CSLB General Building (B)Site Work, Foundations and ConcreteEasy
Before excavation begins on a new residential foundation, a surveyor sets up wooden batter boards with string lines at each corner of the building. What is the main purpose of batter boards?
- ATo establish and preserve reference points for building corners and lines after excavation begins
- BTo anchor the vapor barrier before the slab is poured
- CTo support formwork during the concrete pour
- DTo provide temporary shoring for the excavation walls
Show answer & explanationAnswer & explanation
Correct answer: A. To establish and preserve reference points for building corners and lines after excavation begins
Batter boards are set back from the excavation area with string lines strung between them to mark building corners and layout lines. Because excavation disturbs the ground, batter boards allow the crew to re-establish exact corner locations throughout construction.
Why the other options are wrong
- B. Vapor barriers are secured separately and unrelated to layout batter boards.
- C. Batter boards are a layout tool, not structural formwork support.
- D. They are unrelated to trench wall shoring or soil protection.
Batter Boards
Temporary wood frames set outside excavation limits with string lines used to mark and re-establish building corners and reference lines during construction.
- Placed outside the excavation area so they aren't disturbed
- String lines mark exact building corners
- Allow layout to be re-checked throughout construction
Memory trick: Batter boards hold the strings that never let the corners go missing.