Components
What is a putlog?
A putlog is a horizontal tube with a flattened blade at one end, built into the brickwork of a wall to support the inner side of a putlog scaffold.
Use this diagram+
Free to use on your own site, in training material or in a course handout, as long as the credit link stays on it. Paste this where you want the diagram to appear.
<figure>
<img src="https://scaffoldoptix.co.uk/glossary/putlog/diagram.svg" alt="putlog — scaffold diagram from ScaffoldOptix" width="880" height="620" loading="lazy">
<figcaption>
<a href="https://scaffoldoptix.co.uk/glossary/putlog">What is a putlog?</a> — diagram by
<a href="https://scaffoldoptix.co.uk">ScaffoldOptix</a>
</figcaption>
</figure>The blade sits in a bed joint as the brickwork goes up, so the wall supports one end and a single row of standards supports the other.
It is the member that gives the putlog scaffold its name, and the reason that scaffold type needs brickwork rather than any wall.
On an independent scaffold there are no putlogs — the equivalent member is a transom, carried on ledgers at both ends.
What goes wrong on site
- Called a transom, or vice versa, which obscures whether the building is carrying load.
- Removed during pointing or repair without anything replacing the support.
- Blades bearing in a joint that has not set.