trusses vs stick frame

[ninedriver]

I'm in the planning stages for a 30' x 40' shop. The 30' dimension will be the front where the roof peak/face side will be. I'm looking at a 12/12 pitch to match my house but may go down to a 10/12 to keep it from being "too" tall. Anyway, I've done a lot of viewing of others garages/shops and it seems most everyone are using trusses. Is this because they're easier? Or, is a 30' span too far to bridge with stick framing? My house, which has a few 12/12 peaks, are all stick framed which allows me to make "bonus" rooms and walk in storage in the up stairs/attic. So, thoughts?

 

[Lkdelta]

In-laws have trusses, it was really fast to set them up and get them sheathed over..."about half a day" to go from "just the top of the walls with no roof"...... to laying shingles....

But now, trying to jam outdoor chairs, tables up there is a bit of a pain

I have stick frame and very easy to create storage for the seasonal stuff

Both Places are only 24' X 24' though

 

[chickenhauler]

For 30', you'll need a pretty heavy ridge beam to get a clear span. Not that it can't be done, but it'll be cheaper to get trusses.

 

[viper86]

Roof trusses will easily span 30', but if you stick frame, you would (technically) need a ridge member spanning 40' that would support half the roof load. I say technically because if you look at many old garages, the ridge beam is nothing much more than a piece of 2x for the rafters to frame into. There are generally collar ties to keep the walls from spreading apart, though. If the ridge beam is properly sized, the collar ties aren't needed, and the ridge won't sag. Quite helpful if you're looking for lots of headroom.

For as steep of a pitch as you're wanting, you can probably get trusses designed to have an open area for you to create usable space in, depending on how wide you want the space to be. If you stick frame and want the usable space above, you'd either need floor trusses to clear span the 30' (which may be rather deep), or split that 30' into two spans with a beam line supported by one or more posts.

The nice part about trusses is that while your footings are being poured and walls are being built, the trusses are being manufactured. The trusses take little time to erect as compared to stick framing, so there's a time value to them.

 

[Jeff Ivers]

To span 30 feet with a 12/12 pitch, you would have to have 22 foot long lumber for each side of the roof (minimum, assuming no overhang). It would have to be dimensioned to handle the snow load in your area. This assumes no interior partitions that can be load bearing. Can you buy 22 foot lumber in your area? That is the main reason people use engineered trusses.

 

[PassnThru]

FWIW - when I had my garage built I was planning for wider than 24' until they told me that they would have to go with trusses over 24'. I didn't want trusses because I wanted the whole attic for storage so I went with 24'. Not saying it can't be done, but the more I have learned since then the more I understand the reasons. Of course, this was clear span. If you are willing to put some posts in it and maybe bring the pitch down then it should be doable. Like someone said, think about the rafter length and if they will even be available.

 

[bczygan]

Trusses simplify and speed up construction and save money. They do the engineering which can save money because they know how to use just the right materials to accomplish the job. This is especially true for typical span and load conditions. They also provide engineers seals where needed which saves money and headaches.
Now, if I were building a small shed (As I have done 7 times on my lot) I would probably use joists and rafters and overbuild it.
I like your idea of going 12/12 for roof pitch. I like nothing less.
As far as making that space in the trusses usable, get the truss company to design the truss system to take advantage of it with storage trusses designed for whatever loads and uses you want. They can basically do anything.
The idea is to define the spaces you need and want, and then get structure that will create those spaces for the least amount of dollars. Sometimes this will mean clear span trusses and sometimes this will mean other methods including steel or engineered materials. Figure out what you want to do with the spaces below and above the ceiling line and the structure will flow from that.

