TimberFill
Cavity Insulation in Stud Walls and Between Rafters & Joists
TimberFill is a debris-free dense pack or loose fill wood fiber insulation proven to regulate temperatures and humidity in even the toughest climates.
| PROPERTY | VALUE |
|---|---|
| R-Value of Loose Fill at 75o F Mean Temperature | R-13 — R-60 per inch of settled thickness |
| R-Value of Dense-Pack at 3lbs Per Square Foot | R-13 — R-35 per inch of installed thickness |
| Thickness of Loose Fill | Up to 20.7 inches settled thickness |
| Thickness of Dense-Pack | Up to 9.26 inches installed thickness |
| Fire Resistance | ASTM E84 Class A <25 Flame and <450 Smoke spread |
Fire-Resistant
ASTM E84 ratings for flame and smoke spread performance through the use of borate.
High Thermal Performance
All-season thermal storage and draft reduction meets Passive House, LEED, and energy stretch code targets.
Acoustic Comfort
Excellent sound absorption supports privacy and comfort in multifamily and commercial interiors.
Carbon-Storing
Sequesters atmospheric carbon and is manufactured using environmentally-friendly practices.
Vapor-Open
Allows assemblies to dry out naturally, reducing risk of mold and other moisture-related issues.
Improved Air Quality
Itch-free, no added formaldehyde, VOCs, or harmful additives—Red List Free.
Applications
TimberFill insulation is suitable for use in both new construction and renovation projects.
Attic Blanket
As a loose fill attic insulation, TimberFill provides seamless coverage and exceptional thermal performance—helping regulate attic temperatures year-round while allowing moisture to escape naturally.
Floor, Ceiling, and Cavity Wall Insulation
Dense-packed into cavities, TimberFill insulation creates a high-performing, airtight thermal layer that controls temperature and humidity while reducing sound transmission across walls, floors, and ceilings.
Downloads
Installation
TimberFill insulation is designed for ease of use on site.
Download our full Installation Guide, or watch our installation how-to videos for step-by-step details and best practices.
Tools & Accessories
For the best results when cutting and fitting TimberBatt, the following tools are recommended for clean, efficient installation.
Bahco Insulation Saw
Durable and ergonomic with a stainless steel blade—great for straight and detail cuts.
Available Here
Custom TimberBatt Knife
Excellent for thicker batts or fast repetitive cuts. Serrated edge grips and slices easily through dense fiber.
Available Here
Linzen TimberBatt Knife
For volume cuts or production-speed installs, especially on larger jobs.
Available HereUse a timber offcut or cutting table underneath for safer, cleaner cuts and less mess on site.
TimberFill FAQs
What code compliance does TimberFill meet?
TimberFill meets IRC and IBC insulation requirements and ASTM fire and vapor standards. For third-party testing documentation, see downloads.
Can I use TimberFill insulation in commercial construction?
Absolutely. TimberFill is well suited for commercial interiors, as well as multifamily housing, schools, and offices. Reach out to our team for assemblies and detailing support.
Is TimberFill fire-resistant?
Yes, TimberFill and all TimberHP wood fiber insulation products are fire resistant. TimberFill is treated with a non-toxic fire retardant and meets ASTM E84 Class A, the highest fire resistance rating for building materials.
What’s the difference between TimberFill and TimberBatt?
TimberFill is a loose-fill and dense-pack insulation alternative for open blow applications. TimberBatt is a batt insulation designed for framed cavities.
We recently completed our first home, insulated with TimberHP. We have been following the development of the company for those last couple years and eagerly awaited the launch of the product. We were excited about TimberHP because it gives us a high-performance insulating package that will allow water to escape and not grow mold or rot the sheathing. An added benefit was the local aspect of the product using a lot of waste material.
Kurt Clason
Clason Remodeling Company – 2022 National Remodeler of the Year
How Can We Help?
Contact Support
Our support team is ready to provide answers to your questions or concerns.
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