Yard drainage in Calgary guide: check your grading, place downspout extensions right, spot foundation warning signs and handle Chinook melt and winter ice.
Every roof collects a surprising amount of water. A modest bungalow roof sheds hundreds of litres in a single summer thunderstorm, and all of it funnels into a handful of downspouts. Where that water lands in the first metre or two away from the house decides whether it soaks harmlessly into the lawn or works its way down the foundation wall toward the basement.
The ground side of the system gets far less attention than the gutters, even though that is where many basement moisture problems start. This guide covers the yard drainage checks you can do yourself: how the soil around the house should slope, what downspouts should do with the water, the warning signs of poor grading, and what changes through our freeze-thaw winters.
Raico Roofing does not do landscaping or regrading. We install and repair aluminum gutters and downspouts, and drainage problems often show up at ground level during an exterior walk-around. The goal here is to help you spot those problems early and know who to call for each part.
A working drainage path has three stages. The gutter collects water along the eave. The downspout carries it to ground level. Then the ground itself, or an extension, moves it away from the foundation and lets it spread out or soak in somewhere harmless.
The third stage is where things quietly fail. A downspout that empties straight onto soil beside the wall concentrates a whole roof section's runoff in one spot, every storm. Over a few seasons that spot erodes, settles and starts sloping back toward the house.
Soil next to a foundation should fall away from the house, not toward it. Building and landscaping guides commonly describe a noticeable drop over the first few metres, but the exact figure that applies to your property depends on your lot, its approved grading plan and local requirements. Rather than chase a number, start with a simple test: after a rain, does water move away from the walls or sit against them?
Poor grading rarely announces itself with a flood. It shows up as small, repeated clues, often in the same corner of the house. Look for:
Two more are especially common in Calgary. Window wells that fill with water or ice after a storm usually mean surface water is draining into them instead of away. And in winter, a sheet of ice across a walkway or driveway right below a downspout is a sign that water is being released where it can freeze and refreeze on every Chinook cycle, which is both a drainage problem and a slip hazard.
Older homes in established neighbourhoods have one more risk: backfill settlement. The soil placed against the foundation when the house was built tends to settle over the years, sometimes leaving a shallow trench right where the slope should be steepest. Many houses built decades ago have never had that settlement corrected.
Common mistake: building a raised garden bed or piling landscape rock tight against the foundation. Beds that trap soil above grade, or edging that holds water against the wall, can undo good grading and keep siding and its weather-resistive layer wet. Keep soil below the bottom edge of the siding and let the surface slope away.
You can do this on any dry afternoon, then repeat the key steps during or right after a steady rain, when problems are easiest to see.
Some drainage problems are a weekend job. Others need equipment, a site plan, or a trade you should not try to stand in for. This table sorts the common ones.
| Problem | Quick fix | When to call a pro |
|---|---|---|
| Downspout dumps at the wall | Add an extension or splash pad | Downspout is in the wrong spot or undersized |
| Small low spot near foundation | Add and compact soil, slope away | Settlement runs along a whole wall |
| Gutter overflows above wet area | Clean gutter and downspout | Overflow continues when clean |
| Window well fills with water | Clear debris, add a cover | Water enters the basement |
| Ice sheet below downspout | Redirect the outlet off walkways | Ice dams or leaks at the eave above |
| Patio slopes toward house | Seal the joint at the wall | Slab needs lifting or replacing |
If the trouble starts at the roof edge, with overflowing gutters, missing downspouts or water pouring behind the gutter, that is our side of the job. A roofing contractor who handles gutters can tell you whether the system is undersized for the roof area or simply needs repairs and better outlet placement. You can request an exterior inspection and we will look at the gutters, downspouts and the roof edge above them.
Extensions are the cheapest and most effective drainage upgrade most homes can make. The idea is simple: release roof water far enough from the foundation that it soaks in or flows away before it can follow the wall down.
Where the water ends up matters as much as how far it travels. Directing a downspout toward a neighbour's yard or across a public sidewalk can create problems for others and may run against local rules. Check the City of Calgary's current guidance on lot drainage and where roof water and sump discharge can go before redirecting anything toward a property line.
Sometimes the real fix is moving or adding a downspout. A long eave with a single outlet at one corner can push a lot of water to one spot. Adding a second downspout, or relocating one away from a walkway or window well, is a straightforward change when new seamless aluminum gutters are installed, and often possible on existing systems too. Our guide to aluminum gutter installation explains how sizing and outlet placement are planned. On flat Calgary lots, outlet placement often matters more than extension length, because there is little natural slope to carry water away.
If your home has a sump pump, its discharge line is part of the same picture. A sump that empties next to the foundation can recirculate the same water back to the weeping tile. The discharge point should be well away from the house and not create ice hazards in winter. Rules on where sump water can go are set locally, so confirm current City of Calgary requirements before changing it.
Calgary weather adds a twist most drainage guides skip. A Chinook can push temperatures well above freezing in an afternoon, melt the snow on a south-facing roof, and then refreeze everything overnight. That cycle can repeat several times in a single winter.
Ice at the base of a downspout can also be a symptom of a problem higher up. Meltwater running constantly through the gutter on a cold day can point to heat loss and ice building at the eave. Our seasonal roof maintenance guide covers what to check up top before and after winter.
Good drainage is a chain: a clean, properly sized gutter, enough downspouts in the right places, outlets that release water away from the house, and ground that keeps sloping away. If gutter cleaning is on your list, see how to maintain your gutters and downspouts, and for the wall side of water management, our article on moisture control behind siding.
For grading and landscaping work, a landscaper or drainage specialist is the right call. For the roof edge, gutters and downspouts, Raico can help. Contact us for a free exterior inspection, or read more about our soffit, fascia and gutter work and repair and maintenance services.
Far enough that water soaks in or flows away rather than running back to the wall. The right distance depends on your lot slope and soil, so watch where the water actually goes during a rain and extend or redirect the outlet if it returns toward the foundation.
Small low spots can often be filled with compacted soil that slopes away from the house, keeping it below the bottom edge of the siding. Settlement along a whole wall, or water entering the basement, is a job for a landscaper or drainage specialist.
Landscapers commonly use a denser fill or clay-rich soil for the slope next to the foundation, since loose material lets water soak straight down. Ask a landscaping professional what suits your soil before regrading.
No. Raico installs and repairs aluminum gutters, downspouts, soffit and fascia. We can fix the roof-edge side of a drainage problem and point you toward a landscaper for regrading.
Contact Raico Roofing for a free quote.