Parkade Leaks: What Causes Them and How to Plan the Repair

Residents usually notice parkade leaks before anyone else. Someone finds white spots on their car’s paint. Someone else mentions the drip that lands on the same stall every time it rains. Then the council gets photos of white streaks down the ceiling and rust-coloured stains on a wall, and the questions start: how bad is this, where is it coming from, and what will it take to fix?

The good news is that most parkade leaks come from a short list of causes, and many of them can be repaired from below without tearing anything up. In this post we’ll walk through where the water comes from, what to log, which repair options you’ll hear about, and how to plan the work in an occupied building. When you’re ready for a site visit, our parkade crack and leak repair page explains how we work.

Where parkade leaks come from

An underground parkade is a big concrete structure sitting in wet ground, often with landscaping, a plaza or a building on top. Water can reach it from the soil around it and from the surfaces above it. These are the usual sources:

• Cracks in suspended slabs. A suspended slab is a concrete floor or ceiling held up by columns and beams, with open space below. Water from the level above, or from a deck or planter on top, works down through cracks and drips onto the cars underneath.
• Cracks in slab-on-grade. The lowest level usually sits directly on the ground. When groundwater rises, it can push up through cracks in that slab.
• Cold joints and construction joints. Parkades are poured in sections. Where one pour meets another, there’s a seam that never fully bonds, and water follows it.
• Below-grade walls. Perimeter walls hold back wet soil. Shrinkage cracks, tie holes (small holes left by formwork ties) and honeycomb (poorly consolidated concrete full of voids) all let water through.
• Penetrations and drains. Pipes, conduits and floor drains pass through the concrete. The joint around each one is a common leak point.
• Failed waterproofing above. Plaza decks, courtyards and planters over the parkade rely on a waterproofing membrane on top of the slab. When that membrane fails, water gets into the slab and comes out underneath.

What we fix from below, and what’s a deck job

We repair cracks, joints, tie holes, honeycomb and penetrations from the inside of the parkade, using Kryton’s Krystol crystalline waterproofing materials. That covers a large share of parkade leaks, especially in walls, slab-on-grade and individual cracks in suspended slabs.

Replacing a failed membrane on a plaza deck or traffic surface above is a different, top-side job. If the inspection points to a widespread membrane failure, we’ll show you what we found so you and your building’s engineer can plan the right repair. Ask us whether that work suits your building.

Warning signs to log

Before you call anyone, start a simple log. It will make any inspection faster and help your council compare quotes on the same basis.

• Efflorescence. White, crusty or powdery deposits around cracks and joints, often running down the ceiling in streaks. It’s minerals left behind as water moves through the concrete and evaporates.
• Rust staining. Orange or brown streaks can mean water is reaching the reinforcing steel inside the concrete.
• Spalling. Concrete flaking or breaking away from the surface, sometimes exposing steel. This one goes to your engineer first.
• Active drips. Note the stall numbers and grid lines.
• Ponding. Puddles that come back at the base of walls, columns or ramps.

For each one, take a photo and write down the date and the weather. The most useful thing you can record is when it leaks. Does it drip only during or after heavy rain? Hours later? All the time, even in a dry spell? Rain-only leaks point toward water coming from above or from a rising water table after storms. Constant leaks point toward groundwater.

Why it matters

A few drips can seem minor, but parkade leaks rarely fix themselves.

• Rebar corrosion. Water that reaches the steel inside the concrete causes rust. Rust expands, which cracks the concrete further and lets more water in.
• Damage to vehicles and storage. Mineral-laden drips mark paint, and storage lockers along wet walls can damage belongings.
• Slip hazards. Wet, slick patches on drive aisles and walkways are a safety concern for residents and visitors.
• Complaints and confidence. Ongoing leaks are a headache for building managers and wear down residents’ confidence in how the building is being looked after.

Repair options you’ll hear about

When you start getting opinions, you’ll likely hear these four terms. Here’s what each means in plain words.

Crack and joint sealing from below with crystalline materials

The leaking crack or joint is cut out into a clean channel, active water is stopped with a rapid-setting plug, and the channel is packed with crystalline repair material. Crystalline products react with moisture to form crystals inside the concrete, so the repair becomes part of the slab or wall. This is what we do, and it works on the wet or underside face. For more on the method, see our article on crystalline waterproofing explained.

