Month: February 2022

The weather has been just right for window installs and the team wasted no time getting the openings cut and air sealed. The cutting was done with a simple handheld router and Prosoco FastFlash was used to do the air sealing over the rough framing. This was then followed up with backer rod then sealed to the frame with Prosoco AirDam. We also finished the air sealing between the wall and foundation with Prosoco Joint and Seam Filler. Let’s start with that detail to keep things in chronological order.

Stephanie was in charge of cutting the under-slab vapor barrier flush with the wall and gunning out the sealant (pink), then David followed up with a spatula to create a continuous barrier ~4 inches wide spanning block and sheathing.

What a huge improvement the few holes and windows can make on a large “green canvas.” This was an exciting time for us as this was a beautiful step on our home building journey.

Here are some shots of the sealed interior prior to any finish work.

I also need to give credit for the rest of the air sealing detail on the exterior of the house as there were MANY joints and seems that needed to be sealed. This process is critical, but since it’s on a smaller scale, it doesn’t make for great pictures. I did get a shot of the team on the lift though.

One more bonus photo. We just got excited to see the beautiful light streaming in through our upstairs windows, yeah!!!

For those who haven’t heard the short story about our “wings”, when we were doing our home design, we realized very quickly that we needed to be very explicit when we were referring to locations and building and Stephanie came up with the wonderful idea to refer to the buildings using a simple A, B, C mnemonic.

A = Activities
B = Bedrooms
C = Cars

This then turned into the A-wing, B-wing, and C-wing. This has helped us through all conversations with those involved in the building project. All that so say that this post is meant to give updates on the C-wing as that has been the focus for the past few weeks.

Please note that the building style and materials are the same, but we are not trying to achieve any Passive House certifications on this wing. Let’s get into some pictures.

We can’t believe all buildings and roofs are on, we are so pumped. If you look at the pictures and the dates, you might notice major changes in February, but not so much in January. You may have guessed that the snow hit us pretty hard in January, but has let up enough now for work to accelerate. We hope to have the rest of the building joints sealed up with some warm weather next week, then the windows (yeah!).

Here is the latest drone flight from 2022-02-11: https://youtu.be/5bze6J5oiMU

It’s that time to get a little data behind the house again. You may have heard the old phrase, “a house needs to breathe”, but without giving that phrase some good thought, it’s easy to miss in important factor. To control air, you must first contain air. I took that phrase from Joe Lstiburek. It’s fairly common sense to understand that air contains moisture, temperature, and contaminates (pollution, pollen, etc). Having these things drifting uncontrollably in and out of your home through a leaky house, is the traditional meaning of a house that breathes, not what we are trying to accomplish, controlling this air requires some work.

We have worked hard to design an air control layer for our home. This control layer consists of certain materials, design decisions, and install methods. We then test the quality of our work with an air leakage test to make sure we achieved the level of designed air control. For us, that would be < 0.6 ACH @ 50 pa. ACH is the Air Exchanges per Hour and the 50 pascals is a unit of pressure. This test is performed by doing a blower door test. Here is a video of a blower door test being performed with some great explanation of Passive House air tightness, https://youtu.be/B8UFGnHmFJ4.

Alright, now that we have a tight house with an optimal air control layer, which reduces our energy loss, improves the life of the building, and allows for controllable air quality. We will be using a fresh air system called an Energy Recovery Ventilator (ERV) that will be centrally controlling the fresh air coming in and stale air going out. This allows us to fully control the flow of fresh air into the house and filter that air on its way in. This system will use small 2.5” flex ducting to bring fresh air to all rooms. Fresh air should be controlled in many normal homes, but that is a topic for another day. Details on the model of ERV and ducting were in my previous post.

We can’t wait to share this house with friends and family (which is why we are building it). We’ll continue to follow up with progress after we get a bit more done this week with some sun coming. We also plan to go over a solar / electric design in more depth in the near future.