What is a screeding straightedge?

A screeding straightedge (also called a screed board or screed bar) is a straight, stiff and preferably light board or bar used to strike off freshly laid screed, concrete or plaster to a flat surface. Traditionally made of timber, it is now often aluminium. In Dutch the tool is called a “rei” or “reilat”, and in joinery the same word also covers short straight sticks for checking planed boards and a straight rule used for marking out.

Types

• Hand straightedge: a timber or aluminium bar pulled across the material with both hands.
• Power screed: also called a vibrating screed. A vibrating beam that compacts and levels the material in one pass. There are also versions that run on wheels along rails, and floor-screeding robots.
• Angled ceiling straightedge: an L-profile straightedge that catches surplus material when screeding a ceiling.
• Winding sticks: two short, perfectly straight sticks laid across a planed board. Sight across them and you can see straight away whether the board is twisted (in wind).

Application: how to screed

1. Set the level first with screed rails, battens or datum points at the correct height.
2. Place the material slightly high between the rails.
3. Draw the straightedge towards you in a sawing motion. It rides on the rails, not on the material.
4. Fill low spots and strike off again.

Working-conditions rules in the Netherlands

In the Netherlands, an agreement has applied since 1 January 2015 that sand-cement screeds should be laid with a power screed or floor robot wherever possible, combined with task rotation. Where that is technically impossible, the floor must be struck off with an aluminium (or lighter) straightedge, and a maximum area per person per day applies. Self-levelling screeds are not covered. These are Dutch rules; in the UK, your own health and safety legislation applies.

Common mistakes

• Using a bent straightedge. Check it regularly by sighting along it or holding it against a second straight bar.
• Leaving set material on it. Clean it straight after use, or it will no longer be true.

Related terms

• Screeding
• Screed floor
• Poured screed
• Spirit level
• Levelling compound
• Try plane

Want to learn more about construction terms? Visit our knowledge base at fredsdiyplans.com.