Palladian    One central arch-headed window flanked by two narrower, shorter, arch or square-headed windows
Pallet    A wooden platform used for storing and shipping bundles of shingles.
Parapet    A wall placed at the edge of a roof, usually a flat roof for a finished look or for safety of people. Minimum height is governed by code.
Payment schedule    A pre agreed upon schedule of payments to a contractor usually based upon the amount of work completed. Such a schedule may include a deposit prior to the start of work. Payments are often scheduled for the beginning of the month and allow the contractor to subcontractors and suppliers by the 10th of the month. There may also be a temporary 'holdout' at the end of the contract for any small items which have not been completed.
Pediment    A low-pitched gable above a portico (above a door or window)
Permit    A governmental authorization to perform a building process.
Pilaster     - A structural column that is rectangular in plan and that usually projects a third of its width or less from a wall
Pitch     1. The degree of roof incline expressed as the ratio of the rise, in feet, to the span, in feet. See also slope. 2. A thick, oily substance commonly obtained from tar, used to seal out water at joints and seams. Pitch is produced from distilling coal tar, wood tar, or petroleum.
Pitch pan or Pitch pocket    A container, usually formed of sheet metal, around supporting connections with roof-mounted machinery. Filling the container with pitch, or better yet, plastic roof cement, helps seal out water even when vibration is present.
Plate    The 2x4's placed on top of studs. It is the top horizontal member of the wall upon which joists and rafters rest.
Plans    Scaled drawings showing elevations, floorplans, details, and written specifications. In larger projects, separate sheets are included for architectural, structural, mechanical, electrical, civil and landscape. Plans are approved by the building official for issuance of a building permit. The plans are incorporated into the prime contracts together with the specifications and other contract documents.
Plastic roof cement    Ultimate protection for those tough jobs is found in this specially formulated heavy-bodied material. Used as a waterproofing medium in new construction and as a general-purpose exterior repair and maintenance material. Stops roof and other leaks fast. Available in both summer and winter grades.
Plumbing permit     - a separate permit required for new plumbing and larger modifications of existing plumbing systems.
Ply    The number of layers of roofing; i.e. one-ply, two-ply.
Ply sheet    A layer in built-up roofing.
Portico     - A roofed space open or partly enclosed, often with detached or attached columns
Post    A vertical framing member usually designed to carry a beam. Often a 4" x 4", a 6" x 6", or a metal pipe with a flat plate on top and bottom.
Post and beam      Method of construction using vertical members (posts) to support load-bearing horizontal members (beams).
Pressure relief Vvlve    A device mounted on a hot water heater or boiler which is designed to release any high steam pressure in the tank and thus prevent tank explosions.
PVC or CPVC    A type of white plastic pipe sometimes used for water supply lines.