How much does it cost to have a Calgary contractor stain and seal a 300 square foot deck?

Professional deck staining and sealing in Calgary typically costs $900-$2,400 for a 300-square-foot deck, or $3-8 per square foot depending on the deck's condition and the quality of products used.

The wide price range reflects several factors that significantly impact the scope of work. A deck in good condition that just needs cleaning and a fresh coat of stain will be at the lower end ($3-4 per square foot). However, if your deck has weathered grey wood, peeling stain, or mildew staining, the contractor will need to strip the old finish, sand the surface, and possibly replace damaged boards before applying new stain — pushing costs toward $6-8 per square foot.

Calgary's extreme climate makes proper surface preparation especially important. The city's intense UV at 1,045 metres elevation and chinook freeze-thaw cycling are hard on deck finishes. Many contractors will power wash the deck, apply a deck brightener or cleaner to remove grey weathering, lightly sand high-traffic areas, and then apply a UV-blocking stain designed for extreme weather conditions. Quality exterior stains rated for Alberta's climate (like Sikkens, Cabot, or Benjamin Moore Arborcoat) cost more than basic stains but last 3-4 years instead of 1-2 years.

The timing of staining work affects both cost and quality. Calgary's short outdoor season means most deck contractors are fully booked for staining from May through September when temperatures consistently stay above 10 degrees Celsius. Booking early in the season or late (September) sometimes offers better rates. The stain needs 24-48 hours of dry weather to cure properly, so contractors often charge a premium for guaranteed scheduling during Calgary's unpredictable spring and fall weather.

Additional costs to consider include: deck repairs discovered during cleaning ($8-15 per square foot for board replacement), upgrading to premium semi-transparent or solid stains that better hide wear patterns, and applying deck sealer to high-traffic areas like stairs and railings. Some contractors include basic repairs in their staining quote, while others charge separately.

DIY staining costs $150-450 in materials for the same 300-square-foot deck — about $0.50-$1.50 per square foot for cleaning products, stain, and brushes or rollers. However, professional application ensures proper surface preparation, even coverage, and warranty protection. Many Calgary homeowners find the time investment (2-3 full days including prep work) and physical demands of deck staining make professional service worthwhile.

When to hire a pro: Always use professionals for elevated decks where safety is a concern, decks requiring extensive stripping or sanding, or when you want warranty protection on the finish work. Calgary Deck Contractors can match you with experienced staining professionals who understand how Alberta's climate affects deck finishes and use products rated for extreme weather cycling.

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Looking for experienced contractors? The Calgary Construction Network connects homeowners with qualified professionals:

• WestAim Construction Ltd.
• Quality count construction Ltd.
• Durable Decks
• Makki Abatement
• Radon Lab