A community of timber home enthusiasts and those who love energy-efficient homes

Where to begin with timber framing

In order to build the best envelope possible in order to get to "net zero energy" houses some day the first place to begin is to incorporate Insulated Concrete Forms (ICFs) into the basement or crawl space foundation. With the addition of SIPs (Structural Insulated Panels) a builder is well on the way to building a house that is totally off of the grid or selling energy back to the electical power company someday. Utilization of Low E glass, building orientation, Energy Star rated appliances, flourescent or LED lights. A geothermal or other super energy efficient HVAC system should be incorporated into net zero energy homes also. Ultimately when the next generation of Photovoltaic solar cells become readily available at a sustainable price and or wind generators make the next leap foreward in terms of energy efficiency we will then be able to build the nearly perfect home which creates more energy than it uses. Paul Zumfelde Riverbend Timber Framing

▶ Reply to This

Replies to This Discussion

Permalink Reply by Wes Loder on July 17, 2009 at 10:14am

The problem with ICFs is that they provide no thermal mass, an essential component of any passive-solar building. We did not use ICFs in our passive solar house for that reason. Straw bale construction has the same short-coming. Instead, we used 12 inch block filled with grout as part of the solar mass. These walls, in turn, are insulated on the outside with four inches of blue board plus slabshield that wraps the entire basement structure. Works nicely. ICFs could work, if there is an alternative source of mass in a passive solar structure. WES LODER

▶ Reply

Permalink Reply by Wes Loder on August 7, 2009 at 9:37am

We recently completed our Energy Star rating. House scored 50 on a scale of 0-500 for a 5+Star rating. Essentially as good as it gets. We are pleased. House is so tight that the blower test could only get to 205 CFM compared to a "normal" of around 3500. The rater asked us what we do for fresh air. We answered "open a window." Kinda' old-fashioned but sure takes less energy than something that uses a motor. WES LODER

BTW, in reference to my earlier comment. The block walls are only in the basement. The timber frame part uses SIPSs.

▶ Reply

Permalink Reply by Paul zumFelde on October 2, 2009 at 10:58pm

Wes You are right about not having thermal mass in ICF and SIPs home like I had in my first homemade passive solar thermal envelope timber frame house built in 1978 but since they sit side by side on my fathers family compound in Northwest Ohio I can continue to monitor the energy efficiency of both houses and the SIP house wins hands down. For thermal mass in my original house I had a concrete block wall on the southfacing wall in the greenhouse and 28 tons of rock under the crawl space in the basement. The problem with that house even though there was a double envelope totally surrounding the inner house on all sides except the east and west was the thermal bridging that occurs with fiberglass batt insulation placed between 2x6 stud walls at 16 inches on center. At that time it was considered a superinsulated house but would not measure up to todays standards.
My house measured 829 CFM according to blower door tests conducted by the local electric co-op. Paul Zumfelde

▶ Reply

Permalink Reply by Joanna Asha Demkow on September 21, 2009 at 11:34am

Hi Paul,
Is the prefabricated timber frame technology popular in the USA? Do you know any companies specializing in that type of timber construction and energy effcient technology in the USA.
Many thanks
ashademkow@yahoo.com
Asha

▶ Reply

Permalink Reply by Paul zumFelde on October 2, 2009 at 11:21pm

Joanna Is prefab timber frame technology popular in the USA? No since it represents less than 2% of all new home construction in the USA but what is becoming very popular among cutting edge builders in the use of Insulated Concrete Forms (ICFs) and Structural Insulated Panels (SIPs) for "Green" building. Whole houses could be built of ICFs and SIPs without the timbers but utilizing timber framing greatly reduces the amount of wood used in a house and creates soaring "psychological" spaces that greatly enhance the joy of life.
Riverbend Timber Framing out of Blissfield, Michigan is one of only a few North American companies that has a design studio, sells ICFs and SIPs (made by the parent company) and also offers custom timbers cut to precision so the SIPs panels fit perfectly.
My house of slightly more than 5000 livable square feet will use about $900.00 to heat and cool the entire house for one year. It is used as a residence for my wife and I and my 90 year old parents and is visited daily by two grandsons and daughter and son in law as I or my parents provide grandchild care on an allmost daily basis Paul Zumfelde

▶ Reply

Permalink Reply by Bonnie Pickartz on November 23, 2009 at 9:54am

Begin with an efficient plan. Think through how you live and how your house will be used.

