Archive for the ‘Energy efficient’ Category

Don’t miss the Eco Building Guild’s South Sound Green Tour this weekend, April 16th and 17th. All sites are open from 10:00 am to 4:00 pm.  There is also a Expo at the Lott building behind Alpine Experience.  Come see all the wonderful site and vendors. Look in Friday’s Olympian for the insert with all the information.  We are featuring the Hobbit House this year. Come out and see the round door. The address is 10621 Katie Ann Lane. Follow the signs from Steadman Rd. Turn on to 103rd and then on to Katie Ann Lane. Hope to see you there.

It was very exciting yesterday to attend the 2nd annual regional meeting of Passive House Northwest held at Evergreen State College. Last year at the 1st one, we had about eighty people attend. This year my guess would be well over three hundred. This didn’t surprise me because the movement is really picking up steam in the US. And why not, who doesn’t want to live in incredible comfort, have a home with minimal carbon foot print, as save a ton of money in the process. And because they are so energy efficient they only require about a quarter of the solar panels of a code built home, to supply all of you energy needs. Imagine never haveing to pay a power bill again.

The conference featured several talks on methodology, along with case studies of actual homes that have been built in the northwest. The speakers ranged from building scientist, builders and passive house consultants, to even the home owners of Passive House’s.  The talks were very detailed, and incredibly informative. Also there where many vendors promoting the latest advances in things like windows, Heat Recovery Ventilators and air sealing tapes and fabrics.   For me the most telling reason of why this is the right approach to home building was hearing  the home owners, the folks who actually paid for and live in the homes, explaining how wonderful there new homes where.

I celebrated having attended the conference by meeting with my design team and the homeowners of what will become our first Passive House. We settled on a floor plan and will meet at the Patterson Lake site next week to review elevations and exactly how the home will sit on the sight. It very exciting and I will try to keep you updated as we move through the process.

In the last posting I started the conversation about Air Sealing walls. The idea of air sealing is simple enough, the more air you prevent from leaking through the walls, the less your home will feel drafty. The less drafty, the more comfortable your house will feel and the less energy it will take to maintain the temperature of the home. The best way we have found to do this is to air seal on the inside of the wall or right behind the sheetrock. By sealing the wall at this point, we are still able to build a wall that can allow moisture to escape to the exterior side of the wall.

So how do we do it. One method is to use plywood or OSB on inside of all exterior walls, floors and ceiling joist. Then using tape we seal all the joints and seams were the individual sheets of plywood meet. We then fir out the ceiling and walls to allow for all of the electrical wiring and HVAC duct work. We design the plumbing so its on the interior walls as much as possible. This does add to both the framing materials and labor, and has to be accounted for in the budget. In the design we strive to have as few of penetrations in our air seal as possible. Each penetration is taped to prevent air leaking past. I know this sounds like a lot of extra work, and it is, however the long term payback will more then offset this cost, and remember the home will feel much more comfortable.

The tape we use is from SIGA. (http://www.siga.ch/Home.20.0.html?&no_cache=1&L=1) remember to hit the english button on the right of the home page..They are a company in Switzerland, who have been involved in air sealing for many years. They have fabrics and tapes for all kinds of air sealing. Their American distributor is The Small Planet Workshop. (http://www.smallplanetworkshop.com) locate right here in Thurston County in the Oyster Bay area.

It has long been known that without making your home air tight, there is no way for your insulation to perform at it true r value. For example if your walls are built with 2 X 6 studs and insulated with R-21 insulation batts, without the house being airtight, the insulation performs at a reduced R value, something around a R-17. This is caused by gaps between the studs and the insulation which allow air to leak by. The problem in the past with making a home air tight was that the process would also trap moisture in the walls, which would lead to dry rot. Back in the 80′s and early 90′s air tightness was tried by installing 6 mil. plastic on the studs and drywalling over it. With plywood or OSB on the exterior of the wall, this left no place for the water to escape. I remember walking into houses before the drywall was installed and watching the water run down the sheets of plastic. This method of air sealing was quickly dropped and no real alternative was offered. Some minor air sealing of the bottom wall plate to the floor with caulk and foaming around doors and windows is about as far as we’ve gotten with the codes.

Just this year Washington state has adopted a stricter insulation code. It is basically the old Energy Star standards. One part of the code is the requirement that all new home have a blower door test prior to final inspection. Blower door test measures the amount of air leaks a home has. New homes are required to have a blower door score of 7.5 or lower. What this means is that if the air pressure difference between the outdoors and the inside of your house is 50 pascals (50 pound per square inch) then the air in your house will completely exchange itself seven and one half times in an hour. This is still a drafty house but its a start.

By making homes airtight we obviously can cut down the cost of heating these homes. Done correctly we also can build the walls in a manor that will allow moisture to escape. This is the best way to build. In future articles I will talk more about the methods behind this type of construction

The Eco Builders Guild, South Sound chapter is proud to announce the second annual South Sound Green Tour coming April 16th & 17th. We started the Green Tour last year and it was huge success. Just like last year, we will feature houses and commercial sites that represent the best in green building and sustainable practices. The homes are located through out Thurston County, including Tumwater, Olympia, and Lacey. We will also have workshops at each site demonstrating many of the features of each site. This year we have also added an expo which will be located in the new Lott buildings parking lot. It will house lots of vendors offering a huge array of green products and services.

Another big addition to the tour is that the Seattle chapter has joined in with us and will have a tour of their own on the same weekend. For more information, or if you would like to be a vendor or site sponsor please visit http://www.ecobuilding.org/events/2011-green-home-tour.