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Short Summary
Main recommendation: For a wheelchair-accessible ground-level deck where the city will not allow digging footings, build a freestanding floating deck on a level base of deck blocks and 2x8 lumber, then connect the joists to a galvanized-bolted box beam rather than relying on screws for load-bearing. The video walks through leveling the base on sloped clay ground, installing joist hangers, and choosing structural fasteners.
Key Points
- The city allowed a floating (non-excavated) deck for this wheelchair ramp instead of 24x24-inch footings dug 5 feet deep, which the clients were quoted at roughly $40,000 for excavation.
- The floating deck is a freestanding structure not attached to the house, which is what made the surface-based design acceptable to the city.
- The base is leveled on deck blocks because the ground is sloped and the deck settled slightly while working from it.
- Screws have very low shear strength (about 50 to 70 pounds per screw), so load-bearing connections use galvanized bolts, nails, or structural screws rather than standard screws.
- Landscape cloth (contractor grade, rated 25 to 30 years) is laid under the deck and covered with gravel to prevent plant growth through the structure.
Details Worth Noting
- Concrete instructions: Lay out contractor-grade landscape cloth, overlapping seams 4 to 5 inches, and cover the seams with gravel.
- Concrete instructions: Set deck blocks on the leveling layout lines, using two 2x8 boards and four deck blocks across the back for the base; add extra blocks to reduce deflection on the large flat surface.
- Concrete instructions: Where the ground is uneven, use a post and block with screws to achieve a level structure instead of adding limestone screenings.
- Concrete instructions: Drill a 1/2-inch hole through the 4x4 and 2x8 connection, insert a galvanized bolt, nut, and washer, tighten by hand, then wrench-tighten and seat the washer into the wood.
- Concrete instructions: Use screws only for temporary setting of joists; install joist hangers on the top of the wood, flip them to position the joist, and screw them in together.
- Concrete instructions: Where bending loads occur (such as the platform), use nails or structural screws rather than standard screws; overlapping joists on a box beam with galvanized bolts carries the weight directly, so fastener choice matters less.
- The speaker mentions Simpson Strong-Tie structural screws as a product he uses for bending-load connections, noting they are strong steel with shear strength comparable to nails and easy to install with a screw gun.
- The project was noted as requiring the platform to be finished before the ramp and deck; after the platform and layout for stairs/ramp are done, the next step is calling for inspection.
Bottom Line
Freestanding floating decks can replace costly excavated footings when local code allows it, but their stability depends on a carefully leveled base and the correct fasteners for each load type.