 

[ninedriver]

Thanks for all the speedy replies! A few things I neglected to mention, I absolutely want to avoid any posts within the structure. Also, I'm thinking of finishing off the area above to a 'Mother-in-law' type living space. That being said, it'll need to support living space weight (furniture, etc) and I was thinking about four to six foot knee walls to maximize the space as well.
I'm in North Mississippi so snow load isn't much of a factor. However, as Jeff mentioned, not sure of the availability of 22' plus long lumber...
bczy, excellent points as well, thanks.
Would anyone happen to know if trusses can span 30' and still support livable space above? I'm just trying to maximize my shop space (no posts, just open space), and maximize living space above (use shorter knee walls to increase livable width). Yes, I want my cake and eat it too

 

[ishiboo]

Thanks for all the speedy replies! A few things I neglected to mention, I absolutely want to avoid any posts within the structure. Also, I'm thinking of finishing off the area above to a 'Mother-in-law' type living space. That being said, it'll need to support living space weight (furniture, etc) and I was thinking about four to six foot knee walls to maximize the space as well.
I'm in North Mississippi so snow load isn't much of a factor. However, as Jeff mentioned, not sure of the availability of 22' plus long lumber...
bczy, excellent points as well, thanks.
Would anyone happen to know if trusses can span 30' and still support livable space above? I'm just trying to maximize my shop space (no posts, just open space), and maximize living space above (use shorter knee walls to increase livable width). Yes, I want my cake and eat it too

Sure, trusses will span that no problem. Definitely the way to go unless you do 2 full floors. The liveable space in a 30' storage/attic truss will be very small... probably only about 10-12' wide at best. You cannot stick frame an unsupported 30', your only option are trusses, having a VERY large center beam ($$$$$), or using engineered joists. A 14" TGI may span that, otherwise an open web truss will.

 

[mmhouse]

I'd suggest you go to a local truss manufacturer or pro-lumberyard that designs and manufactures trusses. Take them a sketch of what you are trying to accomplish and let them do a quick design/estimate for you. It's all done with computer CAD programs and is relatively quick and easy. Not only will it give you a good idea of cost but they can also give you ideas/options on how to accomplish your goals.

 

[mrobins297aaa]

here's a truss framed 2nd floor, this is not mine its just something I collected off the internet when I was decideing how to build my barn.

they look like real expensive trusses

 

[josall]

This might help for example on a 10/12 pitch with a 30' span with an attic truss you can get a 14' wide room with a 7'8" ceilinng.

http://www.askthebuilder.com/B203_Attic_Trusses_Room_Size.shtml

go to the bottom of page..

 

[ninedriver]

Once again, thanks to everyone for the replies! This is exactly the info I was looking for. I'm thinking the quick design/estimate from a manufacturer will be my next step, now that I know it's possible... And josall, thanks for the link, that gives me a nice idea of space.

 

[mmhouse]

Let us know what you end up doing.

 

[Stuart in MN]

The liveable space in a 30' storage/attic truss will be very small... probably only about 10-12' wide at best.

No necessarily - my garage is 24 feet wide, with a 10/12 pitch roof and attic trusses. The floor is 12 feet wide up there, with 4 foot knee walls.

 

[Falcon67]

I'm going stick on 24' because that is about as wide as you can go before jumping to a truss. Truss at 24' is about 3 times the cost of sticks. After that - have to figure it up. Can still be cheaper than a truss if you don't need a clear floor. House next door has a 28' wide living room ceiling with no trusses. Well, one sorta built-in-place "bridge truss" looking thing. Neat trick.

 

[mmhouse]

I'm in North Mississippi so snow load isn't much of a factor. However, as Jeff mentioned, not sure of the availability of 22' plus long lumber...

22', 24' and even longer lumber is available it just costs more and may take awhile to get.

 

[Spire]

I was quoted $8500 for 50' trusses, 24" on center for a 50x50 garage, 5/12 pitch in Alaska. This just for reference of course.

The same dimensions with attic trusses almost doubled the cost to ~$15,000

For some great information on Truss construction, possibilities, technical info etc, check out http://www.aktruss.com/images/AET_portfoliio.pdf

 

[dchandler60]

I am having 30' span trusses (2x8 lumber) delivered Thursday for my build (30x32) here in East Texas, They are 10/12 pitch with 14' wide 8' ceiling room, 2800.00 tax & delivery included. Allied Truss in Jacksonville,Tx . This just seemed like the way to go without having a center beam & center pole support. I priced all methods and liked this option the best.

 

[Steves32]

22', 24' and even longer lumber is available it just costs more and may take awhile to get.

