Framing and Truss Question

[Michael Jones]

I'm working on a detailed framing and foundation plans for my proposed studio.
The nominal dimensions are 30'x40'x12'h.

I plan on having the foundation contractor set a "brick ledge" for the exterior. In normal construction techniques, this is done by nailing a 2x4 to the top of the inside foundation forms. The concrete is then poured, and after curing, the forms removed, and VIOLA! you have a concrete ledge set for the first course of bricks. (attached is a detail )

What this does though, is change the nominal dimension for the framing. Instead of 30' it is now 29'-5".

When ordering Trusses, they can be made to any dimension of course, but I'm wondering if it would be wiser to increase the foundation dimension so that the trusses can be 30' even.

Or does it even matter either way?
Anyone with framing/construction experience?

 

[Michael Jones]

Just thought I'd post this for fun.

The detailed framing plan I'm doing is 3 dimensional. (Allows me to check interferences) Here's a pic of where I'm at on it now. (Still working on it.)

 

[TexRoadkill]

I guess if you want to worry about a few inches I would be checking to make sure the inside dimensions will accomodate 4x8 sheets perfectly. Of course this all depends on the tolerance of the construction and I haven't done house framing in a long time but it seems like no matter how close you get your details there will always be something that throws it off during fab and erection just enough to make the perfect size not perfect anymore.

Another general guideline is to base the dimensions on the most expensive fabbed part so you can keep it's cost down. If the truss is the most expensive and they give you a better price at a certain length then go with that size.

 

[Michael Jones]

I think you worry about dimensions where they're critical.
Where this dimension becomes critical is at the truss.
If the trusses are pre-fabbed at 30' then each wall would be out of plumb by 3-1/2". Or you'd have to make some "pain in the ass field fit" to the truss. If the trusses can be pre-fabbed at 29'-5" then all is well. OR, I could expand the foundation by 7" and have the trusses made at 30'. That means I have to rely on the foundation contractor to accurately set his forms.

Who is more likely to work within the critical dimension?
The truss builder,
or the foundation contractor.

My guess would be the truss builder, but I wanted some other thoughts.

The foundation is the most expensive part of the 2.

 

[kristian]

Where in austin do you live? Do you need work help? i wont charge that much.

Kidding, but what area do you live in? I'm near campus since im a student. I know a really good local band you should go see, they are really good.

thats one of their songs i recorded. they insist on 96kbps mp3s for size, i think it sounds ok, but 128 would help their cause.

 

[Michael Jones]

kristian - I'm about a mile and a half west of the "y" in Oak Hill, out off of hwy 290.
I'll start the permitting process with the City of Austin as soon as I have the detailed plans finished.
I'm hoping to have construction started in feb. or march of '03. Sooner if possible.

Good job on the recording. Where they playing out at?

 

[knightfly]

Michael, the truss places I've talked to (OK, only two, and not in Texas) fab to YOUR specs. No sweat off their nose if you want 29 ft 6-3/4 inches total span - just make sure they understand WHERE you are measuring from, so both of you are on the same page. Usually what they want seems to be the exact measurement from outside of wall to outside of wall.

If you are going to want heavier than normal chords, etc, so you can use the trusses to suspend an isolated ceiling or three, and/or triple layers of sheet rock, be sure to mention that too.

Depending on your plans (didn't look, sorry) scissor type trusses could give you a vaulted ceiling - more headroom, better acoustics, just as strong... as long as that doesn't throw off the symmetry of the mix position, should be cool... Steve

 

[kristian]

They play at The Vibe on 6th street. Incidentally they are playing as I am writing this. I didn't know that, and I had a late class today. But their usual slot is Thursday or Saturday either 10-12 or 12-2.

 

[Michael Jones]

Michael, the truss places I've talked to (OK, only two, and not in Texas) fab to YOUR specs. No sweat off their nose if you want 29 ft 6-3/4 inches total span - just make sure they understand WHERE you are measuring from, so both of you are on the same page. Usually what they want seems to be the exact measurement from outside of wall to outside of wall.

If you are going to want heavier than normal chords, etc, so you can use the trusses to suspend an isolated ceiling or three, and/or triple layers of sheet rock, be sure to mention that too.

Depending on your plans (didn't look, sorry) scissor type trusses could give you a vaulted ceiling - more headroom, better acoustics, just as strong... as long as that doesn't throw off the symmetry of the mix position, should be cool... Steve

knight - thanks for the info. I talked to the truss maker yesterday. They reiterated what you said. They also seem to think it's better to keep the foundation dimensions as simple as possible, and let them fit the trusses to the final dimensions.

Originally, I had planned to use a scissor type truss, but after talking with sjoko, he recommended something that WAS NOT symetrical. So I decided to use what's called a "cathedral" truss. It's not symetrical, but still has a vault for more ceiling height.

Attached is a new picture.