Airsealing a 1970s Townhouse Attic | Building Science Project

Join us on this building science project as we tackle the challenge of air sealing a 1970s townhouse attic. In this video, we'll show you how to increase the efficiency and comfort of your home by properly sealing your attic space. With older homes, it's especially important to identify and fix air leaks to improve indoor air quality, reduce energy costs, and enable you to electrify your home. If you have a second floor, this also helps with "hot second floor syndrome" in the summer.
This video is the first of many that showcases the transformation of a leaky, poorly insulated 1970s townhouse into a "pretty good" townhouse (not quite passive house or net zero). The following videos will go over beefing up the insulation in the attic and attic ductwork, and airsealing & insulating a garage door, with many others to come - so make sure to subscribe!
With rising temperatures and high humidity levels in the Southeast, it's important to keep your floor properly insulated and airtight to reduce hot or cold air leakage and infiltration. Our step-by-step guide will take you through the process of identifying air leaks and sealing them with the right materials in order to increase home performance. By the end of this video, you'll have the knowledge and tools to complete your own attic air sealing project and enjoy a more energy-efficient, comfortable home. Don't forget to like, comment, and subscribe for more home improvement tips!

[@jeffwilliams9086]

Good job, helpful video, thanks!

[@koomo801]

Nice work, and editing! Seems like mastic paste would be a good (better?) solution for your metal to metal or ductwork sealing, but you were able to do it with what you had. I need to do this on two homes, and am dreading it.

[@byronsinclair3956]

Why is flashing laid down over the rockwool? Is it to keep the rockwool from being pushed down further into the cavity? Will there be any additional videos regarding air sealing, attic insulation, or follow ups?

[@andrewmist5544]

What's the difference in the bill?

[@XsoloXela1989]

I get you're creating a barrier with the flue, but shouldn't you use high temp caulk instead of foam with the flashing? I have a range hood exhaust vent I was planning on flashing with high temp caulk

[@markr857]

Aluminum is not code compliant in this application. Code requires steel. Also, foam fire block foam is not code compliant in contact with flues. Code requires sealant rated for continuous exposure to higher temps. High temp silicone for gas flues, and ASTM 136 compliant sealant for wood or pellet fired appliances. My insulation company uses 3M FB 136 or DAP High Heat Mortar for all flues.

[@pearlperlitavenegas2023]

Get a gun & larger cans of foam it's cheaper than the smalk cans

[@mattwilson7443]

Isn’t the gun itself $60? He’s only using two cans in the video

[@chrissund4889]

Your foam is coming out crappy because it needs to be upsidedown.

[@redsresearch]

not sure if this is correct