Truss/joist spans

[Kach]

I'm looking into modifying the 2 story universal cottage into a 24' wide plan to better suit our needs.  I would like to keep the possibility of moving walls wherever in the future for re-configurations (we're building this for our current family of 5, but also to be a someday "empty nester" for the wife and I). 

It looks like you could use TJI's to span this distance without additional support, but I've heard you might end up with some "springiness" at this length and this would be using very wide joists.  Could you improve this somewhat by going with 12" joist spacing?  What size TJI's would I be using?

[MountainDon]

Closer spacing will reduce the depth of the engineered joist. What size would be needed can be found at any joist joist sales office / lumber yard / etc. They just need to know the span and the live load.

[Kach]

When we order universal cottage plans, what is entailed in getting them re-drawn to 24x40 and having our floorplan customized (have this designed already)?  Would this need engineering?

What should I expect to pay and does anyone know of who does this in the Puget Sound area?

[UK4X4]

Floor joist wise- you can get TJI's for your width of house,

google this see page 4

TJI® Joist Specifier's Guide - Weyerhaeuser

16" or 14" will do what you want, stiffer the better gets you a more stable floor.

Even your local lumber yard will spec a tji for you

Floor plan wise is you have full span joists, walls can be put anywhere, no engineering required

Roof wise I'm not sure whats in the plans, but if you went with trusses, they come engineered for you.

again full span trusses means you can add walls anywhere you want.

Your local building permit office will advise on wether they want engineered plans- roof or foundation.

Choose your engineer carefully......they like to charge for everything !....I had one that charged me full design cost for copying and pasting my own autocad files I'd sent him ! all he'd done was add his business header to the bottom.

[rick91351]

When we order universal cottage plans, what is entailed in getting them re-drawn to 24x40 and having our floorplan customized (have this designed already)?  Would this need engineering?

What should I expect to pay and does anyone know of who does this in the Puget Sound area?

I would imagine in the Puget Sound area seismic and soil would be required.  But like UK says call the building department of that country. 

We have had a couple engineered for snow and wind shear when our county got off in a weird tangent.  Same engineer did them both.  He was real economical.  He's office is even down an alley between a couple other business - in the old section of town.  Just a one man office.  He suggested we use a friend of his do to the drawings. 

What I am saying is shop around a little.  Last one we had done we used an architect with a flat rate - who used the same engineer.  I had most of the drawing already done myself he did the take offs and and tried to change stuff.  We had to put our foot down and tell him no just the way it is drawn - unless you see something bad designed.  He kept wanting to do a second story out of it for on down the road.  Just did not happen--- Not at all.               


     

[John Raabe]

You have some good suggestions for customizing the plan. The Universal also has a option for an internal beam and post layout that would allow standard joists or smaller I-joists. You can span the full 24' width but have the supplier size that and ask for "enhanced performance" which will give you a lower deflection.