Guide
Can you build a deck on deck blocks?
Freestanding ground-level decks on concrete deck blocks: sizes, joists and the typical permit exemption.
| 12 ft wide deck | Joists | Deck blocks | Materials |
|---|---|---|---|
| 12′ × 6′ | 2×6 pressure-treated | 6 | ~$597 |
| 12′ × 8′ | 2×6 pressure-treated | 6 | ~$679 |
| 12′ × 10′ | 2×6 pressure-treated | 6 | ~$812 |
| 12′ × 12′ | 2×8 pressure-treated | 6 | ~$952 |
- Typical exemption: ≤ 200 sq ft, ≤ 30″ above grade, freestanding
- Above 30″ a deck needs railings and usually a permit: not covered here
Numbers computed by the same engine that writes the plans. Typical values; your town and your materials may differ.
Questions
Do I need a permit for a deck on blocks?
Often not when it is 200 sq ft or less, 30″ or less above grade, freestanding and not at an exit door. Your town decides.
Do deck blocks need footings below frost?
Not usually for freestanding decks, but some towns require it. Ask before you build.