Injection

A material is injected into the crack under pressure to fill it through the depth of the concrete. It’s typically used where a crack is wide, deep or still moving slightly. We use compatible injection where a crack needs it.

Coatings

A product is rolled or sprayed onto a surface. Coatings can protect sound concrete, but painting over an active leak from the underside rarely holds, because water pushes the coating off.

Membrane replacement above

The old waterproofing membrane on top of a deck or plaza is removed and replaced. It’s the right fix when the membrane itself has failed across a wide area, but it’s a bigger project that involves opening up the surface above. A contractor or engineer may recommend it after an inspection; ask us whether it suits your building.

Not every crack needs any of these. Our guide to which concrete cracks need repair explains how to tell.

Planning repairs in an occupied building

Most parkades can’t simply close, so repairs have to fit around residents. Here’s what to plan for:

• Stall closures. Work happens at specific cracks and joints, so usually only the stalls around them need to be empty. Map the affected stalls from your log so owners know in advance.
• Phasing. Larger jobs can be split into zones so part of the parkade is always usable.
• Notices to owners. Give residents clear notice of dates, affected stalls and where to park instead.
• Noise and dust. Cutting out cracks and joints makes some noise and dust. We keep both down as much as we can and clean up as we go.
• Scheduling around rain. Here’s a twist: wet weather is a good time for us. We’d rather seal a leak while water is running, because it shows exactly where the path is. In the Lower Mainland and Fraser Valley the wet season gives us plenty of chances to see a leak in action.

For strata councils and property managers: getting a useful quote

A good quote starts with good information. Before the site visit, pull together:

• Your leak log with photos, stall numbers, dates and weather.
• Any relevant reports, such as a depreciation report or engineer’s report that mentions the parkade.
• Building drawings, if you have them, showing slab levels, decks and planters above.
• The building’s age and any history of past repairs.
• Access details: gate codes, the best times to work and who the contact is on site.

Our quote comes from a site look, not a phone guess. We’ll walk the parkade, look at each leak and give you a clear plan in plain terms you can take back to council. If the parkade is one of several issues, our strata and building deficiency repairs page covers patio, foundation and retaining wall leaks too.

Common questions

Can parkade leaks be fixed from underneath without tearing up the deck above?

In many cases, yes. Leaking cracks, joints, tie holes and penetrations can be repaired from the underside using crystalline materials that work against water pressure. If the source is a widespread failure of the membrane on the deck above, though, that calls for a top-side membrane repair instead. We’ll tell you which situation you’re in after we look.

What are the white streaks on our parkade ceiling?

That’s efflorescence: minerals carried out of the concrete by water and left behind when it evaporates. It tells you water has been moving through that crack or joint, even if it’s dry the day you look. It isn’t harmful in itself, but it shows where to look, so photograph it and note where it is.

Do we need to close the whole parkade for repairs?

Usually not. Crack and joint repairs happen at specific locations, so normally only the stalls around the work need to be cleared. Bigger jobs can be phased by zone. We’ll plan the sequence with your property manager so owners get clear notice of which stalls are affected and when.

Is every crack in a parkade a problem?

No. Concrete shrinks as it cures, and fine dry cracks are common and often harmless. The ones that need attention are cracks that leak, show efflorescence or rust staining, keep widening, or have one side offset from the other. Wide, moving or offset cracks and any spalling should go to your building’s engineer first.

Can you fix leaks around pipes and floor drains?

Yes. Where pipes, conduits and drains pass through the concrete, the joint around them often wasn’t sealed well when the building went up. Those penetrations are a common source of drips in parkades. We cut out and pack the joint around the penetration with crystalline repair materials, the same way we treat a leaking crack.

Book a free parkade inspection

If your parkade leaks every time it rains, start a log this week and then give us a call. We repair parkade leaks for strata councils, property managers and building owners across Vancouver, Burnaby, Richmond, Surrey and the Fraser Valley. Read more about our parkade crack and leak repair, then call (778) 686-2221 (Mon–Sat, 8:30 AM–5:00 PM) or request your free inspection.