T-square
A T-square is a t-shaped guide that can be used to draw horizontal and vertical lines perpendicular to a straight edge. This can be useful in the manual drafting of drawings.
The shorter ‘top’ part of the T (sometimes referred to has the head or stock) protrudes down from the surface of longer ‘blade’ of the T-square and can be pushed against the straight edge of a board such as a drawing board and moved up and down, providing a guide for drawing lines. It can be used in conjunction with other devices such as set-squares to draw lines that are not parallel to the edges of the board.
T-squares can offer a simple alternative to parallel motions, which are built into more sophisticated drawing boards.
T-squares are typically made from wood or metal and may include markings to allow measurement.
T-squares may also be used in construction for marking out lines perpendicular to the edges of boards such as plasterboard to ensure accurate cutting.
[edit] Related articles on Designing Buildings
- Blueprint.
- Drawing board.
- Manual drafting techniques.
- Model.
- North American Paper Sizes
- Paper sizes.
- Parallel motion.
- Perspective.
- Projections.
- Scale drawing.
- Scale rule.
- Scale.
- Symbols on architectural drawings.
- Technical drawing pen sizes.
- Technical drawing.
- Techniques for drawing buildings.
- Types of drawing.
Featured articles
Check out some of the best features and news from Designing Buildings as well as key stories from around the web.
New and updated CLC building safety guidance.
New UK National Buildings Database.
Building Safety Wiki Interviews
Chief executive of the British Woodworking Federation.
Planning condition discharge in England and Wales
A brief explanation from a building compliance expert, with further links.
Overheating guidance and tools for building designers
Guidance for dealing with element of building fabric control that have increasing importance.
Shading for housing, a design guide
From the Good Homes Alliance and British Blind and Shutter Association.
UK Standard Skills Classification (SSC)
A shared framework for describing skills needs.
Social media ban consultation comes to close
CIOB urges UK Government to consider social media’s role in careers guidance in ban debate.
The latest of eight Skills England apprenticeship units
The addition of battery manufacturing welcomed by ECA with a warning about the risks of fast-tracked apprenticeship units.
Building Control Independent Panel final report
A precis of a key report led by Dame Hackitt with full recommendations and link to the government response.
Building Safety recap April, 2026
A short and longer run-through of the month, with links to further information and sources.
















