A well-placed skylight or roof window can transform a dark hallway, stair, attic, or kitchen into a bright and inviting space. In Toronto’s climate, you want more than light. You want energy performance, weatherproof detailing, and smart controls that keep heat and moisture in balance year-round. This guide covers what to choose, how to install it properly, and realistic 2025 budgets so you can plan with confidence.

Skylight vs roof window vs sun tunnel

• Fixed skylight: non-operable for pure daylight. Fewer moving parts and excellent for areas that do not need ventilation.
• Vented skylight: operable by manual crank or electric motor to release heat and humidity. Great for kitchens, baths, and top-floor living areas.
• Roof window: in reach, side-hinged or top-hinged units that open wide and can serve as roof access in some cases. Common in finished attics with sloped ceilings.
• Sun tunnel (tubular skylight): a compact reflective tube that brings light to tight spaces like hallways or closets with minimal framing changes.

Picking the right location and size

Daylight works best when balanced with wall windows. Avoid glare by sizing to the room and placing the opening where light will bounce instead of hitting screens directly.

• Stairs and halls: small fixed units or sun tunnels to safely brighten circulation spaces.
• Kitchens: vented units above the prep or island area to exhaust heat and cooking moisture.
• Bathrooms: vented units paired with a proper exhaust fan to reduce fogging.
• Attics and lofts: roof windows for natural ventilation and egress where applicable.
• Bedrooms: add room-darkening blinds for sleep control.

Energy performance that works in Toronto

Look for insulated glass with Low E coatings and warm edge spacers. Curb-mounted units on flat roofs should include a continuous insulated curb and air seal to prevent condensation. In heating seasons, vented skylights can be set to a winter mode to reduce unintended heat loss.

• Glazing: choose double or triple-glazed units with argon-filled cavities. Laminated inner panes add safety and noise reduction.
• Thermal breaks: frames with built-in thermal breaks prevent interior sweating.
• Shades: cellular or blackout blinds improve comfort and cut summer gain.
• Controls: rain sensors auto-close vented units during storms. Smart controls can tie into a thermostat schedule.

Flat roof vs pitched roof details

• Pitched roofs: deck-mounted or curb-mounted units with step flashing and counter flashing integrated into shingles or metal roofing. Maintain proper underlayment laps and ice shield around the opening.
• Flat roofs: always use a well-built curb, fully adhered membrane flashing, and metal counter flashing. Tie into the roof system per the manufacturer’s details and add tapered insulation to shed water away from the curb.

Condensation and moisture control

Toronto winters are dry and cold outside, but humid inside. Moist indoor air can condense on cold surfaces around skylights if detailing is weak.

• Maintain a continuous interior air barrier and seal the drywall return to the frame.
• Insulate the shaft with high R mineral wool or spray foam so the interior surface stays warm.
• Pair vented skylights with a right-sized exhaust fan in bathrooms and kitchens.
• Keep blinds slightly open in winter to allow warm air to wash the glass when needed.

Permits and approvals in Toronto

Most skylight replacements like-for-like do not require a Building Permit. New openings, structural changes to rafters or trusses, or adding a roof window that can serve as egress will require permit drawings. Heritage Conservation Districts and front-facing changes may require heritage review. Flat roof penetrations on rowhouses should consider fire spread and party wall setbacks.

Installation sequence

1. Layout and verify the structure of the attic.
2. Cut opening, install headers, and build curb if required.
3. Set unit, flash, and counter flash per the roof system.
4. Insulate and air seal the shaft.
5. Drywall returns, paint, and install blinds or shades.
6. Commission controls and tests for leaks with a controlled spray or rain event.

Ballpark budgets for Toronto in 2025

Actual costs depend on access, roof type, shaft depth, and controls. These ranges help with planning.

• Sun tunnel installed through shingle roof with basic trim: $1,200 to $2,200
• Fixed skylight replacement, same size on shingle roof with new flashing kit and interior touch-ups: $2,000 to $3,800
• New fixed skylight including framing, shaft, drywall, and paint: $3,500 to $6,500
• Vented skylight with rain sensor and blind full install with wiring: $5,500 to $9,500
• Roof window in finished attic structural framing, drywall returns, trim: $6,500 to $11,000
• Flat roof curb-mounted skylight membrane tie-in and tapered insulation: $4,500 to $9,000

Timeline expectations

A straight replacement can be done in 1 day with interior finishing on day 2. New openings or roof windows typically take 2 to 4 working days, including shaft finishing and paint. Flat roof curb builds and complex wiring can extend the schedule.

Common mistakes to avoid

• Skipping the ice and water shield around the opening in favor of felt only.
• Under-insulating the shaft so that condensation forms in winter.
• Using generic flashing kits that do not match the roofing profile.
• Placing a skylight low in a valley where water pools.
• Forgetting blinds, which leads to heat gain and glare in summer.

FAQs

Will a skylight make my house overheat?
Choose Low E glazing and add a blind. Place the opening to bounce light, not beam it directly on seating or screens. Vented units can purge hot air on summer evenings.

Do skylights always leak?
No. Leaks come from poor detailing. Proper curb construction, manufacturer-specific flashing, and an airtight interior finish keep water out for the long term.

Can I add a skylight to a truss roof?
Sometimes with engineering and a framed box between trusses. It is simpler with site-built rafters. We will verify feasibility during site review.

Ready to bring natural light into your home?

We plan and install skylights that look great and stay dry. From framing to flashing and smart controls, we handle everything. Contact us today to book a consultation.

📞 Call us at: 437-259-9632

✉️ Email us at: jgcontractingyyz@gmail.com

🌐 Website: https://jgcontractingyyz.com