Description

Double Hung Window With Transom Features

Our double hung windows with transoms combine ​historic craftsmanship and ​modern airflow optimization, designed for enhanced light and ventilation. Featuring vertical-grain Douglas fir or thermally modified oak frames (1.75″ thickness, ASTM D1037 compliant) paired with fixed/operable transoms, these units deliver:

​Stack ventilation system – Simultaneous upper/lower sash operation creates 42 CFM airflow, amplified by transom chimney effect
​Architectural authenticity – 7/8″ true divided lites with 6-over-6 grille patterns (National Park Service compliant)
​Hybrid glazing – Low-E insulated glass (U-factor 0.27) in main sashes + frosted transom panels for privacy

Technical innovations include:
​Integrated transom design – 12″-36″ height transoms with ±1/8″ tolerance for historic retrofit
​Thermal break – Aerogel-insulated frame cavities reduce heat transfer by 48%
​Dual drainage – 7° sloped transom sill redirects 2.8 GPM water flow.

Benefits of Double Hung Windows With Transoms

1. Enhanced Climate Control
​Seasonal adaptability – Open transoms in summer for cross-breezes (+18% airflow), close in winter for heat retention
​Humidity management – Tilt-in sashes clear bathroom steam 22% faster than standard models.

2. Historic-Modern Fusion
​Style continuity – Replicate Victorian/Colonial transom profiles (FSC-certified woods)
​Custom configurations – Mix operable transoms with fixed art glass (60+ leaded designs)

3. Maintenance Efficiency
​Full-access cleaning – Removable sashes + inward-tilting transoms enable exterior cleaning without ladders
​Self-lubricating tracks – PTFE-coated channels maintain smooth operation for 30+ years.

4. Energy-Smart Design
​Solar modulation – Transom placement blocks 73% midday UV while allowing morning light (SHGC 0.19)
​Airtight seals – Triple weatherstripping achieves <0.12 CFM infiltration (exceeds ENERGY STAR® by 28%)

5. Security & Compliance
​Child-safe transoms – Keyed locks restrict openings to 4″ (ASTM F2090 compliant)
​Egress readiness – 20″x36″ main sash opening meets IRC R310 emergency standards.