Pins or pinning
(Scots): Lines of tiny stones used decoratively in the mortar joints.
Walling material of clay mixed with straw. Also called cob.
In a church or chapel, a basin for washing Mass vessels, provided with a drain, usually set in or against the wall to the south of an altar.
Pitchback water wheel
One with water fed on to the wheel on the top but falling backwards. Compare breastshot, overshot and undershot.
Pitched masonry
Laid on the diagonal, often alternately with opposing courses (pitched and counterpitched, also called herringbone).
Pit prison
(Scots): Sunk chamber with access from above through a hatch.
Place bricks
The poorer kind of bricks, used on internal or concealed construction. Compare stock bricks.
Flat plain horizontal course or moulding between storeys.
Longitudinal member of a timber-framed building, set square to the ground.
Plate girder
A girder of I-section, made from iron or steel plates.