MI homeowners: Is your garage insulation doing its job?
If your garage shares a wall or ceiling with your living space, chances are it’s affecting the comfort of your home more than you think.
From freezing bedrooms over the garage to drafts sneaking in through uninsulated walls, garages are one of the most overlooked areas in home energy upgrades.
In this guide, we’ll cover:
If you live in Southeast Michigan and want to find out whether your garage insulation is doing its job, give us a call at (248) 291-7815, or send us a message:
Based in Farmington Hills, we’ve helped more than 3,000 homeowners with insulation and other energy-saving projects since 2009. Price match and satisfaction guaranteed.
Why garage insulation matters
A poorly insulated garage can make adjacent rooms the most uncomfortable in the house. Bedrooms above garages are often the hottest or coldest in the house - especially if the ceiling or shared walls are poorly insulated or not air sealed.
Insulation and air sealing work together to create a clear thermal boundary between your living space and the outside world, including the unconditioned air (and occasional fumes) in your garage.
Think of it like wearing a jacket on a cold day: no insulation is like going out without one. And insulation without air sealing? That’s like leaving your coat wide open - the warmth escapes, and the cold sneaks in.
Beyond comfort, properly insulating and sealing your garage helps:
- Reduce your energy bills by keeping conditioned air inside your home. According to ENERGY STAR, air sealing and insulation save an average of 15% on heating and cooling costs.
- Block unwanted drafts and fumes from entering shared walls or ceiling cavities.
- Improve indoor air quality and safety by limiting the risk of carbon monoxide and other pollutants seeping in from car exhaust or stored chemicals.
- Create a stronger buffer between your home and Michigan’s temperature swings - the high-highs of summer and low-lows of winter.
Whether you use your garage for storage, a workshop, or occasional hangouts, insulating and sealing it right helps protect the rest of your home and the people in it.
Key areas to insulate in your garage
Every garage is different, but here are the most common spots we target:
1. Garage ceiling insulation (especially if there’s a room above it)
This is priority number one. If you’ve got a bedroom or office over the garage, that room is likely suffering due to heat loss and gain through the ceiling below. We typically install high-R-value spray foam insulation between the floor joists, and if there's an attic above the garage, we insulate that too.
2. Wall between the garage and the house
This shared wall is crucial. If it’s not properly sealed and insulated, cold air from the garage can leak into the home. We also make sure any wiring or ductwork penetrations are air sealed.
3. Knee walls and attic spaces connected to the garage
If your garage has storage spaces tucked under rooflines or behind walls, these areas often get skipped during initial construction. Adding insulation here helps eliminate hidden drafts and heat loss.
What about garage doors and windows?
While they’re not the first place we focus, upgrading to insulated garage doors or sealing leaky windows can help round out the project - especially if you spend a lot of time in the garage. This often makes the most sense for homeowners who use the garage as a studio or workshop.
Got a project in mind?
When to consider HVAC in the garage
Air sealing and insulation should always come first. Without them, any updates or additions to your HVAC system will be inefficient—or basically useless. You’ll just be heating or cooling the great outdoors.
In most Michigan homes, garages already have ductwork connected to the main HVAC system. In those cases, improving insulation and air sealing is usually enough to make a noticeable difference in comfort and efficiency.
A ductless mini split might make sense if:
- You’ve already insulated and air sealed your garage
- You don’t have existing ducts running to the space
- You spend a lot of time in the garage - like if it doubles as a workshop, gym, or art studio
But even then, insulation is step one. Without it, you're throwing energy and money out the window—no matter how efficient the heating or cooling system is.
How to insulate a garage
Wondering how to insulate a garage the right way? It’s not just about adding more insulation - it's about using the right materials in the right places, with proper air sealing to back it up.
Here’s how we typically approach garage insulation in Southeast Michigan:
1. Start with an energy audit
Every home is different. A professional energy audit will help identify exactly where insulation is missing or underperforming - whether it's the garage ceiling, shared walls, or attic access points.
2. Air seal first
Before we add any insulation, we always seal gaps, cracks, and penetrations in the garage ceiling and walls. This keeps cold air (and garage fumes) from seeping into the living space and improves the performance of your insulation.
3. Choose the right insulation for the job
For garage ceilings with rooms above them, we usually recommend high-density spray foam for its air sealing and thermal benefits. In other areas, we may use blown cellulose, depending on your garage structure and goals.
We always recommend closed-cell spray foam over open-cell because it’s more resistant to moisture, mold, and mildew - all of which can be real concerns in Michigan’s climate.
4. Don’t forget ventilation
If your garage has attic access or roofline storage, we make sure insulation doesn’t block ventilation pathways. That helps prevent moisture buildup and extends the life of your building materials.
5. Consider comfort extras
If your garage doubles as a workspace or studio, we can also look at upgrading doors, sealing windows, and adding HVAC - but only after the insulation is dialed in.
Insulating a garage is a smart, high-impact upgrade, but the results depend on doing it right. If you’re thinking about tackling this project, we’d love to take a look and show you what your home needs.
Start with a home energy audit
A professional energy audit gives you clear answers and measurable results. You’ll see exactly where your home is losing energy and how insulation and air sealing will improve comfort and cut costs.
Since 2009, Ecotelligent Homes has helped thousands of Michigan homeowners make smart, cost-effective upgrades. Ready to find out what your garage needs? Give us a call at (248) 291-7815 or send us a message to schedule your audit.
Ecotelligent Homes
Since 2009, Ecotelligent Homes has completed more than 3,000 projects in Michigan. If you need help with new insulation, efficient HVAC, or abatement services, give us a call anytime: (248) 291-7815. Satisfaction guaranteed.
Got a project in mind?
Tell us about your project, and we'll send ballpark pricing in 2 minutes or less.