SIMPSON DOORS AT ASHBY LUMBER
At Ashby Lumber, we proudly offer Simpson Door Company® products—crafted for beauty and built for performance. With over a century of craftsmanship behind every door, Simpson® continues to set the standard for timeless design, lasting durability, and architectural versatility. Whether you’re enhancing curb appeal or upgrading your interior spaces, Simpson® delivers solid wood and wood-based doors that marry artisanal quality with modern performance. Let our team help you find the perfect fit for your home or project.
Why Choose Simpson Door Company® at Ashby Lumber?
Craftsmanship
Since 1912, Simpson® has set the standard in solid wood door construction, blending artisanal skill with precision engineering for long-lasting beauty and performance.
Design Options
Whether you need a striking entry door, a Dutch door for charm, or a modern interior look, Simpson® offers hundreds of customizable styles, wood species, and glass inserts to match your architectural vision.
Performance
Advanced door technologies like WaterBarrier® and UltraBlock® dramatically improve weather resistance, moisture protection, and overall durability—ideal for coastal or high-exposure applications.
Sustainability
Simpson® doors meet or exceed environmental standards, including CARB Phase 2 compliance and low-VOC adhesives. Safety-tested glass and fire-rated door options ensure peace of mind in any setting.
Exploring Simpson Door Company® Solutions
Performance Series®
WaterBarrier® & UltraBlock®
Water Protection: WaterBarrier® full-surface sealant prevents moisture intrusion
Reinforced Structure: UltraBlock® composite blocks in stiles/rails resist rotting
Weather Seals: Joints are coated and bonded to minimize water infiltration
Exposure-Ready: Guaranteed performance even without overhang
Durability: WaterBarrier® and UltraBlock® doors carry a 5-year enhanced warranty
Warranty: 5-year component warranty applies to WaterBarrier® or UltraBlock®- equipped doors
Standard Coverage: Other door parts retain a 1-year limited warranty
Installation Guidance: Must be properly sealed, finished, and hung—see Care & Finishing
Nantucket Collection™
Mortise-and-Tenon Joinery: Traditional joinery with optional joinery pins or pinless groove
Durable Wood Species: Douglass Fir, Sapele, Nootka Cypress, Western Hemlock, or Accoya
Premium Glazing: Includes 3/4″ insulated glass with SDL options for energy efficiency
Worry-Free Exposure: Engineered to withstand extreme climates—no overhang needed
Aesthetic Continuity: Pinless design option offers clean lines for seamless indoor-outdoor flow
Warranty: 10-year full-door warranty applies to properly sealed and finished doors
Natural Characteristics: Face-checking is normal; not considered defect
Coverage Limit: Applies only to the original homeowner; no transfer for commercial use
Interior Doors Collection
Solid or Engineered Cores: Options include thick 1/16″ veneer standard, upgradeable to 1/8″ or 1/4″
Panel Variety: Thousands of styles—French, flat-panel, shaker, barn, fire-rated
Stability Standard: Built to NWWDA I.S.6 for consistent interior performance
Fire-Rated Options: Up to 90-minute ratings while matching interior panel styles
Warranty: 10-year interior warranty for residential use, properly finished and installed
Exceptions Apply: Reduced to 1-year for fire-rated, resin panels, or commercial use
Original Homeowner Only: Warranty is non-transferable
Glazing: Insulated & Leaded Glass
Energy Glass Options: Clear, Low-E, argon-filled insulated glass units
Safety Compliance: All glazing meets ANSI Z97.1/CPSC standards; tempered or leaded as required
Hermetic Seal Guarantee: Insulated glass unit maintains seal; max air leakage ≤0.0 inswing/0.04 outswing
Warranty: 5-year IG seal warranty protects against vision-obscurring seal failure
Lead Glass Sealed: Also covered under 5-year hermetic seal warranty
Why Choose Ashby Lumber?
At Ashby Lumber, we don’t just supply materials—we provide solutions. Our expert team is here to guide you through the process, ensuring you select the perfect Therma-Tru products for your project. With decades of experience serving Bay area homeowners, contractors, and builders, we’ve earned a reputation for exceptional service and quality.
Transform Your Space with Simpson® Products From Ashby Lumber
Visit us at our Berkeley or Concord locations, or contact us to schedule a consultation with our experienced team. Let us help you bring your vision to life with Simpson Door Company®’s exceptional products.
As a leading provider of doors and windows in Berkeley, Concord, and the wider East Bay, Ashby Lumber is dedicated to helping you find the perfect solutions for your home or project. Our Berkeley and Concord showrooms feature a curated selection of high-performance entry and interior doors, including designs that combine timeless craftsmanship with enduring quality.
We’re proud to offer Simpson Door Company®, a brand with over a century of experience handcrafting solid wood doors that are both beautiful and built to last. From the refined, traditional styling of the Nantucket Collection™ to the weather-resistant innovations of the Performance Series®, Simpson® delivers an unparalleled range of design choices and wood species—each engineered for strength, character, and long-term performance. Whether you’re designing a grand entryway, a cozy interior, or a high-exposure exterior upgrade, our expert team is here to guide you every step of the way—ensuring your door not only enhances your home’s style but stands the test of time.