November 23, 2009
We have accomplished a lot of work in the last month and a half and the time has come for the blower door test. The blower door test will measure how tight the home was constructed by measuring the air flow through the blower door when the house is place under negative pressure.
To be ENERGY STAR rated we needed to achieve no more than 1900 cfms, but WPPI Energy wanted 612 cfms. So, we invited all the subcontractor and ENERGY STAR inspectors to show up for the inspection so we could learn more about building air tight homes.
As we started the blower door test I actually became very nervous for myself and the subcontractors that put so much effort into this project. As we all stood there quietly we hear Joe Nagan yell out "oh, it's tight." We achieved something that we all should be proud of, and this could have not of been done without quality subcontractors that care about doing a quality job.
We have made ordinary building extraordinary with subcontractors who care about our home owners and their desire to build a net zero energy home. We achieved 351 cfms with the help of everyone. Thank you!
September 21, 2009
Drywall is going up!
This is another team effort from our drywall hangers to make sure that the vapor barrier does not get damaged. They had to hand cut all the drywall on the ceiling and the exterior walls to ensure that no vapor barriers were not over cut. After all the drywall was installed I caulked all the outlets and window jams to the drywall to again create an air tight seal.
September 21, 2009
Who would have known that insulating a can light could be so complicated? We completely enclosed the entire can light so there was no chance of air infiltration. We used 1" foam with all the seams taped and foamed to create a unbelievable tight seal.
September 21, 2009
We didn't stop with the walls, we took it all the way to the top! The attic was another important area for air sealing. We sealed all the top plates and all penetrations that came through the attic. You can see that we used spray foam again to create a superior air seal. When you look at the picture you can see a foam shoot that is stapled to the bottom side of the roof. This is called a proper vent and this allows air to travel from your exterior soffit to the attic. Believe it or not we want the attic to stay cold in the winter. This helps with moisture control and ice daming by moving the air in that area. We want that attic to stay cold! We utilized the foam to hold the proper vent in place and create another air seal at the top plate of the exterior wall.
September 13, 2009
I have talked a lot about the building shell and the importance of having an air tight home. When you look at a home, the most vulnerable areas for air infiltration would be at the box sill. The box sill is located on the outside wall where your floor system meets the outside wall. It is impossible to use standard practices with fiberglass batts to create a air tight system. That is why we use 3" of spray foam insulation in all the box sills. The foam is a closed cell foam which does not allow water and air molecules to transfer through the foam. It is also recognized as a vapor barrier so plastic does not need to be applied over that area.
In the lower level of the home we spray the box sill with foam and carry that foam over the treated 2 x 6 sill and onto the concrete. This creates a complete seal from your framing to your foundation wall.
This can also be done in existing homes if your lower level is not finished. This is a great way to make your existing home more energy efficient.
September 8, 2009
Insulation can be one of the biggest home improvements that you can do on your existing home and your new home to make it more energy efficient. In the Scheller home we chose to do a insulation system called BIBS.
A more technical name for this may be Optima Fiberglass, but we choose to call it BIBS for installation reasons. We first seal all the exterior sheathing to the stud with a bead of foam insulation. This helps ensure the possibility of any air infiltration. The second thing we do is put a breathable netting over the stud that is pulled tight and stapled every half inch or so. This why it is called BIBS! We then blow that stud cavity full of fiberglass insulation to a recommend density that will achieve an R-23 value in a 2 x 6 wall.
September 3, 2009
It looks like a can light, it feels like a can light and it is. One of the major requirements when we started the Green Max Home was that we could not use any incandescent light fixtures. So, we looked at fluorescent and we didn't care for the dimming options that you are limited to. We then looked at LED lighting and there were no restrictions on dimming. This was a huge plus for the Schellers and the Green Max Home electrical use.
Electrical Solutions is installing a actual standard 6" Halo can that is not any different than most us have in our homes. If you have a 6" Halo can in your home now you can do the same thing that the Scheller's are doing in their home. What makes the can a LED is a transformer and light that screws into where the normal incandescent light would be mounted. Simple!
Here's even more good news about LEDs, they consume 75% less energy than a 65 watt incandescent light bulb. Which means that if you have 65 watt incandescent light bulb a LED light will only use 15 watts. The other good news is that it last 5 times longer and will last up to 50,000 hours, which is 50 times longer than a incandescent light.
August 28, 2009
This is not your ordinary electrical box! What we are using on the exterior wall and our 2nd floor ceilings are electrical boxes with a pliable rubber gasket. This works as a great wall seal between our drywall and the electrical box.
Once the drywall is installed we will then caulk the electrical box to the drywall. When we inuslate the exterior wall we will foam the complete back side of the electrical box with a closed cell foam. This will seal all the wire pentrations that enter throught the back side of the box.
