Week_11
Blog Post Week 11: Kitchen, bathrooms, exterior boxes and more...
This week was mainly about finishing the exterior front porch benches, reconfiguring the kitchens due to a construction configuration that ignored the original kitchen design, and other finishing work inside the units. We also did a third and final Blower Door test.
10/30/2018 - Day 16
We started the day by sealing off the newly installed front doors of the two units. We had to seal the space between the door and the wall so that the building envelope would be air tight. Later in the day we did a blower door test to make sure the envelope was as air tight as it needed to be. The results were still disappointing - we only got to a value of 629 CFM at 50 pascal, which equals 3.2 air changes per hour. The original goal has been less than 200 CFM or better than 1 air change per hour. The considerably lower performance can be traced back to specific construction decisions that ignored the original specifications and design. The lessons to learn from this is that even a little deviation from a specified methodology and specified plans, in sum, can harm a carefully designed building to a point where a promise can't be kept anymore.
Air Infiltration Rate
Excel Spreadsheet that allows the calculation of Air Changes per Hour based on the building's area and volume. This screen shot shows the result after weeks of additional work, in which the team tried to fix construction mistakes that had been made before we were brought onto the project. One major issues are the windows, which were not to specification and leak air throughout their entire frame system, even when tightly closed.
Blower Door Test
Compared to the very first Blower Door test with results of 1044 CFM, the team was able to reduce the overall air infiltration rate to 629 CFM, which is 40% better. Anyhow, the target value was to be better than 200 CFM, to guarantee the building's performance with regard to the chosen systems. In a worse case scenario, the chosen heating and cooling systems will not be powerful enough to fight the additional heat loss.
For the passive strategies of the house to work it is important for all of the conditioned air to stay within the house, and not escape through cracks in the house. For the rest of the day some of us worked on installing light fixtures in the interior of the house. Others continued to work on the box benches for the units from the week before.
- Zachary Heslop, Jörg Rügemer
11/01/2018 - Day 17
We definitely felt the change in temperature as the weather turns colder and we experienced the need for jackets today. We split up into two team today. Scot, Daniel, Andy, Chris, and Joe worked on finishing the exterior redwood box in front of Unit 10. This particular box was a little more difficult than the first because it was initially built by others and needed to be squared up and plumbed more accurately. After spending some time on correcting the frame, we were able to complete the box including the hinged lid.
David, Mitch, and Zach worked on rerouting the utilities that go to the fridge and stove. The kitchen installation situation made it not feasible to open the dishwasher. Because of that issue, the solution was to switch the locations of the fridge and stove. So we commenced trying to rearrange the power and water needs of both. This task turned out to be difficult because the cabinets are already installed and all the wires and hoses had to be weaved around drawers and cabinet corners.
- Christopher Thomson
