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Building a 20' x 20' wood frame garage

76K views 38 replies 15 participants last post by  bgbrown125 
#1 ·
Help Needed Please
I am putting together a materials list to build this 20' x 20' wood frame garage on my asphalt driveway. This will be the biggest building project that I've tackled! I've built a 10'x12' shed, a large multi-level deck and a few other small out buildings.
I need some help getting the materials list together, specifically the lumber needed for framing it. I am purchasing pre-built trusses (9 reg +
2 gable at 6/12 pitch with 12" overhang).
I also need a little guidance on getting started with the framing. OK, maybe a lot of guidance!
Any help that you could give me would be greatly appreciated. I'll take anything that I can get: directions, a website, etc.

Thanks in advance,
Barry in Western N.C.
 
#2 · (Edited)
Help Needed to Build a 20' x 20' Garage

Help Needed Please
I am putting together a materials list to build this 20' x 20' wood frame garage on my asphalt driveway. This will be the biggest building project that I've tackled! I've built a 10'x12' shed, a large multi-level deck and a few other small out buildings.
I need some help getting the materials list together, specifically the lumber needed for framing it. I am purchasing pre-built trusses (9 reg + 2 gable at 6/12 pitch with 12" overhang).
I also need a little guidance on getting started with the framing. OK, maybe a lot of guidance!
Any help that you could give me would be greatly appreciated. I'll take anything that I can get: directions, a website, etc.

Thanks in advance,
Barry in Western N.C.
 
#10 · (Edited)
I'm not going to do the take off for you because everyone frames differently. But I'll give you some starter tips.
Over estimate on your materials. There's gonna be a few pieces in your load that are junk. You can return what you don't use.

So here we go...........

Starting with your sill, shoes & plates.

Your perimeter = 80 lineal feet with 16' removed for your garage door. Do not deduct for the man door

PT sills
(2) 10' for the rear wall
(4) 14' for the two side walls. (the waste will be your 2' pieces for your front wall)
2x6 (or 2x4) shoes the same
(8) 12' 2x6 (or 2x4) top plate
(8) 12' 2x6 (or 2x4) double top plate
8' studs (assuming 16" o.c.) estimate 1 per foot (use this so you have enough for jacks, corners, sills bracing)
Sheet siding I assume is t-111. 12 sheets for your 3 full walls
6 sheets for your overhead door wall and gables.
Roof sheathing is the roof square footage (not the foundation footage) divided by 32
Trim is all linear measurements - repost when you get there if you need help with estimating that. I would order the trim package to be delivered separately.

But in all cases ...even trim ....buy extra....please do yourself this favor....

Good luck and we'll guide you along with any questions.
 
#12 · (Edited)
Materials list add to top:don't forget the garage hdr,nails,tyvek or house wrap,button caps or staples,1x4's for truss standing,2x4s for wall bracing and gable bracing,2x6 for fascia,and gable rakes,stainless nuts and washers for anchor bolts,and an attic access staircase.If you got nail guns start with 2 boxes of 3 1/4 let say paslode for paslode guns 2 boxes of 2 1/4,.5,000 slap tacker staples galvanized,that should also be enough for felt paper,3 small boxes of cap nails to help hold from wind the house wrap and felt paper.you can also purchase gutter apron and drip or roof edge and install right after you lay the felt.Depending on your first row you may want to use ice&water shield instead of felt paper.Then you got gun nails for roofing gun 1 box should be plenty 1five lb.box of 3 inch for cap.Always forgotten.Hdr=2x12 service dr hdr=2x6.:whistling2:after all completed use your bracing for garage door wrap/if wraping door will aluminum use on exterior and interior.Garage door hdr should be 16'10''tripple cripple with a 1x8 wraping underside should be treated.concrete opening should be16'5 1/2"/i run a cripple down to slab,in other words 2 cripples on foudation and one down to slab along with 1x8.{p.s.buy hurricane clips and hanger nails for anchoring roof trusses to wall top plates good thing to do,Optional}
 
#16 ·
Put a lot of emphasis on a foundation that is perfectly square, and with L bolts sticking up and out of the concrete .You mentioned blacktop, so this idea you may not be able to do,and thats have a inch and a half lip (step) where garage door comes down. It helps to keep the cold air out,with a good seal. Have the garge door installed when you do that work in that area.
 
#18 ·
Good thoughts Bernie
I like to see the top of the floor 3-4" above grade with an apron transition from floor height to grade.
This really helps keep water and snow out of the garage.
You can create the apron when you patch in the asphalt since you'll be digging the existing asphalt up anyway when you set the concrete forms.
 
