Pavers Sloping Toward the House? Fix the Grade Before It Floods the Basement
Pavers that slope toward the house need to be lifted and re-levelled so the surface falls away from the foundation again, and the reason they settled, almost always water in the base, needs to be fixed at the same time. Left alone, every rain runs to the wall, down the foundation and into the basement.
This is one of the most common calls we get for patio and interlock restoration in Hamilton, and one of the few that should not wait a season. Here is how to tell if you have it, why it happens, and what the fix involves, including the yard drainage work that usually goes with it.
How to tell which way your patio drains
Wait for a steady rain, or run a hose on the patio for ten minutes, and watch where the water goes. If it runs to the house wall, pools along the foundation, or sits against the step at the door, the patio is draining the wrong way. On a dry day, lay a long straight board across the pavers from the wall outward and set a level on it: the bubble should show the far end lower than the wall end. A damp line on the basement wall below the patio, or a musty smell after rain, is the same problem seen from inside.
Why it happens in Hamilton
Patios are built to fall away from the house. They end up falling toward it for a few reasons, and we see all of them in Hamilton:
- The soil along the foundation settles. Backfill against a house keeps compacting for years after it is built, especially on the clay of the Mountain and the newer subdivisions. The pavers nearest the wall sink with it, and the patio now tilts inward.
- A downspout empties onto or beside the patio. The water washes the fines out of the base in that corner, the corner drops, and the slope reverses.
- Frost. Water that sits in the base under the house side freezes and heaves the pavers, then drops them lower than they started when it thaws. A few winters of that and the fall is gone.
- It was never right. A patio laid level, or with too little fall, needs only a small settlement to tip the wrong way.
Why it matters more than a cosmetic dip
A foundation is not meant to be the low point of the yard. Water against the wall finds its way through the joint at the footing, through a crack, or through the window well. The basement gets damp, then wet. Over years, water sitting against a foundation in freeze and thaw does real damage to the wall. The fix outside is far cheaper than the fix inside, which is why this is the one patio repair we tell people not to put off.
How we fix it
- Find the water. Before anything is lifted we look at where the downspouts empty, where the neighbour’s yard drains, and where the water sits. If a downspout is the cause, it gets an extension or an underground run away from the house first.
- Lift the pavers on the settled side and set them aside in order, so the pattern goes back the same way.
- Dig out the soft, washed-out base. Bring in new granular, compact it in layers, and grade it to fall away from the wall, usually about a quarter inch per foot.
- Reset the pavers on a fresh bedding layer, flush and level across the joint with the untouched area.
- Restore the edge restraint, sweep in polymeric sand, compact and top up, and seal if you want it sealed.
- Where the yard beyond the patio also slopes toward the house, regrade it or add a swale or a catch basin so the water the patio sheds has somewhere to go. Our page on water draining toward the house covers that side of the job.
In most cases only the settled strip along the house needs lifting, and the patio looks untouched when the work is done. When the whole patio has lost its fall, the whole patio comes up and goes back on a new base. We tell you which on the first visit, and for this problem we do prefer to see the patio and the yard rather than quote from photos, because the fix depends on where the water is coming from.
What not to do
Do not sweep more sand into the joints and hope. Do not pour a concrete fillet along the wall; it cracks and the water finds the crack. Do not pile soil against the foundation to raise the low side; it holds water against the wall and rots the siding. The pavers have to come up so the base can be fixed, and the water has to be sent somewhere else.
Frequently asked questions
Can you fix just the strip along the house?
Usually, yes. If the rest of the patio still falls the right way, only the settled area is lifted and re-based. The whole patio is cleaned and re-sanded afterward so the repair does not show.
Why does my downspout keep sinking the patio?
Because it dumps a roof’s worth of water into one corner of the base every time it rains. Extending it past the patio, or running it underground to a dry well or the lawn, stops the washing out for good. See downspouts, eavestroughs and sinking driveways.
Is this covered by your warranty if you built the patio?
Our work carries a 1-year craftsmanship warranty. Settling caused by how we built the base is on us; a downspout moved after the fact, or a neighbour’s new grading, is a new job, and we will say which it is honestly.
Get it fixed before the next rain
Call (905) 906-0671 or send the form on our contact page with a photo of the patio and the downspouts. We are quick to quote, quick to start, and we answer every call.
