The P20 delivers 20-minute fire protection with particle board core construction at 1-3/4 inches thick. Built for residential hallways, bedrooms, stairwells, and light commercial spaces where fire ratings matter, this door handles code compliance without overengineering. The particle board core provides dimensional stability that hollow-core doors can’t match, while the customizable face finishes let contractors match any interior design.
Fire Rating and Core Construction
The P20 carries a 20-minute fire rating certified to UL/ASTM standards, meeting code requirements for most residential and light commercial applications. These fire doors are tested and certified under standards including CAN/ULC-S104, UL 10(b/c), and NFPA 252, with Category B positive pressure certification.
The particle board core construction delivers more than just fire resistance. The solid core uses a drop-in loose-lay format that provides consistent density throughout the door. This translates to better sound dampening than hollow-core alternatives — critical in multi-family housing where noise transmission between units matters.
| Specification | Value |
|---|---|
| Fire Rating | 20 minutes |
| Core Material | Particle board (solid core) |
| Thickness | 1-3/4 inches |
| Certification Standards | UL 10(b/c), CAN/ULC S104, NFPA 252 |
| Pressure Category | Category A and B positive pressure |
| Warranty | 1-year limited (interior use) |
The core comes in bonded/sanded or loose-lay configurations, giving fabricators flexibility in finishing options. While the manufacturer doesn’t specify exact weight in current literature, particle board cores typically run 4.5-5.5 pounds per square foot — heavy enough to feel substantial but manageable for installation crews.
Customization and Applications
The P20’s versatility shows in its face finish options. Wood veneers, molded profiles, and hardboard finishes let contractors match existing millwork or create specific aesthetics. Additional options include architectural wood veneer, high-pressure laminate, and factory glazing.
The door accommodates ventilated (VanAir) configurations for mechanical rooms or areas needing air transfer. Lead-lined options handle x-ray room requirements in medical facilities — a growing market in Montana’s expanding healthcare sector.
Application flexibility extends beyond basic passage doors:
- Residential interior doors where fire rating is required (hallways, bedrooms, stairwells)
- Light-commercial projects including schools, offices, healthcare facilities, and retail
- Interior passage and bifold door applications
Maximum dimensions reach 3’0” width and 7’0” length for single swing designs, covering standard residential openings. Hardware options include cylindrical or mortise locksets, deadbolts, fire exit devices, automatic door bottoms, closers, protection plates, and viewers — all requiring fire-rated listings.
The P20 fills the gap between non-rated particle board doors and heavier commercial fire doors. For Montana’s growing multi-family housing market — particularly in Kalispell and Missoula — these doors meet fire separation requirements without the cost premium of 45- or 60-minute rated doors where codes don’t require them.
Installation and Compliance
The P20 follows standard interior door installation procedures, with no special framing requirements beyond typical fire door practices. Lynden Door provides specific ‘Hardware Preparation’ and ‘Handling Guides’ for field installation, plus a ‘Jobsite Storage and Handling Guide’ for the Standard Construction series.
Installation must follow manufacturer instructions and be performed by qualified personnel. Final acceptance depends on local authorities having jurisdiction (AHJ) — critical in Montana where building departments vary county by county.
Environmental compliance matters for indoor air quality. The P20 meets CARB Phase II (low-VOC) compliance and TSCA Title VI (formaldehyde emissions) compliance, addressing concerns in tight modern construction where air exchange rates run lower.
As part of the Standard Construction (SD) line with a 1-year warranty, the P20 positions itself for projects needing reliable fire protection without architectural-grade pricing. The door competes directly with similar 20-minute particle board offerings from Masonite and Jeld-Wen but brings Lynden Door’s reputation for consistent core quality.
FAQs
What’s the actual weight of a P20 door? While Lynden Door doesn’t specify exact weight in current literature, particle board cores typically weigh 4.5-5.5 pounds per square foot. A standard 3’0” x 6’8” door runs roughly 80-100 pounds — manageable for a two-person crew but substantial enough to hang properly.
Can the P20 handle bathroom installations? The P20 works for bathrooms as a fire-rated option, though ventilated (VanAir) configurations provide better air circulation for moisture control. The particle board core requires proper bathroom ventilation to prevent moisture damage over time.
How does the P20 compare to Lynden’s other fire-rated options? The P20 is the 20-minute fire-rated version of the standard P4 (1-3/4” non-rated particle board) door. It provides superior weight and sound dampening compared to hollow-core H4 doors while staying in the affordable Standard Construction line rather than stepping up to Commercial or Architectural series.
What hardware works with the P20? The door is compatible with standard interior door hardware packages and various lockset/hinge configurations. All hardware must be listed and labeled for fire safety — standard residential hardware won’t meet fire door requirements.
Ready to Get Started?
Our doors & millwork specialists can help you find the right Lynden Door products for your project.
More from Lynden Door
Explore All Lynden Door Products
We carry Lynden Door across all 11 Montana and Idaho stores.
