Floating decks in Guelph–Grade Beam Foundations
Floating decks are simply decks that do not have below grade footings. This red cedar deck was built in Guelph Ontario and was built using a grade beam foundation. Rocky soil and the fact that they excavate all the yards down 8′ play havoc with footings. All the fences in the area were shifted and not plumb. This was pre-helical footings days, so we came up with a floating footing for decks. The soil is expected to settle for the next 30 years or so. Floating footings are those that rise up and down with the frost, and in theory, they should settle to much the same level as they were previously. Since the floating slabs move, the deck is not connected to the house.
Designing Floating Decks
Floating decks cannot connect to the home in frost prone areas. The frost can lift the deck and potentially cause damage to the home. This one was built for a future hot tub. It was framed to make it easy to remove part of the deck where the hot tub will be. The support slab for the tub is already in place. We designed a simple pergola to offer vertical interest to this very cool deck design.
Grade Beam Floating Decks: Pros
- No Permits Required.
- Does not need to conform with Zoning–seen as a patio.
- About the same budget as a Helical Foundation.
- Stays more level than sonotube foundations in excavated soil.
- No need for a beam within deck frame–foundation is the beam.
- Stays much more level than deck blocks.
- Good solution for ground level decks–buried beams tend to rot.
Grade Beam Floating Decks: Cons
- May settle slightly over time.
- Not easily adapted to higher decks.
- Requires concrete forming and finishing ability.
- Takes longer than Helical Foundation (Concrete must cure before building)
Do you need a permit to build your deck? Locally, you can ask the building department.
What are the most valuable features included in decks these days?