When building your custom home in a cold climate like Michigan it is very important to understand the many options you have to best insulate your home, as it is not a “one size fits all”. Here are some of the options you may be familiar with:
Mineral wool batts
Blown in fiberglass
Blown in cellulose
Wet sprayed cellulose
Polystyrene foam board
Polyurethane spray foam (open cell and closed cell)
It is important to have a conversation with your custom home builder early about your options as it not only affects your long term costs (think energy loss and utility bills) but it also has a great impact on your upfront cost of the home. Your builder should be your trusted source for gaining an education on materials that go into your home and the effects they have on it as well as the budget.
For above grade walls there are a couple options we use most commonly.
Wet spray cellulose
Wet spray cellulose is a great option as it offers a good R-Value (capacity of an insulating material to resist heat flow), is more cost effective and environmentally friendly when compared to open and closed cell foam. From a performance standpoint, because it is installed wet, it fills cavities and doesn’t have the tendency to settle over time like blown fiberglass. When using wet spray cellulose it is extremely important that your builder allow enough time for the insulation to dry. The time required to dry really depends on the time of year and where in the construction cycle your home currently is. A furnace, air conditioner, dehumidifier or fans can help speed up the drying cycle. It is advised to wait on drywall installation until the moisture is out of the insulation. While wet spray cellulose does seal up air leaks better than batt insulation and dry blow products it is advised that your builder include a seal package from the insulation installer which consists of caulking potential air gaps to help reduce air leaks.
Open-cell polyurethane spray foam
Open-cell polyurethane spray foam is another nice option as it offers many of the same advantages as wet spray cellulose but with better air seal qualities. Even though it is a bit more costly, the main advantage of open cell foam as compared to wet spray cellulose is that it saves the dry time which can allow you to speed up the construction process. Because the rim joist (area where above grade wall meets the foundation) is considered one of the leakiest areas of the home and is difficult to insulate, spray foam is a good solution as it fills up the cavity and seals off any leaks.
According to building science consultant Andrew Lesperance of GreenEdge of Michigan, the attic is the most important area of the home to insulate in cold climates like Michigan. Coupled with the correct ventilation, properly insulated attics are key to avoiding ice damming which can cause many large issues. Blown cellulose is cost effective, denser than blown fiberglass and settles nicely into joist cavities, making it a great attic solution.
Whitmore Custom Homes is focused on ensuring every step of your home building process is a positive one. Whether it’s navigating the ever changing energy code or talking about the advances in insulation technology we would love to work with you on your dream home.