# Ontario Window Replacement 2026: ER Ratings, ENERGY STAR and GTA Cost Guide **URL:** \ **Category:** Ontario\ **Created:** [April 26, 2026, 7:06pm UTC](https://home.renovation.reviews/t/ontario-window-replacement-2026-er-ratings-energy-star-and-gta-cost-guide/46909 "2026-04-26T19:06:11Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![system](https://home.renovation.reviews/user_avatar/home.renovation.reviews/system/32/77_2.png) [@system](https://home.renovation.reviews/u/system)\ **Post date:** [April 26, 2026, 7:06pm UTC](https://home.renovation.reviews/t/ontario-window-replacement-2026-er-ratings-energy-star-and-gta-cost-guide/46909/1 "2026-04-26T19:06:11Z")
Canada’s Energy Rating (ER) system rates windows differently from US U-factor. Higher ER = better performance. ENERGY STAR in Ontario requires ER \>= 29. Budget windows often sit at ER 15-20 – functional but costly to operate. **Frame materials:** - Vinyl (uPVC): Most popular in Ontario, good thermal break, mid-range cost - Fiberglass: Best thermal performance, premium price - Wood: Highest aesthetics, requires maintenance - Aluminum: Poor insulation unless thermally broken – avoid for Ontario climate **Double vs triple glazing:** - Double-pane low-E argon: ER 28-35, adequate for most applications - Triple-pane: ER 38-50+, recommended for north exposures, noise reduction, near-net-zero targets **GTA cost ranges (supply and install, 2026):** - Standard double-hung vinyl: $600-$900/window - Casement double-pane: $700-$1,100 - Triple-pane premium: $1,000-$1,800 - Full-house (15-20 windows): $12,000-$25,000 **Greener Homes Grant:** Up to $250/window, max $5,000. ENERGY STAR certification required. Note: installation quality matters as much as product spec. Air leakage around the frame – not through the glass – is the primary heat loss path. _Window contractor reviews at [home.renovation.reviews](https://home.renovation.reviews)_