As the snow piles up and the wind howls across Michigan neighborhoods, insulation becomes a top priority for homeowners looking to keep warm and reduce heating costs. Whether your home was built in the 1970s or recently constructed, insulation directly impacts how comfortable—and energy-efficient—your winter will be.
In this winter insulation guide, we’ll explore spray foam vs. fiberglass insulation, explain the pros and cons of each, and help you choose the best insulation for Michigan homes. If you’re prepping for the cold, here’s what you need to know.
Quick Comparison: Spray Foam vs. Fiberglass
| Feature | Spray Foam | Fiberglass |
| R-Value per inch | ~6.0 (closed-cell) | ~2.9–3.8 |
| Air sealing ability | Excellent | Poor–Moderate |
| Moisture resistance | High (closed-cell) | Low |
| Lifespan | 30+ years | 15–20 years |
| Cost | Higher upfront | Lower upfront |
| Installation complexity | Professional only | Can be DIY or pro-installed |
Why Insulation Matters in Michigan
Michigan homes face all four seasons, but winter demands the most from your insulation. Your attic, crawlspace, and wall cavities need to combat:
- Sub-zero temperatures
- Ice dam formation
- Wind infiltration
- Moisture buildup
- Freeze-thaw cycles
Choosing the right insulation type isn’t just about comfort—it’s about long-term home protection and saving money on heating bills.
Spray Foam Insulation: Pros and Cons
Spray foam is a high-performance insulation material that expands to seal gaps, cracks, and cavities. It’s ideal for stopping air leaks and works well in tricky spaces.
Pros of Spray Foam:
- High R-value, especially with closed-cell foam
- Seals both air and moisture
- Long lifespan (30+ years)
- Reduces energy loss and cold drafts
- Helps prevent ice dams in attics
Cons of Spray Foam:
- Higher upfront installation cost
- Must be installed by a licensed professional
- Can trap moisture if incorrectly applied
- Not always necessary for interior walls
Fiberglass Insulation: Pros and Cons
Fiberglass remains one of the most widely used insulation materials, often found in batts, rolls, or blown-in form.
Pros of Fiberglass:
- Budget-friendly insulation option
- Readily available and easy to source
- DIY installation possible in some cases
- Fire-resistant and non-combustible
- Great for new construction or large attics
Cons of Fiberglass:
- Lower R-value per inch compared to foam
- Can sag or settle over time
- Less effective at sealing air leaks
- Prone to mold if exposed to moisture
- Doesn’t work well in oddly shaped cavities
Best Use Cases for Each Type in Michigan Homes
Spray Foam Is Ideal For:
- Rim joists and basement headers
- Crawlspaces or areas prone to moisture
- Attics where air sealing is a priority
- Older homes with irregular framing
- Preventing ice dams and cold drafts
Fiberglass Is Ideal For:
- New construction with clean framing
- Large attics with consistent rafter spacing
- Interior walls where air sealing isn’t critical
- Homeowners seeking affordable upgrades
Pro Tip: Many Michigan homeowners benefit from a hybrid system—spray foam in air-prone areas like rim joists, and fiberglass in wide-open attic spaces to balance cost and efficiency.
FAQ: Common Questions About Winter Insulation in Michigan
What’s the best insulation for Michigan homes?
Closed-cell spray foam often performs best in extreme conditions, thanks to its R-value and air-sealing ability. But for budget-friendly projects, fiberglass still works well when combined with proper air sealing.
How do I know if my insulation is failing?
Watch for:
- Uneven indoor temperatures
- Cold drafts near walls or outlets
- Ice dams forming on the roof
- High heating bills
- Discolored or compressed attic insulation
Can I add spray foam over fiberglass?
It depends. Spray foam can be applied over some types of existing insulation, but the fiberglass must be dry, mold-free, and structurally sound. In some cases, removing the old insulation first is better.
Is attic insulation really that important?
Yes. Up to 25% of a home’s heat loss happens through the roof. Ensuring your attic is sealed and properly insulated has one of the highest energy-efficiency paybacks for Michigan homes.
Upgrade Before the Cold Hits—We’re Here to Help
At Big Rapids Roofing, we don’t just protect homes from above. Our team helps Michigan homeowners improve their homes’ energy performance with winter-ready insulation solutions, including attic upgrades, ventilation improvements, and ice dam prevention.Not sure what you need? Get a free estimate now and let our experts evaluate your home and recommend the best insulation system for your climate, budget, and long-term comfort.
