Metal Roof Underlayment Requirements

Roofing underlayment roofing felt requirements.

Metal roof underlayment requirements.

We recommend a polypropylene scrim reinforced underlayment made up of multiple layers. 12 roofing underlayment wind by mcm best roof underlayment for tile roofs. Power driven metal caps shall have a minimum thickness of 0 010 inch. We generally prefer the use of synthetic underlayment as it is more durable and will last longer.

Make sure the product is designed to be used under metal. Traditionally metal roofs have used standard 30 pound felt paper underlayment. How well roof underlayment performs will depend on which type you use. For architectural metal roof panel systems a roof underlayment is required to help control water leakage through the roofing system during heavy rain storms or under snow melting conditions.

Whether you re opting for a traditional underlayment or a selfadhered option the average life span of a metal underlayment will vary depending on the product that s selected. Minimum thickness of the outside edge of plastic caps shall be 0 035 inch. This type of underlayment is critical to a quality roof installation. Becoming familiar with the metal roof underlayment options available can help you decide what s best for your commercial building.

The first goal of roofing underlayment is to keep the roof deck dry before installation of the metal roofing material. 10 roof protector underlayment roll best roof underlayment for metal roof. Felt details for various roof slopes amp. 13 1 frequently asked questions.

This article series discusses roofing felt specifically addressing the roofing code or roofing manufacturer s requirements for use of an underlayment such as roofing felt tarpaper or other underlayment products beneath asphalt shingles and other. Metal caps shall have a thickness of at least 32 gage sheet metal. Underlayment must also act as a secondary weather barrier in case the roof fails. It serves as a moisture barrier as well as a slip sheet.

Is roofing felt required. Underlayment shall be attached using metal or plastic cap nails or cap staples with a nominal cap diameter of not less than 1 inch. At western states metal roofing we have been in the roofing industry for over 20 years and have encountered every type of scenario with both types of underlayment. Overhang the roof rake edge 1 5 and cover the underlayment with a metal rake edge trim.