The pressure of water as measured at a stated point, either in feet or in pounds per square inch (PSI).
Head plate
Also called a wall plate, this horizontal structural piece is anchored to a masonry wall. Other structural pieces may be supported from it.
Head pressure
Maximum amount of pressure against which a pump can move fluid.
Header
(1) A beam running perpendicular to the studs or joists to which joists are nailed in framing of stairways, chimneys, etc. (2) Top horizontal piece, often made of boards nailed together, which serves as the top section of a window or door. (3) Horizontal framing member to which the ends of the joists are nailed. (4) A short section of brick or a brick laid so the end is to the wall surface. (5) Also, a masonry unit that ties together different vertical masonry sections.
Header flare
Exposed header, which is painted noticeably darker than the others.
Header or heading, course
Course of brick which is set with the end of the bricks facing outward.
Header, blind
Brick header that is concealed.
Header, clipped
Also referred to as false header, brick is cut, up to half its size, to set up a pattern.
Heading back
Cutting an older branch or stem back to a stub or twig.
Headlap
The distance that the topmost ply of roofing felt overlaps the undermost ply or course.