#21 ·
3-2x12's won't even work...... 1/2 of 20' span, plus o.h. is 11' x 16' dr. x 45# per sq.ft. = 7920# (30# live load-snow + 15# dead load-drywall/insulation)

3-2x12's, fb.1600, Doug fir/Larch, #2 = carry max.4700#

You'd need a 6x12, Df/L, Dense #2 ($$$) to match the 2- 1-3/4" x 11-1/4" LVL's.that will carry 9000+#. pp.#5; http://www.parr.com/PDFs/LP LVL 1.9E.pdf
Notice: pp.#2 = 3-1/2" beam requires 3" of bearing for 7875#, you have 8k# and need a 4x4 (9200-#) under each end for 3-1/2" bearing. Be sure to show this in your plans to the City/County for the permit.

Gary
 
#22 ·
Getting very basic carpenter work here, in building one wall. Use a treated 2x4 for the bottom plate, cut so the seam, so its under a up-right 2x4, as you'll have to have a pair on edge,one green, one regular to start with, but have the regular lumber seam under another stud, or use a 20 foot 2x4 if you can get them. Hold together with c clamps (don't laugh pros) and use a small framing square, and start marking off for your layout. Put an X on both pieces on the end, ,come out 1 1/2 inches draw a line, 1 1/2 inch space, draw another line then x. Hook your tape on end pair of plates and make sure your exterior plywood breaks on a stud. Rough frame everything from same direction, on both sides of building.
 
#24 ·
Once your walls are standing, and since you have blacktop,and have several outside wood bracing to help keep it from spreading, use a come-along in the middle inside up high ,using rope,chain or whatever. You can have perfectly plumb walls, but in the process of setting trusses,jerking to get them right ,walls tend to move, just check when your done. It pays to have a string on blocks, front to back, and keep an eye on it. When you do your outside sheeting ,have a drip aluim off-set piece between the upper and lower sheets. You might even consider nailing on a sheet of that plywood for the walls while its on the ground, or if you have enough help, put it all on, including the window. 6/12 pitch roof, so nail on a 2x4 on the sheeting for a shoe stop if your using neighbors, and nail 2feet up from edge, so you have room for first course of shingles. Elvis Presley music, and cold beer afterwards is like christening a ship.
 
#25 ·
Garages are fun projects for diy'ers. However, it really helps to have at least one person on the job that is a good framing carpenter. It will eliminate a lot of mistakes and grief and the diy'ers can learn the right way at the same time and have a good time of it. I built a 24 x 36 garage for a younger cousin of mine. He had four of five of his friends show up along with himself. I did all the layout work, showed the guys how to use the nail guns and how I wanted things done. They did a good job and we got the whole thing up in one day, with the exception of shingles, siding, and overhead door. The girls had a small feast of a barbecue cooked up for us and plenty of beer at the end. And it was one of those summer days when it hit about 95 degrees and plenty of sun.
Mike Hawkins:)
 
#28 · (Edited)
Change of Plans / Garage is now a Carport - Semi-enclosed

Well, I've procrastinated as long as I can. The primary reason for procrastination is that I have some physical limitations and I do not think that I can do the woek associated with a foundation.

The 20 x 20 garage will have to be a semi-enclosed carport. As I stated, this will take place on an asphalt drive. I plan to cut openings and "plant" posts as need to support the structure.
I still plan to have the 11 trusses built 5/12, 12" overhang. What spacing should I use for the support posts?
Help with materials list and everything will be appreciated.

Am I all wet in doing this or can I make it work.
Thank you again

Barry
 
#29 ·
Everyone I know that has "settled" for a car port say the same thing: should have spent the extra for a real garage!

If you can't do the footing/concrete work, hire it out. Yeah, it adds to price (couple grand perhaps in labor), but do it once and do it right. Concrete work should always be done by experienced people because it is the foundation of any structure and you do not want it cracking, settling, etc.

Lots of people have already given you lots of advice on a garage, so take the advice and build a true garage.

Just my 2Cents.
 
#32 ·
Everyone I know that has "settled" for a car port say the same thing: should have spent the extra for a real garage!

If you can't do the footing/concrete work, hire it out. Yeah, it adds to price (couple grand perhaps in labor), but do it once and do it right. Concrete work should always be done by experienced people because it is the foundation of any structure and you do not want it cracking, settling, etc.

Lots of people have already given you lots of advice on a garage, so take the advice and build a true garage.

Just my 2Cents.

Thanks, but not an option for me
 
#30 ·
This idea may not be code approved but you could do this, since you were going to dig for post anyway. Snap chalk lines on the blacktop,make sure the x measurements (corner to corner the same) use a pick or a jack hammer and dig down at least 3 feet both corners and two holes in the middle. The idea here is to pour a concrete beam on the blacktop and in the holes all level, so you'll have a good base to work from. Just use re-bar in all the concrete. The framing lumber used here can be lumber that you'll need for the building itself. Just get some threaded rod to keep the concrete from spreading in the form work (lots of them). Bury some L bolts in the concrete to hold walls down. You must have a level base to work from or you'll fight it from the start. If you get the building out of square it'll show up in the shingles.
 
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