The first Construction Tech Tuesday kicked off ten days ago with a look into how you go about installing an enormous skylight in a Passive House project. To fully dive into the presentation and the discussion that followed, view the video below and take to heart the insights offered by cohosts Shaun St Armour (475 High Performance Building Supply), Kevin Brennan (Brennan Brennan), and Mark Willie (Tstud) as well as by guests Michael Ingui (Baxt Ingui), Maggie Hummel (Baxt Ingui), John Mitchell (bldgyp), and Ben Leer (Vital Sustainability).
What follows is just a quick listicle of some of the key points that came up during the event.
1. Fluid vs. Tape?
While there’s plenty of debate and varying viewpoints about the performance fluid versus tape in diverse circumstances, this team’s perspective was that tape is best used for sealing around windows while fluid is best everywhere else. The performance difference appears to be miniscule and caulking around windows is time consuming. The same is true for skylights.
2. Wipe it Down
Tape needs to be applied on smooth surfaces that are clear of any dust or moisture. If these areas are not clean, the adhesives are not going to be able to do their job. The problem is that no construction site in the history of building has ever been free of dust. It’s a simple fact of life. This is why you should always have some wet wipes on hand.
Before you make a stink about the problem of fatbergs or the cost of buying wet wipes or the fact that they aren’t biodegradable, you should read this article here about making your own. (Note: you can probably skip on the tea tree and lavender essential oils.)
3. Look for Ghosts
For those who seen the show Ghost Adventures (don’t judge), you are familiar with the FLIR camera. It’s the instrument that measures infrared radiation and it clearly reveals cold spots. While the Ghost Adventures crew may think that some of these cold spots represent paranormal manifestations, a good building scientist or contractor knows that these anomalies tend to be nothing more than the lingering specter of a bad insulation job. That being said, these cameras can be used on cold days to measure even tiny heat differentials in problematic areas, giving you the chance to spot check your work and apply more sealant as necessary.
4. The Red Door of Truth
The blower door test is the kind of thing that keeps designers and contractors awake at night, but it can have a life outside of the one thing standing between you and your Passive House plaque. If used a few times during the construction process, the blower door can reveal small holes and minor mistakes that can usually be corrected pretty easily. Kevin Brennan recommended running one test after the initial air barrier is installed, a second after the windows are installed, a third after the insultation has gone in, and a fourth before the door of the home gets installed.
5. You Are Going to Screw Up
There are really two points hidden in this message. The first is that no matter who you are or how long you’ve been working on Passive House homes, there will be leaks, especially in the case of a retrofit. That said, you should, first, have some humility. Your ego needs to go out the door if you want to have a successful project. Second, include some time to check for leaks in your construction schedule. In the worst-case scenario, you use all these days and end on time. In the best-case scenario, you finish early.