Construction Design-Insects and Rodents

When I purchased my old home, the 1952 Cape in late 2018, the basement area looked good.  Someone took the time to paint all the concrete walls and floor and cleaned everything up to look nice.  Shortly after we moved in, the cat caught a mouse and then the following summer, the basement became a bug gathering place.  Ants, spiders and other bugs apparently wintered in another area and returned to my house in the spring.

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Construction Design-Using Fibrous Sub-Slab Insulation with In-Floor Heat

I’ve written about sub-slab insulation and heated floors several times over the past couple years, this post is about something I’ve been thinking about for a while now, using a fibrous insulation, like Rockwool’s ComfortBoard 80 or 110 under a concrete slab with hot water heat.  The questions I had about this strategy are one, will there be an issue with compression of the insulation when concrete is poured over the product?  And two, will a staple be able to hold the hot water tubing in place?

Rockwool ComfortBoard being installed below a concrete slab.  Photo by Travis Brungardt

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Building Science-Wintertime Interior Humidity

As I write this post at the end of November, our outdoor temperature is 28°F with an outdoor humidity of 75%.  Inside my home, the temperature is 70°F with a humidity level of 21%.  Slightly uncomfortable humidity levels for my family.  During last year’s polar vortex, when the temperatures reached nearly -40°F, my indoor humidity dropped to 9%, much too dry.  Knowing what I know about building science, I will not operate a humidifier.  This post will explain why. Continue reading “Building Science-Wintertime Interior Humidity”

Shorts-Fine Homebuilding Magazine Content

Several of the posts on my blog were first published on the website Green Building Advisor.  I’ve enjoyed writing for them, but my hope has been to get an article in their sister publication, Fine Homebuilding Magazine.  In issue #304, December 2021/January 2022, that finally happened.  Funny thing is, I didn’t get just one article published, I have two plus a tool review, oh, and I’m on the cover.

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Building Science-Three Way Buildings Leak Air

I have talked many times about blower door testing, air sealing and air leaks in this blog, on the Green Building Advisor’s website, and more recently, in the pages of Fine Homebuilding Magazine.  Most of what I’ve written deals with testing a home or techniques used in air sealing a home.  This time I’m going to discuss the mechanisms that cause air to leak, there are only three of them, but first a little science. Continue reading “Building Science-Three Way Buildings Leak Air”

Construction Design-Closed Cell Spray Foam Below a Slab

This post originally appeared on GreenBuildingAdvisor – Green Building Advisor is the one-stop source for builders, remodelers, architects & homeowners looking for expert advice on green products, strategies & proven construction details.

I was introduced to using closed cell spray foam (CCSF) below a slab a few years ago by New England contractor Wade Paquin of WKP Construction. He was insulating the below grade slabs of his new homes by spraying a couple inches over a bed of stone, then pouring the concrete. I have now had the opportunity to try this insulation method over a couple projects, Continue reading “Construction Design-Closed Cell Spray Foam Below a Slab”

Building Science-A Benefit of Exterior Insulation

I’m a big fan of exterior insulation.  It’s rarely used in my area, mostly because the State of Minnesota has eliminated that code requirement.  It has to to with our wide use of polyethylene sheeting as a vapor retarder on the warm in winter side of a wall assembly and then adding a low permeance plastic insulation product as exterior insulation.  These plastic foams would be the choice for most contractors, lower cost and easy to source.  Very slow vapor movement in either direction when a wall assembly becomes wet.  This posting isn’t going to get into the foam insulations, but more into what exterior insulation can do for a home. Continue reading “Building Science-A Benefit of Exterior Insulation”