DELTA®-TRELA – Animated Install Sequence


Installation of DELTA®-TRELA water resistive, breathable, sound dampening roof underlayment under a standing seam metal roof. Notice the air circulation and sound dampening characteristics in the final scenes. (Voiceover) 1:33

Step 1: Attach flashing to the edge of the OSB. Nail flashing to roof sheathing. Seal nail holes with caulk or silicon.

Step 2: Ice and water shield should extend at least 2 feet up the roof from the vertical wall intersection point. Check with local building code for requirements.

Step 3: Install DELTA®-TRELA in horizontal runs (i.e., parallel to eaves) with the dimple texturing facing upward and the 4″ (10 cm) edge margin positioned on the side closer to the ridge.

Step 4: When fastening in the field area, use wide-head nails with rubber seals to fix the sheet (included with roll).

Step 5: At the end of the roll, peel and cut off a 4″ (10 cm) wide strip of the air-gap mat to permit overlap at the end of the neighboring roll. Use the same procedure for connections to valleys, dormer windows, etc.

Step 6: X-cut DELTA®-TRELA to fit over smaller protrusions such as plumbing vent stacks, and then fasten/seal directly to the protrusion using either DELTA FLEXXBAND or DELTA-MULTI-BAND, ensuring a secure and water-tight seal.

Step 7: Add a second piece of metal edge flashing over the TRELA, near the eave.

Step 8: Following the manufacturers recommendations, secure the roofing in place.

Step 9: Seal pipe penetration with rubber gasket.

Step 10: Attach the ridge vent and the gutter.

Step 11: Blue Arrows: Air ventilation, Black Arrows: Noise reduction, Red Arrows: Heat reflection