Both are solid options, but they perform differently in BC's climate. We break down cost, durability, look, and maintenance so you can make the right call.
If you're building a new patio or replacing a cracked old slab, the two most common choices are poured concrete and flagstone. Both work well in the Fraser Valley — but they're different products that suit different situations and different homeowners. Here's a straight comparison.
Cost
Concrete is almost always less expensive per square foot than flagstone. You're paying for material that gets poured, screeded, and finished — fairly straightforward labour. Flagstone costs more on material and labour because each stone is individual, irregular in thickness, and has to be fitted, levelled, and set by hand.
The cost gap narrows for smaller patios where setup costs for concrete are proportionally higher. For large areas — 200+ square feet — concrete typically has a clear cost advantage on the initial build.
Appearance
This is where flagstone wins clearly. A well-installed flagstone patio has a natural, hand-crafted look that plain concrete can't replicate. Natural stone textures, colour variation, and the way the joints look filled with either mortar or polymeric sand give flagstone a warmth and character that stamped or coloured concrete only approximates.
Concrete has improved — exposed aggregate, salt finishes, and stamped patterns look genuinely good — but it still reads as concrete. Flagstone reads as stone.
Durability in BC's Climate
Both hold up well, but in different ways and with different failure modes.
Concrete is strong in compression but doesn't handle differential movement well. Ground shifts, frost heave, and tree roots cause cracking — and cracked concrete slabs are common in Chilliwack's clay-heavy soils. Once a concrete slab cracks, the repair options are limited. You patch it (visible), grind it (limited), or replace it.
Flagstone handles movement better. Because each stone is independent, one stone can shift without cracking the ones around it. The trade-off: individual stones on a dry-set installation (sand base) can settle unevenly over time, creating trip hazards. This is a maintenance issue, not a failure — settled stones can be re-levelled. Mortar-set flagstone is more stable but less forgiving of movement.
Maintenance
Concrete: seal every 2–3 years if you want it to look good and resist staining. Cracks should be filled as they appear to prevent water ingress. Power washing keeps it clean.
Flagstone: mortar joints in a mortar-set installation need repointing every 15–25 years. Polymeric sand in a dry-set installation should be refreshed every few years as it erodes. Individual stones can be re-set if they shift. A penetrating sealer extends the life of softer stones like sandstone.
Neither is particularly high maintenance, but flagstone's maintenance is more targeted — you fix the spots that need it rather than treating the whole surface.
Which Should You Choose?
Choose concrete if: you need a large area at lower cost, you want a perfectly flat and consistent surface, or you're doing a driveway extension alongside the patio.
Choose flagstone if: appearance matters to you, you want something that complements a garden or natural landscape, the area is smaller, or you're building an outdoor living space where the patio is a feature, not just a surface.
We install both — flagstone masonry is our speciality, but we work alongside concrete contractors on projects that need both. If you're not sure what's right for your Chilliwack property, give us a call and we'll give you an honest recommendation based on the site.