19Apr/16

Starter Shingles

The first course of roofing installed. Sometimes trimmed from main roof material.

19Apr/16

Waterproof Underlayment

Modified bitumen based roofing underlayments.  Designed to seal to wood decks and waterproof critical leak areas.  Also known as ice and water shield.

02Apr/16

Valley

The internal intersection of two sloping roof planes that runs from the eaves to the ridge. This intersection collects the most water run-off. See Open Valley, Closed-Cut Valley, and Woven Valley.

01Apr/16

PVC

See Polyvinyl Chloride.

01Apr/16

Purlin

Horizontal secondary structural member used to transfer loads from the primary structural members.

01Apr/16

Puncture Resistance

The ability of a material to withstand being pierced by a sharp object.

01Apr/16

Psychrometer

An instrument that uses the difference in readings between two thermometers, one having a wet bulb and the other having a dry bulb, to measure the moisture content or relative humidity of air.

01Apr/16

Protected Membrane Roof (PMR)

A roof assembly in which the insulation and ballast are placed on top of the membrane component. Commonly referred to as an “inverted roof assembly.”

01Apr/16

Proportioner

A pumping unit comprised of two (2) positive displacement pumps that is designed to dispense two (2) components at a precise ratio. Used in SPF and plural component coating applications.

01Apr/16

Primer

A material that is applied to a surface in order to increase that surface’s ability to adhere to or work in conjunction with a subsequently applied material.