DELTA Trela

The Problem

Metal roofs and cladding are not sealed to the roof deck or sheathing, allowing moisture to easily get underneath the metal. If moisture is allowed to accumulate under the metal, two problems arise: it can prematurely damage the roof substructure (requiring removal of the metal and repair), and it can condense on the underside of the metal, leading to corrosion and premature replacement.

The Solution

DELTA-TRELA is a vapor-permeable underlayment with structured separation and drainage, specifically designed for metal roofs and facades with metal cladding. The underlayment prevents corrosion and moisture accumulation underneath panels, ensuring the longevity of your metal roof.

Product Details

• 8 mm-high randomly oriented studded fiber mat
• Fiber mat is thermally bonded to a vapor-permeable, watertight fabric, based on DELTA-VENT S

Product Benefits

• 8 mm studded fiber mat ventilates the underside of metal panels
• Drainage course studded structure reliably channels residual moisture to the exterior
• Vapor-permeable, watertight fabric ensures airtightness and allows moisture within the roof cavity to escape via diffusion
• Reduces rattling noise from rain or hail by up to 15 dB
• Installed parallel to the eaves, with the studded structure facing upward; the next section of membrane overlaps in shingled fashion to shed water to the exterior
• Burled, studded texture provides a non-slip surface during installation
• One-step installation is faster and easier than applying an underlayment and a separation layer in independent steps

Install with DELTA Sealing Nails, sold separately in boxes of 120.