9 Best Attic Insulation Materials: Pros, Cons, and RPM’s Top Pick

When it comes to keeping your home comfortable and energy-efficient through harsh Canadian seasons, the right attic insulation makes all the difference. Homeowners in Ottawa, Cambridge, London, Dartmouth, Montreal, and Calgary often face unique climate challenges, making the choice of attic insulation even more crucial for lasting comfort and savings. At RPM Home Services, we offer expert attic insulation solutions, combining decades of experience with trusted materials to meet every local need.

Understanding Attic Insulation Materials

Attic insulation serves as your first line of defense against heat loss in winter and excess heat gain in summer. With so many options available, choosing the ideal insulation material can seem overwhelming. Below, we break down the nine best attic insulation materials, covering their pros and cons, and finish with RPM Home Services’ professional recommendation for homeowners across Canada.

1. Fibreglass Batt Insulation

Benefits:

- Widely available and affordable

- Simple installation process

- Good fire resistance

Drawbacks:

- Gaps can occur if not installed properly

- Susceptible to moisture and mold

2. Blown-in Fibreglass Insulation

Benefits:

- Fills attic gaps and irregular spaces thoroughly

- Excellent coverage and R-value (thermal resistance)

- Quick, non-intrusive installation

Drawbacks:

- Professional equipment required for optimal results

- Can settle over time if disturbed

3. Cellulose Insulation

Benefits:

- Made from recycled paper, environmentally friendly

- Strong air-sealing qualities

- Resistant to insects and pests

Drawbacks:

- Absorbs moisture easily, prone to mold growth

- May settle more than some alternatives

4. Spray Foam Insulation

Benefits:

- Creates an effective air barrier and high R-value

- Seals hard-to-reach cracks and crevices

- Adds structural strength

Drawbacks:

- Higher upfront cost

- Professional installation necessary

5. Rockwool (Mineral Wool) Insulation

Benefits:

- Natural fire resistance

- Excellent soundproofing

- Resists water and mold

Drawbacks:

- More expensive than fibreglass or cellulose

- Can be more challenging to install in tight spaces

6. Cotton (Denim) Insulation

Benefits:

- Made from recycled materials, non-toxic

- Easy to handle and install

- Good sound absorption

Drawbacks:

- Higher cost compared to traditional options

- Limited availability

7. Reflective Radiant Barrier

Benefits:

- Blocks heat transfer in hot climates

- Lightweight and easy to install with other insulation types

Drawbacks:

- Less effective in cold climates like Ottawa or Calgary

- Works best as a supplement, not primary insulation

8. Polystyrene (Foam Board) Insulation

Benefits:

- High insulating value per inch

- Moisture-resistant, ideal for damp attics

- Lightweight and easy to cut to size

Drawbacks:

- Gaps can occur if boards aren’t carefully fitted

- Combustibility concerns; requires careful installation

9. Vermiculite Insulation

Benefits:

- Resistant to fire and pests

- Good flowability for filling odd spaces

Drawbacks:

- May contain asbestos in older homes

- Not commonly used in new installations

How to Choose the Best Attic Insulation for Your Canadian Home

Your climate, attic structure, and specific energy goals all play roles in selecting the right insulation. Homeowners in snowy Ottawa or Calgary, for example, should focus on materials with high R-values and resistance to moisture. In Montreal and Cambridge, insulation that resists mold and mildew is paramount, especially in older houses with existing humidity challenges.

RPM Home Services’ Top Pick: Blown-In Insulation

After years of serving homeowners across Ottawa, Cambridge, London, Dartmouth, Montreal, and Calgary, RPM Home Services recommends Blown-In Insulation for most attic projects. Here’s why:

- Superior coverage for attics of all shapes and sizes

- Effective at sealing gaps and seams, reducing drafts

- Fast, professional installation minimizes home disruption

- Environmentally responsible options available, such as cellulose or fiberglass

Our team uses high-quality materials, advanced equipment, and proven techniques to ensure your attic insulation stands the test of time, saving you money on energy bills and improving year-round comfort.

Ready to Upgrade Your Attic Insulation?

Investing in quality attic insulation is one of the smartest ways to protect your home from energy loss, moisture problems, and sudden weather changes—especially in Canada’s challenging climate. Whether you live in Ottawa, Cambridge, London, Dartmouth, Montreal, or Calgary, the expert team at RPM Home Services is here to help.

Contact us today to schedule your professional attic assessment or get a free quote. Experience the RPM difference: unmatched expertise, quality materials, and a commitment to protecting your home and family.

Visit rpmhomeservices.ca or call your local RPM Home Services office now—let’s keep your home comfortable, safe, and energy-efficient all year long!