It was a rough start to our initial rough-in blower door test with an initial test result of 0.66 air changes per hour at 50 pascals. Our air tightness goal for the rough-in blower door test result was 0.30 air changes per hour at 50 pascals. So the students and Fowler and Hammer went to work on finding air leaks and sealing air infiltration with OSI Green Series Draft and Acoustical Sealant caulk and Siga Wigluv tape. The temperature in the SwiPHt was 65° F. And after the internal heat gain of 5 students air sealing, the temperature went up to 73° F. Since the air leakage rate was so low, we had to switch to the smaller fan unit that is usually only used for testing ducts. After the I SPY and Seal game, we were able to get the air changes per hour down to .44. Phew! Now that is a tight, comfortable house.
By Genevieve Mortenson, 2nd year Building Systems Technology Student
The roofing framing has been completed for several weeks, now. But, progress will be made soon on the roof covering. We wanted to chat a little about some of the details unique to our roof system.
The roof features a 12/12 pitch resulting in a 45 degree roof angle. This will optimize the potential energy gains for a Photovoltaic array for our location and latitude. The trusses are spaced 24” on center, demonstrating the “stacked” framing technique that allows us to utilize single top plates in our wall framing, meaning that less lumber is used. The roof is sheeted with 3/4” plywood and covered with a peel and stick ice and water shield. It will feature a standing seam, steel roof covering with matching gutters. The roof is designed with longevity and durability in mind—steel roofs last for 50 to sometimes 75 years without any, or minimal, maintenance. Also of interest on our roof will be a solar thermal panel that will pre-heat our domestic hot water supply. This will be installed after the standing seam steel roof is installed.
This house doesn’t just take the walls, roof, and slab to the next level with air sealing and insulation. It takes it to a whole other level with robust windows from OptiwinTM. These are higher-performing windows that have a U factor of .125 (R-value of 8)
During our Passive House workshop, students, faculty and community members watched as students carefully installed a standard window into a standard construction wall. Then, we went to the passive house site and watched as Fowler and Hammer installed the extremely-robust windows into the SwiPHt house. Students from the Architectural Technology, Wood Tech, and the Building Systems Technology programs came to see these extraordinary triple pane high performance windows being installed and were amazed to say the least. There was not much of a difference from installing a double hung window into a standard construction wall to installing these aggressive passive windows. The most impressive part was these windows have well-insulated frames and are installed in the middle of the wall as part of the assembly, keeping them safer from the elements and reducing thermal bridging even further. These windows are truly impressive.
By Josh Martell, 2nd Year Building Systems Technology Student
With the progress of the SwiPHt house moving right along, Fowler and Hammer are making tremendous strides. The inner framing of the house has taken shape. This inner 2×6 advanced framed wall features 24 inch centers and a single top plate. This reduces a large amount of lumber when compared to standard practices.
With this framing in place, we can start to see the differences that make this house stand apart from the other homes in the La Crosse area. With an air tight, thermal bridge free, and insulated wall thickness of 22 inches, it is easy to see the passive house standard in practice.
As progress continues, the building is going to be made more robust. Below we can see the roof trusses in place—with a 24 inch energy heel to allow for maximum insulation over the top plates of the second story wall assembly. Please stay tuned to see the house take shape!!
November 4th – 8th 2013.
By John Kroll (2nd year Building Systems Technology Student)
After weeks of anticipation, our mental images of the Passive House project on the 24th St lot are finally starting to visualize above the ground.
Construction has just about finished around the basement exterior this week after the dimple membrane was put in place to allow a water drainage plane and to prevent capillary action. The area was then backfilled with the mound of sand that was next to the lot to finish the phase.
Above grade, the main floor trusses were installed and we are now seeing the first walls being constructed to give us a visual of the size and scope of the home and how it will sit within the neighborhood. One aspect of a passive house is the notion of “less is more” when it comes to the wall studs. With 24″ on-center spacing, the wall studs will lessen thermal bridging and also lower material costs in the same process.
As a Building Systems Technology program student, we talk about the science of buildings daily in our classes. But finally being able to see the science in action on an actual construction site provides us something more powerful than our class lessons cannot replicate: in-the-field experience. I cannot wait to see this home in a few weeks when it is encased from the elements – and our approaching cold weather!
The site is being backfilled while the dimple membrane is being installed.
The walls are starting to go up on the passive house with 24” on-center wall stud spacing.
By Marion “Bob” Carlson, 2nd year Building Systems Technology Student
The first of three SwiPHt Passive Houses is “swiftly” moving along. Thanks to solid planning from Western’s coordinators and instructors, the design firm Intep, and general contractor Fowler and Hammer, the house is making good progress.
For hands-on learning Western Technical College is able to give their students a unique opportunity, because this is the first time three certified passive houses will be built right next to one another—at least in the United States.
As a second-year student, I am finding this a very valuable learning experience and would like to thank my instructors from Western on the good job that they are doing by incorporating this project into our course material. Our class for Architectural Building Information Management has learned a lot along the lines of properly documenting the building process for different types of certification like Green Star.
With the foundation completely insulated the slab has been poured.
With the basement wall poured and set, the forms are now taken down for the next step of treating the walls and the nine inches of insulation will be applied.
Authored by Josh Martell and Ben Heyer, Building Systems Technology 2nd year students
Since the official ground breaking of Western Technical College’s SwiPHt Passive House, progress has really been made. Hess excavation has generously donated their time, and professional experience to provide excavation and site preparation. Fowler and Hammer were also able to start with the home’s foundation and flooring by creating the footing of the home. They also began some of the home’s “mighty” insulation process by laying 9” of extruded polystyrene under the 5” cement slab floor. Separating the cement from the insulation below is 2 layers of 6mil polyethylene membrane. This layer will act as an air, vapor, and water barrier.
Passive radon vents and drains were installed around the home’s perimeter to reduce the chance of this natural gas entering the dwelling, improving the indoor air quality. All plumbing protrusions into the home’s envelope have been diligently taped and sealed to reduce the heat loss and prevent moisture intrusion. The home’s foundation floor and walls will be anchored together for structural support every 16” on center with structural rebar. This is where the next week of building will begin with the pouring of the concrete walls. Stay tuned La Crosse as Western’s SwiPHt” House project is coming together quickly.