What does it mean to build a super insulated home? I often get asked what my recommendation for insulation is. Both the type of insulation to use, and how much. But let me ask you a different question. What are you really looking for in your home? Comfort? Savings? Seriously I've never asked a group full of people if they'd like to spend less on utilities and had them say no! Maybe you're ready for retirement and you want to be able to shut it down for the winter and go south. Wouldn't it be great not to worry about frozen pipes or high heating costs when you're not there? But maybe you're the person who has to have beautiful granite countertops? Let me ask you, do you want to build a brand new dream home with all the interior bells and whistles and then sit around with three sweatshirts because it’s drafty or cold? If you answered, "Yes. I don't care how much it costs i'll just turn the heat up" then you should probably stop reading now. For us, we'd rather do the "hard to change" things right the first time, and come back and add the bells and whistles when we aren't using as much to operate our homes.There are so many components that go into a super insulated home. Simple things that have no cost like orienting your house the right direction. Or taking the time to think about where windows are positioned and how they are positioned. Our favorite thing to do isn't to spend thousands of dollars on windows, but to pick the right ones in the right locations, and minimize them everywhere else. These two things make a huge impact on the quality of the space within the home. If you've met me, you know I always say "Every house has an ugly side, let's make it the North side". Building a super insulated home may not be about the flashy and attractive things that people see when they walk into your house. Instead, it's about comfort. Super insulated homes are designed for the people inside. There are three things that affect our comfort levels: Temperature, Air Movement, and Humidity. Super insulated homes reduce air infiltration, heat loss, and control the interior moisture. They are specifically designed more maximum comfort. Reducing the unhappiness of the occupant significantly reduces the use of energy in the home. So let us tell you a little bit more about the “less beautiful” parts of your home that actually make your space so much more attractive.Tip number 1: Improving the insulation in your home is the hardest thing to do after it's built, and let's be honest, you'll never do it. So don't skimp on this part. Don't let this be the first thing you ask your builder to compromise on. If your budget is tight, let us tell you what things to do later that are super easy to replace or add. So let me give you my thoughts on insulation:
- All of my builders know not to utter the word “fiberglass insulation” in my presence unless we are talking about how to insulate a bedroom or bathroom for sound transmission. Fiberglass is cheap and cheerful and always installed by the guy who gets paid the least on the crew. It’s rarely installed correctly and it’s even more rarely installed in a vacuum (ie completely air tight cavity). Fiberglass insulation works by trapping air pockets in between all the fibers, however, building is rarely 100% air tight, so when air moves though the fiberglass fibers it eliminates the pockets of air and makes the fiberglass insulation more of a filter and less of an insulator. We’ve all seen dirty fiberglass, and that’s why.
- Cellulose, we love cellulose and use it almost exclusively in our projects. A properly dense packed wall will move and shift with the building as it drys out after construction. Dense packed cellulose insulation retards air infiltration making the house tighter and the insulation more effective. And it’s fire resistant. Yes, it can hold 130% of it’s weight in water if it gets wet. Although it’s not possible to make a completely air-tight structure, we are in the practice of making water tight structures, so we worry very little about moisture getting into our wall cavities. Does it mean it never happens, no, but we’ve had so few problems with it we would not hesitate to recommend it.
- Spray foam is probably the 3rd most popular insulation choice. Like all of the insulations it has good and bad properties. It air seals very well and can make extremely tight buildings. But it’s also a solid insulation, so when the building settles and dries out over the first couple of years, it can crack and pull away from the structure. It’s also pretty nasty, most foams are made of plastic and the agent that is used to make it liquid to install, cure, and dry is often toxic requiring specific equipment to install it and mandatory building evacuation for 24 hours or more. It’s not flame resistant and has to be covered by a 15 minute thermal barrier or sheetrock which can add expense and only gives you time to get out of the building. Once it starts burning it gives off toxic fumes that are extremely dangerous.
Here's the nitty gritty. When someone asks me for my recommendation on insulation I recommend the following: R-40 in the walls and R-60 in the ceiling. In cold climate building we also add 2”-6” of rigid foam below the slab. To get a little more complicated, I also try to minimize something we call thermal bridging. Essentially, thermal bridging is a path from the interior to the exterior of the home with little to no insulation. If you think of a standard wall construction, you have studs with insulation in between the studs. The thermal bridge happens at the studs. Wood has an R-value of 1 per inch. Everywhere you have a stud in a typical wall it has an R-value of 5.5 in a 2x6 construction. In between each stud you have insulation with an R-value of 19. So the stud at 5.5 is the poorest performing section of your wall and a direct path for cold to transfer from outside to inside.And lastly, but most importantly, super insulated homes aim to be as air tight as possible. Every seam, crack, gap, or location where two materials meet is sealed with foam or caulking. It’s a common misconception that buildings need to breath. People need to breath, buildings don’t. Does that mean you don’t need fresh air? Absolutely not!!! What it means is that we control how much and where that air comes from. Instead of travelling through your dusty insulation and your dirty basement, we introduce that fresh air directly from outside. In addition to being able to control where the air comes from, it's equally as important to control how much air comes in. Most people probably remember from high school science that hot air rises. Well when that air rises and exits through your attic you have to heat the air that comes in to replace it. So the draftier your house is, the more it costs to keep it warm. And if you remember from a couple paragraphs ago, our comfort levels are directly affected by air movement.Yes, I'm asking you to spend more during construction to put in better insulation and air seal everything you possibly can. But if I could prove it would pay for itself in a very short amount of time, would you be interested in knowing how long?We hope you’ll visit again to learn more about insulation, windows, geo thermal and air source heat pumps, zero energy, and lots of other cool building related topics over the next couple of months. Reach out to us and let us know your questions, we are always happy to answer any questions you might have, and several other people reading this blog may have the same exact question, so you’re doing them a favor by reaching out!Until next time, have a warm and comfortable life!