wall shear flow.
Be safe, Gary

"
"I want to install two 36x79 steel doors together" --- Yes, double trimmers next to a king stud, each side. Frame the rough opening as per manufacturer. You know they have to close on a central astregal that is attached to one door?


The guy at the store showed me how to make an astragal from two strips of 1x2" pine (actually 3/4" by 1 3/4"), then nail one to the door.

If both doors are 30" across, and I need 3/4" for the astragal between them, how much do I need for the "reveal"

I want to use 1 x 5 pine boards for the door jamb, and have the hardware place cut the hinges on them to match the hinges on the doors

Move around on this site for other books on the subject: Carpentry - Google Books (http://books.google.com/books?id=YY_RyFaRjAQC&pg=PA606&dq=building+double+exterior+doors&as_brr=3#v=onepage&q=building%20double%20exterior%20doors&f=false)
Be safe, Gary

To frame a rough opening for two 34" doors, I'm going to use a 2x8 built up header.

Should I double up the trimmers for an opening this wide? The door will be in the front of the shed. The roof joists will be on the side wall, so I don't expect there will be tremendous load placed on the header.

Double gives the exterior trim something to nail into.
Be safe, Gary