I didn't want trusses.


These 2x12's on 16" centers are 28 ft & were good in stock at lumber yard.

 

[JMURiz]

I'd go with attic trusses. The added cost is worth it with the extra space, especially with a 12:12 pitch. I went with stick-built rafters on mine...but that's because it was only a 22' span with a cathedral ceiling. If I had a flat interior roof I'd do trusses in a heartbeat.

 

[38Chevy454]

I think the attic trusses are the best option for you. Gives pretty good size storage room above, open span on first floor without need for support posts, and you have a nice flat ceiling to work with on the first floor. Will you put a pull down stairs or how do you plan to get up to the storage area?

 

[Rosco]

Mine is 26' wide and I stick built it using 2 gluelam beams across the 26' span and 2X12 floor joist on 16" centers for the bonus room. Knee wall is 4' from edge and it is a 11/12 pitch. Built dormers into the plan, so the gluelam beams are sitting underneath the dormer walls. What also added strength was 3/4 inch T&G over the entire floor prior to raising rafters.

The upstairs is now sheetrocked and am in the process of mudding/taping. I also have a 1/2 bath under the stairs. Do yourself a favor and plumb it for a bathroom even if you dont plan on using it right away. Only cost me $200 for all of the rough-in plumbing for the upstairs and downstairs bathrooms.

Also used a third gluelam for the header over the garage door and man door. Header gluelam runs the entire width also.

 

[boiler7904]

30' span with a 12/12 pitch isn't a problem for trusses but they would end up being a piggyback design where you have the main truss that forms the open room with a flat top and then a second smaller truss sits on top of that.

The biggest problem I see with trusses for this build is that the OP wants an in-law suite on the second floor which I assume means a full bath and a kitchentte. Drain pipes have the potential to be a big problem - truss manufacturers generally won't let you drill any holes in the members of their trusses.

You will have to use engineered wood joists to span 30' unless there is a beam and at least 1 (probably 2) columns running the center of the building.

As others have said dimensional lumber in 22'+ lengths is available from professional lumberyards that supply to homebuilders - maybe in stock.

 

[camarotoolman]

I used 2x12"x 20' on my house, 12/12 pitch. Its 26' wide. So 30' would be 24' 26' long rafters. 2x12 ridge board. On 2' centers. You are going to be about 30' high, hope you don't mine working up high. you might have a hard time getting carpenters that will help. etc. I have 12" of insulation, which is good. Ceiling is 9' upstairs with 4' walls. Is it necessary to be 30', go long longer no wider.

 

[ninedriver]

Thanks again for the replies and suggestions.
As boiler mentioned, I'm going to try to use the upstairs space for a small visitor room space / mancave. So I am leaning towards a small bathroom / dinette with a small living space (futon or foldout couch) Kind of like a high rent efficiency appt you'd find in NY. I'm thinking roughly 35 x 14 ish after subtracting the stairs and you end up with just under 500 sq'. Still larger than most campers As far as stairs, I'd like a man door at the rear left corner, along the 40' side, and the stairs along the back wall(30')side. That way I could wall off the stairwell in the lower shop, add another man door there for privacy, and utilize the space beneath the stairs for a lower bath/wet room....
Some people mentioned I-joists? I've seen these on some home construction. Will these span 30' without support columns? Still thinking...
Also, after seeing some other threads, I'm thinking about a dormer along the left side of the roof as it would face my back yard and allow for some more room upstairs. Can dormers be done with trusses?
Man, it seems like I've been planning this in my head forever and for every solution I come up with a dozen problems(new ideas)...
Thanks again!

 

[kb2tha]

FWIW - A ridge board serves NO structural purpose. It is used only to aid in placement of roof rafters and to help maintain spacing. Not to say that one should go without one, because it only makes good sense to use one.

If you could manage to properly place the rafters without a ridge board, the rafters would rest tight against each other at the peak. You will need collar ties for sure.

