[Greenbuilding] Advanced Framing/OVE in Midwest?

[douglas e lamb]

2x6's @ 24"o/c is used hear in central Ohio often. Builders are cautious
when structural support is an issue. I've seen various methods of diagonal
metal strapping and plywd cornering. The only time window sag becomes an
issue is when a window is built over a basement vent (window)and not
properly linteled and if the height of the window exceeds wind loads. Then
we use steel angles or other steel shapes tied to the foundation as a means
of shoring up the jacks. There are other considerations using 2x6's such as
species and grade of lumber to be considered also.   

-----Original Message-----
From: greenbuilding-bounces at listserv.repp.org
[mailto:greenbuilding-bounces at listserv.repp.org] On Behalf Of Chris Green
Sent: Sunday, March 04, 2007 4:28 PM
To: Greenbuilding at listserv.repp.org
Subject: Re: [Greenbuilding] Advanced Framing/OVE in Midwest?

Jason Stone and Ronald Cascio wrote:
> ----- Original Message -----
> From: "Jason Stone"
>
>  We use panelized 2x6 16" o.c. construction one some of our homes and 
> are very pleased with the result, though we end up using more lumber 
> than we'd like. The timing of your post is interesting since I was 
> researching OVE this week to see if we couldn't reduce our material 
> usage.  Has anyone else actually built with advance framing techniques --
in particular 2x6 with 24"
> o.c. in the Midwest?  I've run into polite resistance from my 
> engineer, green reviewers, architect, and carpenters because of 
> concerns about structural intergrity (specifically, what I understand 
> to be a 90 MPH wind rating requirement, which in turn requires a high 
> cost sheathing that offsets any OVE savings).
>
>  Jason Stone
> Sage Homebuilders, LLC
> St. Louis, MO
>
>
> We've been using 2x6 - 24" o.c. for I can't remember how long. We use 
> polyurethane to glue all of the sheating to the studs, walls and roof.
2x6 on 24" spacing is in the International Building Code standards, so I
can't understand why anyone would be resisting the system.
In B.C. we can only use the 2x6 construction for exterior walls, but spacing
varies depending on point load requirements. A lot of the newer construction
I've been working on pretty much looks like what is recommended in the
Advanced Framing guides--except that we still used doubled top plates on
walls.
The extra stud cavity depth is required to get the minimum required
insulation levels in.
I haven't seen anyone glue the sheeting on, though. If you're concerned
about off-gassing from the glue, you could skip the glue and use the new
Hurriquake fasteners from Bostich/ Stanley, which are specially designed to
withstand high wind and earthquake loads.
http://www.bostitch.com/xhtml/interactive_hurriquake/hurriquake_show.html
These nails don't appear to add that much more cost to a project over using
ordinary air-nail spikes, especially if you're skipping the glue.

With occasional 90MPH wind loads, I'd think you'd also want to build using
hurricane fasteners  to tie the roof trusses to the footings, "just in case.
"

If you're building the wall assemblies on the floor and raising them you can
also inset metal t-braces into the studs by cutting a diagonal slot for them
with the circular saw then nailing things together before you fasten the
sheathing.
With care, this will also help keep the wall assembly square as you raise
it, so the extra time it takes to add the bracing should lessen the time
spent squaring things up when the wall panel is raised.

With the deeper cavities, you could use Roxul rockwool insulation batts and
end up with about R-22.5 in the walls. The rockwool also has some other
advantages--the stiffer batts won't sag if they do get wet, and don't seem
to promote mold grow on them like fiberglass does.  Local availability from
your suppliers might be a problem, though.

There's an Advance Wall Framing guide available at this link and it's worth
looking at, and forwarding to the naysayers:
<www.eere.energy.gov/buildings/info/documents/pdfs/26449.pdf>http://www.eere
.energy.gov/buildings/info/documents/pdfs/26449.pdf

I think there was also at least one article about this in Fine Homebuilding
some years ago.
> <snip>
>
> Stick to your guns, don't let those who are stuck in their old ways 
> take you down with them.
>   
Agreed.

Cheers,

Chris Green.

_______________________________________________
Greenbuilding email list
List info:
http://listserv.repp.org/mailman/listinfo/greenbuilding_listserv.repp.org
List email: Greenbuilding at listserv.repp.org Managed by BuildingGreen, Inc.
http://www.buildinggreen.com
      publisher of Environmental Building News and GreenSpec(r) Hosted and
archived by REPP / CREST http://www.crest.org