Eric George is a Louisville KY specialist with over 15 years of experience in new construction and building restoration fields, particularly insulation and weatherization. He is also the president of Building Performance Group – an organization that helps local homeowners and builders adhere to the highest efficiency standards. In this podcast, custom luxury home builder Jason Black (www.artisansignaturehomes.com) asks Eric about insulation and basements.
According to Eric, there are three main types of insulation found in new homes today:
- Traditional fiberglass rolled insulation (fiberglass batts):
- Cellulose insulation – made from recycled newspaper and chemically treated with boric acid so it’s fire retardant and mold/mildew-resistant
- Spray foam – which acts as an air barrier and insulation in one
Spray foam generally produces a more air-tight seal, but quality of materials and application matter most. “We want to make sure that the insulation material completely fills the wall cavities,” Eric explains. “It’s getting behind and around electrical wires and pipes and stuff that are in the walls. When you’re using a product like fiberglass-rolled insulation, that insulation has to be split in half and tucked behind wires, and it’s kind of more of a manual process to do it right.”
Eric finds that insulation “hardly ever gets installed the way the manufacturer said it should be installed.” They grade insulation installs on a scale from 1 to 3 (with 1 being perfect and 3 being terrible.) “Most fiberglass batt installs are going to be a three,” says Eric. On the other hand, “If you’re using a blown-in cellulose or a blown-in fiberglass in your walls, it’s going to completely fill that wall cavity. It’s going to get all behind the wires and the pipes. That’s going to effectively be a grade one as long as it’s completely filled.”
Artisan Signature Homes hasn’t used traditional fiberglass batts in a while, but it’s still the most common method for insulating homes in the area. “The Pink Panther from Owens Corning’s got it drilled in our head that he’s the way to go and so most builders use fiberglass insulation, whether it’s good or not,” Eric laughs, adding: “It’s fast and it’s cheap.”
In the basement, concrete walls need four feet of insulation, as per code requirements. Most people don’t know this, but eight inches of concrete has the same heat transfer resistance as a single-pane glass window. “Concrete absorbs heat really well and it releases heat really well. It also absorbs moisture vapor really well and releases that into the house,” Eric says.
Homeowners have two options for insulating a basement:
- Frame it up and put insulation between the studs
- Put a foam board or spray foam directly on the concrete
“My opinion and our experience has showed that it actually is a lot more effective to put the board or the spray foam right against the concrete so that you don’t have kind of a gap between the wall and the insulation where air can circulate.” This method will produce a noticeable difference in the comfort of the home, Eric says.
When inspecting local homes, Eric says they just about always find something – especially with custom homes because they’re larger and more complex – so they like to get involved early on in the design phase of building, whenever possible. Eric explains: “We find disconnected duct work in houses that are about to get drywalled. We find sections of ceilings and walls and rim joists that have been missed insulation or improperly insulated. There’s all kinds of weird stuff that we find in new homes. Builders are busy. They have a lot of things going and they’re not necessarily paying attention to the detail that we are.”
Tune-in to the complete podcast to learn more about:
- What Eric George calls “basement diapers” and what he doesn’t like about this method of basement insulation
- A professional opinion on zoned heating and cooling systems in the home compared to proper ductwork sizing
- Why it’s a bad idea to throw a zone damper system on a basic furnace
- How to ensure that your custom home has the most efficient setup