Posts Tagged ‘Energy efficient’
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
Laupen homes LLC. is proud to showcase two homes in the OMB tour of Homes. First we will feature the Cooper home. This is the same home we had in last spring’s Green Tour. If you didn’t get a chance to see it the first time, come out this weekend and be amazed. This home was a challenge to say the least, but we persisted and the outcome is incredible. You can view photos of it on our project page and read the owners comments on our referral page.
The second home we are featuring is the Bouvier/Rogers house, also known as the hobbit house. Now we could really call it a hobbit house without a round door, so a round door it has. Handcrafted out of mahogany wood, the door has a tree carved into it. Master carpenter Mike Anderson was the inspiration behind the door. It is a must see. This home also features a “Floating Loft” over the main entrance and living room. With lots of curves and whimsical features this home is a must see.
But don’t let the playfulness of the home fool you. It has state of the art energy efficient systems including radiant heat and a Heat Recovery Ventilator. Six operable ski lights make for wonderful natural lighting and at the same time allow the summer heat to escape keeping the interior of the home cool without the need for air conditioning. The outstanding blower door score of 1.23, (most new homes receive a 5 or higher) made it easier to received a Built Green level 5, and Energy star certifications.
Come out this weekend and see these wonderful homes. I look forward to meeting you
How you maintain your garden is also as important as planning when it comes to conserving water. If you’re looking at limiting the amount of water you put into your garden, you will also need to limit the amount of water that flows out of your garden. You can do this is many ways:
• Pick plants, shrubs and grass that are known to develop good root systems and employ gardening techniques that improve roots. One way to do this is to mow the lawn tall, but do it frequently. The other way to do it is to pick plants that go well with your climate and soil and water them well for the first few weeks before you reduce the frequency. Keep looking out for leaves that go yellow and new shoots that look weak and pale.
• Mulching is an excellent way to ensure that your soil remain well hydrated and does not loose moisture, especially if you live in dry weather. Mulch can be conveniently prepared in your backyard using organic waste from your kitchen. A healthy dose of nitrogen fertiliser is also recommended, provided you know what you’re doing.
• Irrigation techniques are the most crucial aspect of conserving water in the backyard. In regions frequent watering is required most homeowners opt for irrigation to keep it convenient. Drip irrigation saves much more water than sprinklers which water a lot of things other than the grass. Gray water systems are another great option. Gray water is ‘wash water’ i.e. water used in the bathrooms, kitchen sinks and laundry, which is treated and then used in gardens. Gray water does not include water from toilets (which is called black water) and is perfectly safe, with few chemicals and pathogens once it’s treated and is used by a large number of families for irrigation. A gray water system is simple enough to be installed in your backyard. However, make sure you are familiar with your locality’s policies on gray water systems.