August 24, 2009
With the Green Max Home we took into account efficiency and comfort ability and that's why the Scheller's decided to have three different zones in the home. This will allow them to control the temperature on all three different levels of the home. Our subcontractors did a EXCELLENT JOB working together sharing all the interior wall stud cavities for all the mechanicals.
I have talked a lot about the sealing of the exterior walls and the building envelope and this is the same for the interior of the home. Dave Jones Heating and Cooling went the extra mile to make sure that all the duct work was sealed with tape and caulk duct sealant. The main purpose for this is to make sure that we do not have energy escaping out of the duct work and that energy is going directly to that register that is calling for heating and cooling.
August 15, 2009
On the outside of the home we used DOW rigid foam that has a r-value of 5. This is important because it insulates the outside of our stud wall. This will help with the transfer of cold through the actual 2x6 stud.
Have you ever seen a home on a cool morning and you can see ever stud cavity? What you are actually seeing is the stud being warmer than the stud cavity and the frost is melting in that area. What we are trying to do is create a balance in that stud cavity so we don't have condensation forming when we reach the critical dew point. With the stud being warm and the cavity being cold this is a perfect situation for this to happen.
Before we install the windows we will wrap the entire home in Tyvek house wrap. The Tyvek house wrap will stop any wind or water molecules from penetrating through our building envelope.
August 6, 2009
One of the major requirements with the net zero home was the use of the (PV) electric solar. The concept is very simple in my description. The solar panels track the sun from sun up to sun down with a photo eye. Inside the home we do not have batteries lined up, but instead the power produced goes directly back into the electrical grid. The power used is bought at 9 cents per kWh and power produced is paid back at a rate of 30 cents per kWh.
I have to admit that when we started this I questioned (PV) electric solar, but after the panels went in it really motivated me. I started doing things different at home and in our office. I believe that the opportunity is huge for (PV) electric solar and I can't wait to see the solar panels dancing with the sun.
July 25, 2009
The geothermal was installed with ideal soils. When we install the geothermal we want it to be as wet as possible, and we hit the jackpot.
The geo loop installers were not liking the conditions, but the Scheller's will be singing all the way to the bank with the return on their investment.
The water and the sandy rocky soils help make the best soil contact to the geo loop and the transfer of energy to the geo loop system or out of the geo loop system.
We also installed soil temperature sensors that will monitor the soil temperatures 2 feet, 4 feet and 50 feet out from the geo trench. This will help us monitor the soil temperatures which in turn will tell us how much energy we are using from the geo field.
July 21, 2009
Under the concrete slab in the lower level we stepped it up another notch. We installed 6 Mill plastic with all the seems taped to act as a moisture barrier between our 4" of gravel and lower level concrete slab. This barrier will perform two things for us as a moisture barrier and a vapor seal for our radon gas. This will force all radon gas and moisture to the drain tile and not through the lower level slab.
To ensure that the net zero home was insulated on all six sides we installed 2" R-10 foam on top of the plastic. We taped all seams and we put Great Stuff expandable foam around all penetrations. We also install 1/2" R-5 foam on all the footings and up the wall. This 1/2" foam acted as our thermal break between the foundation wall and lower level slab.
July 20, 2009
Energy efficiency starts from the outside in. On the outside of the foundation walls we installed 2" R-10 foam two feet down from the top of our foundation. Studies have shown that exposed concrete will heat up and wick up moisture when exposed to the sun. With the 2" R-10 foam on the exterior of the foundation this will stop the concrete from heating up and sucking up that moisture. It will also help us in areas where the sun is not exposed to the concrete to keep it a more consistant tempature.
Under the 2" R-10 foam we installed a product call Tuff-n-Dry. This product is applied over a tar coating that is sprayed onto the concrete and footing. The Tuff-n-Dry product has a R-Value of 5 per inch, and we installed 2" of the Tuff-n-Dry product for a total of R-10. This product acts as a drainage board against our foundation by allowing the water to pass through the product to the drain tile located on the outside of the footing. The other great feature of this product is that it gives us a 30 year dry basement warranty.
It is very important in our net zero home that no moisture enters through our building envelope whether it be through the 2x6 wall or a 8" concrete wall.
July 15, 2009
Who would have known that a footing and drain tile could be so important in the energy efficiency of your home? When we designed the building envelope of the home we took into account the footings and keeping them dry with drain tile on the inside and the outside of the footing. You may be asking why this is any different than any other home and my answer to that would be the functions that drain tile performs. It serves three purposes in the design of the home.
- We installed 4" of clear stone under the entire lower level slab and footings to allow the moisture and air to move freely under the house.
- We installed 4" sleeves in all the footings to allow 3" corrugated pipe to pass through the footing for easy flow.
- We installed an active radon system that will perform two things for us - removal of any harmful radon gas and removal of moisture under the home through the drain tile system.
All these functions of our drain tile system will keep our lower level dry so we don't have to run a dehumidifier and remove any harmful radon gas.
