TL;DR
Deck board gapping is the spacing left between deck boards, typically an eighth to a quarter inch, so rainwater drains through and boards can move with moisture and temperature swings. The starting width depends on the material's condition: wet pressure-treated lumber gets installed nearly tight because it shrinks as it dries, while kiln-dried wood and composites need their gap built in per the manufacturer's chart, including end-to-end spacing composites require.
What it means
Deck board gapping is the spacing left between deck boards, typically an eighth to a quarter inch, so rainwater drains through and boards can move with moisture and temperature swings. The starting width depends on the material's condition: wet pressure-treated lumber gets installed nearly tight because it shrinks as it dries, while kiln-dried wood and composites need their gap built in per the manufacturer's chart, including end-to-end spacing composites require. Boards laid tight trap debris and water, the recipe for cupping and early rot.
Where it sits in the glossary
Deck board gapping is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
ProFix Directory keeps definitions short on the index page and saves the longer context — Ohio-specific rules, where the term comes from, and which ProFix tools touch it — for these per-term pages so the term is easy to cite and easy to share.
ProFix tools that touch this term
See also
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