Straightedge A long, rigid tool made of wood, aluminum, or magnesium used to check the flatness of a concrete surface and guide screeding operations.
A high-quality straightedge is critical for verifying that a newly poured sidewalk meets ADA flatness and slope standards. NYC DOT regulations have zero tolerance for sudden grade changes or localized depressions that can catch water. Contractors run a straightedge across the freshly screeded concrete to identify any high spots that need shaving or low spots that require filling, ensuring a smooth, continuous path for pedestrians and wheelchair users.
Frequently Asked Questions About Straightedge
What is a straightedge used for?
Checking the flatness of a concrete surface and guiding screeding, by revealing high and low spots against a true line.
Why does flatness matter?
Localized depressions collect water and abrupt grade changes create trip hazards, both of which can be cited.
How is it used on a finished slab?
It is laid across the surface in several directions, and any gap beneath it shows a low spot that needs correction before the concrete sets.
Does it help with accessibility compliance?
Yes. It is the practical way to verify the surface has no abrupt level changes along an accessible route.