Heaving posts
One post sits higher every spring, or a pier pokes further out of the ground than it used to. That is frost lifting the footing.
Deck Repair & Re-Footing · Hamilton
Sinking deck repair and re-levelling in Hamilton
Posts heaving, boards sloping, a gap opening up where the deck meets the house? Postech Hamilton re-supports existing decks on engineered screw piles set below the frost line, so in many cases the deck you already have can be levelled and kept instead of torn down.
Existing decks re-supportedOften without a teardown
Piles below the frost lineSteel, not short sonotubes
Start with a photoFree quote for Hamilton decks
Signs of a failing footing
Is the deck moving, or just old?
Most deck problems in Hamilton start underneath, at the footings. When a concrete pier lifts in winter or sinks into soft ground, the post on top of it moves with it, and everything the post carries goes out of level. Boards, railings and stairs are usually the last things to show it.
Walk the deck and look underneath. If you see any of the signs below, the footings are the first thing to check. A deck that moves a little more each winter will not settle back on its own, and it is far cheaper to re-support the frame early than to replace rotted or cracked framing later.
Sinking or sagging decksFrost-heaved posts and piersDecks pulling away from the houseCracked or tilting concrete footingsBouncy or uneven deck floorsStairs and landings that have dropped
Sloping boards
Water pools in one corner, a ball rolls to one side, or the deck dips toward the yard. A footing has settled or lifted.
Gaps at the ledger
A gap opens where the deck meets the house, or the ledger board looks twisted. The outer posts are pulling the frame away.
Railings out of plumb
Guards lean, wobble or no longer line up. Railings follow the frame, so a leaning railing often points to a moving post.
Stairs pulling away
The top step no longer meets the deck cleanly, or the stringers have dropped at the landing.
Doors that rub
A patio door scrapes the deck surface or the threshold sits higher than the boards. The deck has moved relative to the house.
Hamilton frost and clay
Why sonotube footings move here.
Much of Hamilton, on the Mountain and below the escarpment, sits on clay and silty soils that hold water. When that wet soil freezes, ice forms in layers and the ground swells upward. Frost can also grip the sides of a concrete sonotube and lift it, even when the bottom is deep enough. In spring the thawed clay is soft and wet, and a footing that was lifted can drop back unevenly or keep sinking.
The Ontario Building Code calls for footings to bear below frost depth, which in the Hamilton area is commonly taken as about 1.2 m (4 ft). Many older decks were built on shallow tubes, deck blocks or piers poured on loose backfill next to the house, and those are the decks we see moving. A footing can also fail because the concrete was poured without a wider base, so there is nothing to stop it rising.
A screw pile works differently. The steel shaft is turned down through the frost-affected soil to firmer ground, and the helical plates at the bottom anchor it there, resisting both settlement and uplift. There is no concrete for frost to grip at the surface. For a closer look, read our guide to screw piles vs. sonotubes.
How the repair works
New piles beside or under the deck you already have.
The deck stays where it is while we work. Piles are installed with compact equipment that fits through a side gate and works close to the existing frame.
Assess from photos
Your photos show us the deck height, the post and beam layout and the worst footing. We confirm what we can on site before quoting the work.
Support the frame
The beam is temporarily shored so the load comes off the failing posts and footings.
Install the piles
New screw piles go in beside the old footings or directly under the beam line, and the installation torque of each pile is recorded.
Level and connect
The frame is brought back to level and fastened to the new pile caps. The old footings are cut down or left below grade.
Re-level or rebuild
Keep the deck, or start again?
The footings are often the only part that has failed. When the frame is sound, re-supporting it is quicker and costs far less than a new deck. When the frame is rotted, a rebuild on new piles is the better money.
Re-level on new piles
- Joists, beams and ledger are solid
- Movement is at the footings, not in the wood
- Boards and railings stay in place
- A few boards may come up for access on low decks
- The deck is back in use soon after the work
Rebuild on new piles
- Framing is rotted, split or undersized
- The ledger is failing at the house
- You want a bigger, higher or covered deck
- Boards and railings are at the end of their life
- See our deck construction service
| Part of the deck | Re-level on new piles | Full rebuild |
|---|---|---|
| Footings and posts | New screw piles; failed posts replaced where needed | New screw piles under a new frame |
| Beams and joists | Kept, brought back to level | Replaced |
| Deck boards | Kept; a few may be lifted for access and reinstalled | Replaced |
| Railings and guards | Kept and re-plumbed with the frame | Replaced, under a building permit |
| Stairs and landing | Re-supported on their own pile where needed | Rebuilt with the deck |
Permits for deck repair
When the City of Hamilton needs a permit.
The City of Hamilton requires a building permit for any deck or porch attached to the house, whatever its size, and for larger or higher detached decks. Replacing or installing new guards (railings) also needs a permit. Permit drawings for a deck include the footing or pier details, so new footings under a permitted deck are part of that review.
Simple re-levelling and footing work may not need a new permit in every case, but it is the owner's job to confirm before work starts. Call the City's Building Division at 905-546-2720 if you are unsure. We provide the pile installation records for your permit file, and we can tell you what we see on site that the City will ask about.
Planning a new deck instead? Our deck footings page covers foundation-only work for new builds, and our screw piles vs. concrete footings guide compares the two systems for a new deck.
Deck repair and footing replacementRe-levelling existing decks on screw pilesReinforcing old footings for a deck remodelStair and landing re-supportInstallation records for the permit fileHamilton and surrounding communities
Frequently asked questions
Can you fix a sinking deck without tearing it down?+
Often, yes. If the joists, beams and ledger are sound, new screw piles can be installed beside or under the existing beam line and the deck brought back to level. If the framing is rotted or undersized, rebuilding on new piles is usually the better option.
Why did my deck footings heave?+
Hamilton's clay soils hold water, and when they freeze they swell and can grip the sides of a concrete sonotube. Footings that are too shallow, poured on loose backfill or built without a wider base are the ones that lift. Screw piles extend through the frost-affected soil and their helical plates resist uplift.
Do I need a permit to repair deck footings in Hamilton?+
It depends on the deck and the work. Any deck attached to the house needs a permit to build, and replacing railings needs one too. Check with the City of Hamilton Building Division at 905-546-2720 before work starts. We provide installation records for the permit file.
Can you fix just one post or one corner?+
Yes. If only one or two footings have moved, we can install piles at those posts. We will tell you if the other footings look like they are next, so you can decide whether to do them at the same time.
How much does deck repair on screw piles cost?+
Cost depends on how many piles are needed, the deck height and access, the soil, and whether any posts or framing need replacing. Send us photos of the deck and the worst footing for a free quote.
Explore more
More on decks and foundations.
Free deck repair quote
Send us a photo of your deck
Fill in the form with your address and what you are seeing, then email two or three photos to [email protected]: the whole deck, the worst post or footing, and where the deck meets the house. Grant & Kairi West will get back to you about next steps.
Deck repair inquiry