Thursday, November 26, 2009

Framing, Insulation, and Solar

As mentioned in an earlier post, we had looked at many new alternative materials for framing. ICFs, SIPs, and pre-fab were really interesting and had many advantages. We really wanted steel framing and had looked at companies that provide steel frame kits. A company nearby in Georgetown, Transcon Steel, fabricates steel panel systems. These would have been great to use and we got a bid from them that was very reasonable.

Since we're building on a steep lot, the retaining walls and site prep add significantly to the cost of the home. The local Jonestown ordinance requires a two car garage. As you can imagine, it requires a lot of concrete to support a structure on a 38% grade. And, the driveway can only be 12-15%, so quite a bit of the budget goes toward that as well. We tried to get a variance to avoid having to build the garage, but were turned down. So, with the added cost of the garage itself and the concrete to retain it, it looks like we'll have to go with conventional stick-built construction.

Even stick-built can be "greened." Our builder, Don, has specified finger jointed studs, which are made from shorter pieces of wood glued together. They make use of lumber that might otherwise be wasted and they tend to not warp like conventional studs. The Austin Green Building website has more information. Don also orders carefully to avoid as much waste as possible.

For a tight envelope, the walls will have 3.5" of sprayed foam insulation. The floor will be partly slab and partly on pier and beam, which will also be insulated. The Attic will be completely insulated with 5.5" of foam. This insulation allows the air conditioning to be more efficient with ducts running in air conditioned space instead of in a 140 degree solar oven. The metal roof will reflect heat and provide a good surface for rainwater collection.

We plan for a small solar photo-voltaic installation, a little over 3Kw. And, if the budget allows, we'd like to have a wind turbine as well. More details on these systems later.


  1. I’d agree that steel framing has come a long way and has many more benefits then traditional wooden framing.

    The versatility of this steel studs, steel purlins and other steel building and construction components makes it easier to decide what direction to go. I’ve found some interesting articles on the same topic at Industrial Machinery News (http://www.industrial-machinery-news) where they showcase some of the equipment (roll forming machines) used to manufacture these products.


  2. "Transcon steel" - whether Sushchesvuet ткая the company.?
    Never heard...

  3. Check out their website. They are local here in Texas.

  4. Sorry, the website is: