Perpend
The term ‘perpend’ (perp or cross joint) refers to the vertical joints between blocks or bricks that have been laid in a horizontal course to form a wall. Perpends are normally filled and sealed with mortar. The horizontal mortar joint in a wall construction is typically referred to as the bed joint.
Rather than being filled with mortar, perpends may also be left open to form weep holes or cavity ventilators. These provide openings that allow the drainage of moisture from within a wall construction and allow ventilating air to the back of a wall to help prevent mildew, dry rot and damp. They are generally formed by plastic inserts into the perpends, as these form a more uniform opening compared to simply leaving a void. See weep holes for more information.
A perpend stone is a long stone that extends between the inner and outer layers of a stone wall, tying the two layers together. The stone is ‘dressed’ at both ends.
The term ‘perpend’ may also be used more generally to refer to any brick or stone the longest dimension of which is perpendicular to the face of the wall. See bond stone.
The expression “keeping the perpends” is a term used to describe what happens when cross joints or transverse joints in brickwork are maintained in a perpendicular line.
[edit] Related articles on Designing Buildings Wiki
Featured articles and news
Future proofing homes that are fit for purpose
Specification challenges and the role of plastic.
Thousands of new homes unlocked for brownfield sites
£68 million to 54 councils for neglected land into new homes.
Roof terraces and higher-risk buildings
Context, review, interpretation, case and guidance..
Sustainable Futures. Redefining Retrofit for Net Zero Living
More speakers confirmed for BSRIA Briefing 2024.
Architecture in Britain and Ireland, 1530 - 1830
Steven Brindle’s book is required reading.
Employment Rights Bill; making work pay
‘Biggest uplift in employment rights law since the 1970s’
Battle for Mill Road Free Library
Years of failures by the county and city councils.
The accolades that demonstrate and recognise outstanding achievement.
What is the Conference of the Parties ?
The who, where, what and when before no 29.
CIOB signs up to Green Skills At COP campaign
In preparation for COP29 on 11 November in Azerbaijan.
2024 ECA Industry Awards evening
Full list of electrical contractors scooping top prizes.
Briefing on the implications of the final Grenfell inquiry report
What it means for Architectural Technology professionals.
CIOB Art of Building photo contest 2024
International showcase for the very best photography of the built environment.
Celebrating architecture's eloquent champions.
Unusual perspectives on 1960s’ thinking.