The design should work well on your site and include site appropriate windows, overhangs, and foundation. The plan should specify an energy efficient enclosure (typically insulated panels) and windows.

We just built our new home (and blogged the construction and habitation at Building A Timber Frame . It is energy efficient and lives well.

And however you build, Build Boldly

▶ Reply

Permalink Reply by John M. Perrott on March 16, 2010 at 10:16am

Here in Florida, I have had to do things a bit differently due to weather, humidity, and insects. I am using cypress for the frame, which I know isn't the greatest choice with regards to structural strength, but helps with my humidity and insect infestation problem. I have also incorporated ICF's to surround the frame (using a little "gizmo" of my own invention) which then solves my structural problem. All this together with energy efficient, impact resistant windows gives a superior home in terms of both structural integrity and energy efficiency. Add a ground source heat pump for my Heat/AC needs, and I am about as "green" as can be with regards to what is available on todays market. I am hopefull that photovoltaic panels come down in price relatively quickly so that I can incorporate them in all future homes as well.

▶ Reply

Permalink Reply by Jim LaFrom on January 23, 2012 at 2:08pm

Paul,

I am looking into the whole Passiv Haus concept with a Timber Framed house in the LakeTahoe Area of California. My greatest interest has been Passive solar but that was before this 'net zero energy' thing started to get more air play. My questions are:

Is it necessary to consider this any more, when air sealing and superinsulation seems to accomplish the same thing with less glazing? In terms of resale value, I'm thinking that to avoid the 'oddness of massive solar glazing' would be a benefit. The reason why I' saying this is that when looking for homes and home sites is that the Realtors would tell us that most solar structures fail or are about to fail due to leakage in the roof glazing. I must say I did see quite a bit of this in the unoccupied homes. I don't know if this is just a design and craftsmenship flaw or just that the building movement through the extremes of temperature ranges doesn't handle this well over time.
I would still consider it, if it still added value and could do it, design wise, without it screaming "SOLAR ODDBALL".
If I'm starting from scratch, would you recommend an architect or design focused on solar and work to adapt it to work with a Timber Frame concept, or try to use an existing Timber frame design or architect and add/modify the structure to get the passive solar element ? Do the TimberFrame home manufacturers themselves work with this much? I haven't seen many plans that try to incorporate this.
If I'm building in a zone where the temperature range lows could go to -10 and see rare highs in the summer of 85 degrees, Could I eliminate the isolation of the thermal mass room, as I doubt if it would ever over heat in the summer? I guess the other consideration would be the minimizing the cooling effect at night by closing the doors off into the 'solarium'.
Another consideration would be that I would be using a hydronic heating system. So the floor temparature in the solarium could be maintained over night.
If you know of any existing designs that tastefully incorporate passive solar glazing?

▶ Reply

Permalink Reply by Judd Dickey on January 23, 2012 at 4:53pm

Jim, these days, a well functioning house incorporating some passive solar, good insulation, and good infiltration barriers will cut your heating costs in half without appearing to be a solar machine. A typical well constructed SIP house on an ICF or other well insulated concrete foundation will save much energy. If you can keep the house nice and warm during the day without heating, then a little heating at night does not upset the balance of nature.

Also, I have found that the cost of heating with a hydronic floor is not less expensive to operate, but rather is used because it is a nicer quality of heat, without a lot of sound and drafts. Even so, you will need interior fans to prevent pockets of moist air from forming, and a ventilation system (air to air exchanger).

If you design the house to frame your views to the outside, and balance the elevations on the outside, you will do fine. You can increase or reduce the passive solar gain with roof overhangs and proper orientaion. These basics of passive solar suit many design styles.

In the Lake Tahoe area, half the battle is to not overheat in the summer, while catching quality light in the winter. I avoid roof glazing other than a few well placed skylights for the purpose of lighting otherwise dark interior spaces, saving power. Judd Dickey, Architect

▶ Reply

Permalink Reply by Bonnie Pickartz on January 23, 2012 at 5:04pm

Jim, Judd is right on target.

A home should be designed to live well and to sit well on the site. Then incorporate appropriate energy saving technology/design into your home. You'll end up with a home that is comfortable, efficient, and beautiful.