Tag: U-factor

Posted on

The Effects of Poorly Installed (or Missing) Insulation

I was taught many years ago by an older fiberglass insulation contractor the importance of a quality insulation job.  His biggest piece of advice, FLUFF, DON’T STUFF!  Poorly installed insulation can have a big impact on the overall performance of a home.  In this blog, I’m going to show you mathematically how a small insulation deficiency can have a big effect in how a home performs.

This thermal image is a good example.  This was a brand-new home where I was performing a code required blower door test.  I ran around the home with my thermal imaging camera before starting the test and thought I might be able to use this image to show thermal bridging, which it does a good job at, but if you study the pic a little closer, we see several areas where the fiberglass insulation was poorly installed.  Compressing (not fluffing) the product creates areas of cooler temperatures in the insulation batts.  The dark area (at the ceiling on the right side of the photo) shows an area of missing insulation.  What effect does this poorly installed insulation have on the overall (effective) R-value?  We can show the results mathematically.

Continue reading “The Effects of Poorly Installed (or Missing) Insulation”

Posted on

What’s the Difference Between R-Value and U-Factor?

This post first appeared on the Andersen Windows and Door Website.

We were taught in junior high that hot air rises, the key to that phrase is air.  Heat itself moves from someplace warm to someplace cool.  A good example of this happens often in cold climates.  When standing in front of an old window on a cold night, you feel a chill.  This chill is the result of heat leaving your body and moving towards the colder surface of the window glass, heat moving from hot to cold.  To slow this movement of heat, we use insulation, by putting on another layer of clothes, we reduce or resist the movement of heat, we have added R-value.

Continue reading “What’s the Difference Between R-Value and U-Factor?”

Posted on

Construction Design-Windows-Climate Matters

This post originally appeared on the Andersen Windows website.

Where do you live?  Is it cold or hot, wet or dry, or something in between?  I live in an area that is considered cold and moist, Northern Minnesota.  My climate is much different than Tucson, Arizona or Kansas City, Missouri.  Because of the climate differences, some of my choices in building materials will be different than if I were located in one of those other areas.

Figure N1101.7 (R301.1) Climate Zones-2021 International Residential Code (IRC)

This climate zone map is published by the American Society of Heating and Air-Conditioning Engineers (ASHRAE) and is included in the International Residential Code, Chapter 11, Energy Efficiency.  ASHRAE’s purpose is to create standards of how an engineer or HVAC professional calculates and designs heating, cooling, and ventilations systems to match the insulation, air sealing, and moisture profile of a building.  When designing these often-complicated systems, where the structure is located becomes key, this is the reason the map was created. Continue reading “Construction Design-Windows-Climate Matters”

Posted on

Window R-Values

This blog post originally appeared on the Alpen Window’s website.  https://thinkalpen.com/.  I had the opportunity to tour the Alpen plant recently and was very impressed with the windows they make.  There will be more content featuring Alpen Windows in the near future.

Heat is a funny thing; it wants to move from someplace warm to someplace cold, (the opposite of being a snowbird) and it’ll continue to move until it has reached equilibrium.  In the heat of the summer or cold of winter, that means if we can’t slow the movement of heat, the temperature of the outside will be the same as the temperature of the inside.  This might be 110°F or -25°F, neither is appealing.  Of course, we heat and cool our buildings to maintain comfort, but these systems work best when we’re able to slow this constant march of heat leaving or entering the building, we do this with insulation.

Continue reading “Window R-Values”