Long attic trusses vs a second floor..

[rerod]

I assumed 40' raised heel attic trusses every 16" would be more cost effective than adding a second 8' level with regular 4/12 trusses. I also planned on 8/12 scissor trusses in the car lift area..

But is this the case, also considering the crane and crew needed?

For someone who knows truss prices, does upgrading from regular 4/12 40' trusses to > 8/12 attic or scissor trusses raise the price dramatically? Would it be less expensive to add another 8' level and use the cheap 4/12 trusses?
Honestly, I could DIY 14' wide spaces separated with posts, and just use 2x10's for floors and roof..

Thanks

 

[TurnipTruck]

In 2018, my 40’ attic trusses were exactly twice the weight and twice the price of the common trusses.

 

[billconner]

I think you'll find 1 floor and attic trusses is more economical than a second floor and simple trusses. Of course, less full height space with attic trusses.

Personally, if diy, I'd do the stick framing and rafters. Definitely lower materials cost. I don't mind the posts but some do. I have one in a 28 x 32. Not sure 2x10s will span 20' as rafters in Iowa, but maybe. They only were good for 14' here - 60 psf snow load though.

In place of scissor trusses, youight look at raised tie trusses. I would think the ceiling and insulation would be easier and better. Just a thought.

 

[rerod]

In 2018, my 40’ attic trusses were exactly twice the weight and twice the price of the common trusses.

Thanks..

Menards says common 4/12 40' trusses are $220 each, but couldn't get me a price on one attic truss. But if I double the price for a attic truss, seems like $220 would buy the two 8' wall studs, one sheet of plywood etc, or in other words, the extra material for a second floor.. Still guessing though.

 

[larry4406]

Attic truss has a chance to clear span 40’.

An extra floor system won’t span 40’ without serious $$$ so now you are adding a beam with posts in your way.

 

[billconner]

I look at Turnip's trusses, and it looks like you get a room 12 to 14' wide, where as a second floor is 40' - triple the floor space.

Just hard to compare without at least sketches to scale.

Balloon frame the walls so they're 4 or 5' above second floor, and use raised tie rafters so you get enough height. Could be same truss end to end for lift space. I have to think the raised tie trusses are very little more than a common 4/12 truss.

 

[nmk_61802]

Also, costs aside, keep in mind most places will have a limit on accessory building height. Either total, or compared to main structure. My county doesn't have a lot of rules, but that is one of them.

 

[finn]

I put in attic trusses on my 32x54. Don’t recall the increased cost, but it was fairly steep, and a total waste of money. If I was to do it again I would use that money to slightly increase the footprint of the building.

I never go up the pull down stairs anymore, so the attic becomes dead storage for junk that should have been thrown out. Adding conventional stairs is impractical because of the floor space wasted, even with a compact stair layout.

The only reason to go up instead of increasing the footprint, in my eyes, is if you have zoning or covenant restrictions limiting building size.

 

[Beemer]

Besides the cost, I would look into the degree of deflections and vibrations that 40 foot trusses might experience assuming that the trusses support the floor space.
Would upstairs wall finishes suffer from seasonal snow loading movement? Would anything else in there?
By vibrations, I mean when someone walks would there be noticible bounce? Human comfort level is a consideration.

In my experience wood trusses are generally designed to code minimums unless the designer or owner requires otherwise so a bit of interaction might be to advantage.

 

[rburke65]

I did the attic truss..8/12 ..32’x56’ …love the added storage area

 

[tarmy]

Mine is 32’x56’ with the “game room“ above…

 

[thammel]

Attic trusses in my 28x 32 with permanent stairs up to the attic. Attic is about 32 x 12. A great mancave and storage area.

 

[rburke65]

Mine is 32’x56’ with the “game room“ above…

I always have liked the looks of your build. Very nice

 

[tarmy]

I always have liked the looks of your build. Very nice

Thank you. That is a dream build for me and I appreciate your kind words.

 

[billconner]

Thank you. That is a dream build for me and I appreciate your kind words.

Definitely at or very near the top for aesthetics. Congrats!