As has been said already, go to a truss manufacturer with your plans and they will work up a drawing and a quote in probably less than one hour.
Ken

 

[Rosco]

Dormers can be done with trusses. This is an awesome garage build thread.

http://www.garagejournal.com/forum/showthread.php?t=22058

 

[bradweingartner]

Some places, including where I live, Stamped Trusses are practically the only allowable way to build. They claim it's due to snow-load requirements, but probably has more to do with local truss manufacturers having 'ins' with the code officials...

Either way, know your local building requirements first and foremost.

 

[worn shoes]

I went with trusses because for me it made the most sense. I wanted an open floor plan and the cost seemed reasonable too. They span 40' x 37' and look like a work of art.

 

[KnurledNut]

Check your state building codes first.

BCI-Joists will handle the span. 16" tall joist with 2x4 chord placed on 16" centers is good for 30' 4" (40 psf live load).

22" 2x4 floor trusses on 16s are good for 31'5"

Attic (room) trusses can be configured several ways. A suggestion would be girder attic trusses with jack trusses and intermediate joists. Of course this would require an experienced framer to install.

Consult an engineer.

 

[hockey88fan]

Been thinking about a second or attic trusses, having a tough time deciding between the two. I found these trusses which creates a much bigger room than a standard attic truss, I'm looking to span 28' with them.

http://bradleybuildings.com/cambridgemax.htm

 

[John in OH]

I toyed with this same question briefly when I was planning my new shop. I wanted storage space above the shop and the truss design was obviously the route that would best meet my needs.

My span is 34' with a 7/12 pitch. The resulting room created within the truss structure is 12' wide, with 8' from floor to bottom of collar ties and 5-1/2' knee walls. The bottom chords are 2x8 and the bottom chord live load is 40 psf. Floor is 3/4" T&G plywood.

Purchase cost per truss = $130 each. All trusses were delivered on one truck and installed in less than one day.

View attachment 127614 View attachment 127615 View attachment 127616

The truss route is far and away the most economical way to go if you want simple meat and potatoes construction. But if you want a real custom design, then stick-built may better meet your needs.

One word of caution if you are planning to put living space above your garage ... in my area (SE Virginia) there are strict building code requirements regarding safe access to the second floor living space. Example: You must be able to access (more importantly exit during a fire) the second floor space without passing through the lower garage space ... this essentially means the access to the second floor must be completely isolated from the garage space. Make sure you review this subject with your local building department.

 

[John in OH]

Sorry .... not sure how I screwed up the photos that should have been in the previous post, but here they are again.

 

[darkk]

I have a 2 story 30x30 garage with open span on the first and second floor. 13' ceilings on the first and the second floor has 7 1/2 ' side walls and an 11' vaulted ceiling height using trusses 24" OC. the roof pitch is 7/12 outside and 3/12 inside.

 

[Kevin54]

I didn't want trusses.


These 2x12's on 16" centers are 28 ft & were good in stock at lumber yard.

I'm interested in seeing more of this. Are you going to cut your original roof out or leave it as is? Any build threads on this?

 

[Bill Crowell]

A note on 22-foot lumber in California: I'm using 22-foot 2 X 12s for roof joists. My garage is only 21 feet wide, and the roof pitch is only 5 in 12 (plenty adequate for California), so my rafters are 14 feet long. Even so, they were a real pain for one man to lift into position.

I bought my 22-foot lumber from Home Depot, which in turn bought them from Diamond Pacific. I could get them cheaper through Home Depot than by buying them directly from Diamond Pacific.

When I first got them home, I discovered that the boards were actually 24 feet long, but they only charged me for 22 foot long lumber.

There is a lot of personal satisfaction in framing up your own roof rather than using manufactured trusses.

 

[mmhouse]

Some places, including where I live, Stamped Trusses are practically the only allowable way to build. They claim it's due to snow-load requirements, but probably has more to do with local truss manufacturers having 'ins' with the code officials...

Either way, know your local building requirements first and foremost.

I can understand you thinking this but it's really not the case.

The reason that building officials like trusses is that they are engineered so the inspector has engineer stamped drawings to rely upon - in other words they are assured that the structure meets code. This can be done with other types of construction but it often takes more effort or requires a separate expense whereas stamped drawings are typically included with every order of trusses you purchase.