Fiberglass insulation for exterior applications is one of the most widely used and cost-effective methods for improving a building’s energy efficiency. It comes in batts or blown-in form, and is installed in exterior walls, attics, and roof systems. Fiberglass works by trapping air in its tiny glass fibers, slowing the transfer of heat and helping maintain consistent indoor temperatures.

Why homeowners choose fiberglass for exterior use:

Affordable and easy to install in new or existing homes

Helps keep indoor spaces warm in winter and cool in summer

Fire-resistant by nature, adding a layer of safety

Can be paired with air-sealing measures for better efficiency

Reduces heating and cooling bills year-round

Best for: Exterior walls, attics, roof systems, and additions

Fiberglass is also an excellent option for interior applications. When installed in interior walls, floors, or ceilings, it helps regulate temperatures and provides a basic level of sound control. While it’s not as dense as mineral wool, it still offers comfort, affordability, and flexibility.

Why it works indoors:

Reduces sound transfer between rooms

Cost-effective option for interior walls and ceilings

Lightweight and versatile for most construction types

Fire-resistant and safe when properly installed

Easy to upgrade in remodeling projects

Best for: Interior walls, basements, and ceiling cavities

Roxul, also known as mineral wool, is made from natural stone and recycled materials. It’s denser than fiberglass, which makes it an exceptional choice for exterior walls and areas where moisture resistance and durability matter most. Mineral wool is naturally water-resistant, meaning it won’t absorb or hold moisture, making it a safer option in climates with heavy rain or snow.

Why it excels for exterior use:

Excellent thermal resistance in extreme weather

Water-resistant and mold-resistant

Naturally fire-resistant — withstands temperatures over 2,000°F

Provides superior noise reduction compared to fiberglass

Eco-friendly and long-lasting performance

Best for: Exterior walls, attics, and high-moisture or fire-prone areas

For interior applications, Roxul delivers unmatched soundproofing and fire safety. Its dense composition makes it highly effective at blocking sound transfer between rooms, making it a popular choice for bedrooms, offices, and multi-family housing. It also offers peace of mind with its non-combustible properties.

Why it’s great indoors:

Superior soundproofing for quieter, more private spaces

Fireproof and safe for use around furnaces, fireplaces, or utility rooms

Dense material adds comfort and energy efficiency

Eco-friendly option made from natural and recycled stone

Doesn’t sag or settle over time

Best for: Interior walls, ceilings, home offices, bedrooms, and multi-unit housing