Thermwell DAT39H Adjustable Door Threshold 36 Inches

Product Description

The THERMWELL DAT39H is a premium adjustable door threshold designed to seal the gap between the bottom of a door and the floor. Measuring 3.5 inches wide, 0.875 inches tall, and 36 inches in length, this threshold accommodates adjustments of up to 1.3125 inches to compensate for uneven floor surfaces or out-of-square door frames. It is suited for residential and light commercial entry door applications where a consistent, adjustable seal is needed to reduce air infiltration, drafts, and moisture intrusion at the door sill. Installation is typically performed by general contractors, carpenters, or skilled trades professionals handling door and weatherization work.

The DAT39H is designed for use at exterior door thresholds where the floor-to-door gap is irregular or oversized. Its adjustable design makes it a practical solution for retrofit installations where the existing threshold has worn down or where new door installations require fine-tuned sealing at the sill. The 36-inch length fits standard single-door openings. Sold in a package of six units, making it appropriate for multi-unit jobs or stocking for service calls.

Key Features

• Adjustable height accommodates gaps up to 1.3125 inches between door bottom and floor
• 36-inch length fits standard single door openings
• 3.5-inch width provides a stable sill surface and effective sealing footprint
• Designed to seal uneven gaps caused by irregular floor surfaces or door frame settling
• Packaged in quantities of six, suitable for multi-door jobs or service inventory

Compatibility

Designed as an OEM-style replacement or new-install threshold for standard 36-inch exterior door openings in residential and light commercial applications.

Installation Notes

Threshold installation is typically performed by carpenters, general contractors, or weatherization technicians. Remove the existing threshold and clean the sill surface before fitting the new unit. Adjust the threshold height using the built-in adjustment mechanism to achieve a consistent seal against the door bottom before final fastening. Follow local building codes for weatherproofing and accessibility requirements at exterior door thresholds.