Deck blocks are pre-cast concrete supports that sit on a compacted gravel base and carry a floating, non-attached deck. They are the most cost-effective deck foundation in Ottawa, install in hours with zero digging, and come standard on every Luxury Decking Silver and Gold package, starting at $3,995 plus HST for a 12x12.
Because a deck on blocks is structurally independent of your house, it moves with the ground instead of fighting it. That makes deck blocks the right choice for low, free-standing platforms and garden decks, and the wrong choice for anything attached to your home. This guide covers when they work, when to upgrade, and what a floating deck actually costs in Ottawa.
A deck block foundation is a series of pre-cast concrete blocks, each set and levelled on a 4 to 6 inch base of 3/4 inch clear crushed stone. The deck frame sits in moulded slots on top of the blocks. There is no excavation, no concrete curing time, and no heavy machinery, so a full base can be set and levelled in hours and framing can begin the same day.
Zero digging also means zero risk to underground utilities. For yards with gas, water, or electrical lines running through them, a surface-supported foundation is the safest option available. Your landscape stays undisturbed, with no dirt piles left on the lawn.
Deck blocks are the right choice for low, free-standing decks that are not structurally tied to your home. The classic use cases are ground-level platforms, garden decks, and budget-conscious builds where eliminating excavation keeps labour and material costs down. Low free-standing platforms of this kind typically do not require a full structural permit, which keeps the project simple.
They are also the fastest foundation we install. Because there is no curing time, a Silver or Gold package on deck blocks moves from foundation to framing in a single day. That speed, plus the eliminated excavation cost, is why deck blocks are the standard foundation on our two most popular package tiers.
Deck blocks sit on the surface, so they are subject to ground movement. Ottawa winters push frost deep into the ground and put every yard through 60 or more freeze-thaw cycles a year, which means a deck on blocks will rise and fall slightly with the seasons. Because the deck is free-standing, this seasonal movement does not harm the structure.
The hard limit: never attach a deck on blocks to your house. Building code prohibits attaching a surface-supported floating deck to a frost-protected structure. If the ground moves and the house does not, the movement can rip the ledger board off your home and cause serious damage. Any deck that attaches to the house, sits high off the ground, or carries a hot tub needs a frost-protected foundation such as dug cement footings or helical piles.
Deck blocks are the included foundation on Silver and Gold packages, so the package price is the foundation price. Silver packages (premium pressure-treated wood on a 2x8 PT frame at 16 inches on centre): 12x12 $3,995, 12x16 $5,895, 12x20 $6,995, 16x16 $7,495, 16x20 $9,495, 20x20 $11,795. Gold packages (premium composite from Fiberon GoodLife, TimberTech Prime, or Eva-Last Infinity on the same floating foundation, with 25 to 30 year material warranties and 8 colour options): 12x12 $7,495, 12x16 $9,995, 12x20 $11,995, 16x16 $12,995, 16x20 $15,995, 20x20 $19,895.
All prices are plus HST, quoted without railings, and every build carries our 5-year labour warranty. These are the same published packages shown on our pricing page. For a full cost breakdown across all four tiers, see the Ottawa Deck Cost 2026 guide, and for custom dimensions the InstaQuote calculator prices your exact size in about 30 seconds.
Deck blocks are the surface option: fastest, least expensive, free-standing only. Dug cement footings are the traditional frost-protected option for attached and heavier decks, available as a $1,049 upgrade on Silver and Gold packages and included standard on Platinum. Helical piles are the engineered steel option with zero excavation and immediate load capacity, available as a $1,440 upgrade on Silver and Gold and included standard on Diamond packages.
Every foundation we install passes through our Digital Quality Verification system, which requires photo sign-off of the base preparation and levelling before the deck frame is finalized. For a side-by-side breakdown of all three systems, see the foundation comparison page.
What is a deck block foundation? A deck block foundation uses pre-cast concrete blocks set on a compacted gravel base to support a floating, non-attached deck. The deck frame sits in slots on top of the blocks, so there is no digging, no concrete curing, and no disturbance to your yard. It is the standard foundation on Luxury Decking Silver and Gold packages.
Can I attach a deck on blocks to my house in Ottawa? No. Building code prohibits attaching a surface-supported floating deck to a frost-protected structure such as your house. If the ground moves and the house does not, the movement can rip the ledger board off your home and cause serious damage. Decks on blocks must remain free-standing.
Do I need a gravel pad under deck blocks? Yes. For long-term stability we recommend a 4 to 6 inch base of 3/4 inch clear crushed stone under every block. The gravel provides essential drainage and prevents the blocks from sinking into soft topsoil over time.
Will a deck on blocks move in Ottawa winters? Slightly, yes. Deck blocks sit on the surface, so the deck rises and falls a little with seasonal ground movement through Ottawa's 60 or more freeze-thaw cycles each year. Because the deck is free-standing and structurally independent of the house, this seasonal movement does not damage the structure.
How much does a floating deck on deck blocks cost in Ottawa? Silver packages on deck block foundations start at $3,995 plus HST for a 12x12 in premium pressure-treated wood and run to $11,795 for a 20x20. Gold packages in premium composite on the same foundation run from $7,495 (12x12) to $19,895 (20x20). All prices are without railings and include a 5-year labour warranty.
When should I upgrade from deck blocks to footings or helical piles? Upgrade when the deck will attach to the house, sit higher off the ground, or carry heavy loads such as a hot tub. On Silver and Gold packages, dug cement footings add $1,049 and helical piles add $1,440. Platinum packages include cement footings and Diamond packages include helical piles as standard.
Run your dimensions through the InstaQuote calculator for an instant price across all tiers, deck blocks included. Book a mobile showroom visit and we bring board and colour samples to your driveway. Or book a free on-site assessment and our team will confirm whether deck blocks or a frost-protected foundation is right for your yard, with a written quote to follow. Call 613 707-3060 or email info@luxurydecking.ca.
Explore more: InstaQuote Calculator | Deck Pricing | Ottawa Deck Cost 2026 | Compare All Foundations | Concrete Footings | Helical Piles