Glossary
Deck gap
Also called: board spacing, deckboard spacing, gap
Reviewed
A deck gap is the open space between two neighboring deckboards. With the end boards flush and interior boards equally spaced, the gap is (deck length minus total board width) divided by (number of boards minus 1): a GMA-style 48x40 top deck works out to (48 - 28.5) / 6 = 3.25 in.
How to calculate deck gaps
Gap = (deck length - sum of board widths) / (boards - 1)
| Top deck on a 48 in length | Boards | Gap |
|---|---|---|
| 2 x 5-1/2 + 5 x 3-1/2 in (GMA style) | 7 | 3.25 in |
| 2 x 5-1/2 + 6 x 3-1/2 in | 8 | about 2.36 in |
| 2 x 5-1/2 + 7 x 3-1/2 in | 9 | 1.75 in |
The bottom deck of a stringer pallet uses a different rule: interior boards cluster between the notches, so gaps there are smaller (3.75 in on a GMA-style bottom) with larger openings over the notches.
How big should deck gaps be?
There is no single rule; it depends on the load. palletdesign.ai flags top gaps over 5 in because cartons and bags may sag through, and over 2.5 in under drums, where chimes can drop into gaps. Tighter gaps mean more boards, more board feet and more nails.
Why gaps matter
Gaps under carton walls reduce box stacking strength, and wide gaps let bags bulge and tear. See deck coverage, deckboard and the deck board spacing guide.
Questions
- What is the standard gap between pallet boards?
- On a GMA-style 48x40 top deck the gap is 3.25 in. Other designs vary with the board count and widths.
- How do I reduce pallet deck gaps?
- Add a top deckboard or use wider boards. On a 48 in deck, going from 7 to 9 boards of the same widths shrinks the gap from 3.25 to 1.75 in.