Roof Underlay

Felt underlayment is a particularly common type in Australia. It is cost-effective and quick to install, providing adequate reinforcement. This is the recommended type for metal roof underlayment. In some roof assemblies, an insulation blanket for roof construction is installed with the underlay to provide thermal protection.

Often preferred by professionals, the slightly more expensive synthetic underlayment boasts a higher strength than other types and will require less upkeep over time.

The right kind of roof underlay will provide a high level of protection against the harsh climate in Australia. Often, roofs with improper underlay experience greater shingle loss and damage, which requires a high cost in restoration and repair. Additionally, underlay avoids water absorption, improving the longevity of the roof as the exterior materials and framework will not become brittle with water exposure. Importantly, roof underlay behaves as a barrier between the home and any adverse weather conditions, including rain, humidity and snow.

The best roof underlay for your home will depend on the conditions of your region and the slope of your roof. While all underlay offers protectivity and enhances the longevity of your roof, some are better suited to particular functions than others. Synthetic underlayment, particularly non-bitumen types, are highly water and UV-resistant, meaning it will remain intact in areas exposed to excessive heat, as is common in Australia. Steep-sloped roofs, on the other hand, require asphalt-saturated felt to ensure sufficient water runoff. For tiled roofs, choose an underlay specified beneath the roofing tile layer so water can drain towards the eaves.