Support Spacing
Confirm support spacing for the selected profile, orientation and interior or exterior condition.
THERMOStart your projectBUILDERS FIRSTSOURCE · ISSAQUAHGet a local Maximo consultation
Overhead Architectural Finishes · Division 09 54 23 · Issaquah project guide
Thermo Ashfor Ceilings & Soffits.
Thermo Ash brings hardwood warmth and strong grain contrast to covered soffits, entry portals and interior vaulted ceilings. End-matched profiles can simplify joint alignment across long overhead runs when installed to the profile instructions.
APPLICATION SYSTEMThermo Ash · Ceilings & Soffits
1,320Janka Hardness
38.5Dry Density
Verify ProductDurability Rating
20 YearMaximo Warranty
Hardware & Nails
Use the stainless fastener type and placement allowed by the current profile instructions.
Sub-framing Details
Provide a continuous, level and adequately supported attachment plane.
Air Cavity Specs
Coordinate exterior soffit ventilation with the roof and wall assembly design.
Material & assembly planning
Key advantages &
installation rules.
Material Continuity
Use the same species across interior ceilings and covered exterior soffits when each assembly is detailed for its exposure.
Reduced Resin Movement
High-temperature processing reduces volatile resins and pitch compared with untreated material.
Defined Shadow Lines
The cataloged profiles create a repeatable joint expression when installed on a level support plane.
Assembly Guidelines for Ceilings & Soffits:
- Acclimate ceiling boards within the conditioned space for 48 hours prior to interior installation.
- Coordinate lighting, speaker penetrations, and ventilation grilles with board centerlines.
- For exterior soffit returns, maintain 1/4" perimeter clearance to accommodate subtle building structural movement.
Reduced tangential movement supports more consistent joints through seasonal changes.
Thermal modification reduces moisture uptake and changes nutrients used by decay fungi; confirm the rating for the selected profile.
Real wood modified without added wood-preservative chemicals.
Consultation and order coordination through BFS Issaquah.
Cataloged Profiles
2 Profiles available for
Thermo Ash ceilings & soffits.
5/4x6S4S E4E End MatchWhere to buy in Issaquah
Builders FirstSource Issaquah
Catalog available by consultation. Contact the Issaquah team to confirm availability, sample kits, and lead time for your selected Maximo profile.
Issaquah, WA 98029
(425) 391-8000
Monday–Friday, 7:00 AM–4:00 PMDealer information verified August 31, 2026. No in-stock claim is made on this site.
Request a local quote
Put this profile
on your project.
Tell us what you are building. Our team will review your wood selection and contact you to coordinate a Maximo consultation with Builders FirstSource Issaquah.
Frequently Asked Questions
Thermo Ash · Ceilings & Soffits
Will Thermo Ash soffits sag over 16" on-center framing?+
Do not assume a deflection-free span from the species alone. Confirm the selected profile, support spacing and fastening method with the current Maximo instructions and the project designer.
Product and installation references