European Windows for Custom Homes in Vaughan and King City
Custom houses and country properties need window packages that are large, varied and consistent from the front door to the back terrace. From our Oakville showroom, InterHaus brings Austrian-made Internorm windows and doors, along with Belgian Reynaers and German Schüco aluminum systems, to the team designing and building your house.
The short answer
For custom homes in Vaughan and King City, InterHaus provides Internorm tilt and turn windows, lift & slide doors and entrance doors, plus Reynaers and Schüco systems in all-aluminum, with supply, installation or site supervision. As Internorm’s official Canadian dealer, it works with owners, architects and builders from its Oakville showroom. Vaughan falls in SB-12 climate Zone 1, and King City almost certainly does too.
Big houses, big openings and long winters
A custom home window package is rarely simple. It might include a tall pivot or glazed entrance door, two-storey glazing over a stair or great room, a wide lift & slide door to the terrace and dozens of tilt and turn windows that all have to match in colour, profile and sightline. Ordering that from one supplier, with one set of drawings and one site contact, saves a lot of coordination.
The climate raises the stakes. Ontario’s climate tables give Vaughan (Woodbridge) 4,100 heating degree-days and a −20 °C January design temperature, noticeably colder than Toronto City Hall’s 3,520. A house on an open lot also takes more wind than one on a sheltered street. Triple glazing, three layers of gaskets and concealed multi-point locking are what keep a large window quiet and free of drafts in those conditions.
Internorm gives you one design language across different frame materials. Its uPVC/aluminum and wood/aluminum windows share the same aluminum exterior, so living spaces can have timber interiors while mudrooms, garages and basements use uPVC, and the outside of the house still reads as one.
How we support the design and build team
On a custom home, the window supplier works inside a team and has to fit the architect’s and the builder’s way of working. Our product specialists have architectural backgrounds, so drawings, wall sections, sill and head details are discussed directly with the people who drew them.
Architects and builders can register for our trade portal to download CAD and Revit files, specification sheets and installation guides for Internorm systems. Design offices can also book a PHI accredited Lunch & Learn, at our showroom, at their office or online.
On site, builders pick the arrangement that suits their crew: Supply Only from our Ontario warehouse, Supply & Install by our own fitters, or Supply & Supervision, where our team spends time on site guiding the builder’s installers through handling, fitting and the airtight connection between window and wall. For Passive House projects, we provide a quote within 72 hours.
Systems we specify for estate and country homes
Each opening gets the system that suits it. These are the ones that come up most often on large custom houses.
KF 520 uPVC/Aluminum
I-tec Secure flap locking as standard, available up to security class RC3, with a Uw as low as 0.63. A good fit for ground-floor and less overlooked elevations.
HF 510 Wood/Aluminum
I-tec Core laminated timber keeps the frame stable enough for larger window sizes. Uw as low as 0.65 and 35–47 dB of sound reduction.
HS 330 lift & slide door
Timber inside, aluminum outside, glass up to 3.2 m high and sashes up to 400 kg, with upgrades to RC2 or RC3 available.
Reynaers MasterLine 10 and Schüco AWS 90.SI+
All-aluminum windows with Passive House Institute certified configurations, for slim modern facades and large architectural openings.
Internorm entrance doors compared
The front door is the piece of a custom home people touch most. Internorm’s aluminum entrance doors are thermally broken all around, through frame, panel and threshold, with an Internorm foam insulation core.
| AT 500 | AT 530 | AT 540 | HT 400 | HT 410 | |
|---|---|---|---|---|---|
| Material | Aluminum | Aluminum | Aluminum | Timber/aluminum | Timber/aluminum |
| Uw as low as (W/m²K) | 0.91 | 0.75 | 0.78 | 0.73 | 0.58 |
| Sound reduction | up to 40 dB | up to 34 dB | up to 34 dB | up to 34 dB | up to 34 dB |
| Security | up to RC 3 | up to RC 2 | up to RC 2 | up to RC 2 | up to RC 2 |
| Locking | Multi-point | Multi-point | Multi-point | Multi-point | Multi-point |
Figures from our entrance doors page. The AT 520, also in the range, publishes a Uw as low as 0.81 and up to 32 dB. See every design on the entrance doors page.
Security for larger and more private properties
A big house set back from the road, or a country property with no close neighbours, has more ground-floor glass and fewer eyes on it. Ontario’s building code already sets a forced-entry test, from the NAFS window standard, for any window in a home that sits partly within 2 m of ground level, which takes in basement walkouts and most ground-floor rooms.
Internorm goes further with hardware you cannot see. The I-tec Secure system on the KF 510 and KF 520 uses flaps that press into all four sides of the frame when the window locks, which makes the sash very hard to lever out, and it is available up to European security class RC3. Internorm’s uPVC/aluminum windows are PAS 24 certified. The AT 500 entrance door reaches RC 3, and the HS 330 lift & slide door can be upgraded to RC2 or RC3.
Because the hardware is concealed, none of this changes the look of the window. Security levels can be matched to each elevation during specification, so the ground floor can take the higher class while upper floors stay at standard specification.
Climate zone, the King City question and new-build rules
Ontario’s SB-12 rules use heating degree-days to set the climate zone: under 5,000 is Zone 1, 5,000 or more is Zone 2. Vaughan (Woodbridge) is listed at 4,100, so it is Zone 1. King City is not listed in the province’s SB-1 climate table, but its nearest listed neighbours are all under 5,000: Richmond Hill at 4,000, Aurora at 4,210 and Newmarket at 4,260. King City is therefore almost certainly Zone 1 as well. That is an inference, so confirm it with your designer or the local building department before the energy design is fixed.
For a new custom home, SB-12 sets window performance through prescriptive packages or a modelled performance path, and the code’s stated aim is housing 15% more efficient than under the 2012 code. Those window values come from CSA A440.2 or NFRC testing. European Uw figures follow EN ISO 10077, and research by RDH Building Science showed results for one and the same window shifting by as much as a quarter between the two methods.
If you are building to Passive House, the Passive House Institute’s criteria for its cool-temperate climate zone call for a component Uw of 0.80 or lower and 0.85 or lower once installed. Internorm’s KF 410 carries Passive House Institute certification, and our Passive House windows page covers the certified options. One more point for new builds: the Home Renovation Savings Program does not cover new homes, as it needs at least six months of occupancy. Published price ranges are collected in our guide to European window costs in Ontario.
Where to see our work
Our published projects are elsewhere in Ontario and Québec. The closest comparisons on our projects page are a High Energy Efficient Home in Mulmur, a Passive House residence in Niagara-on-the-Lake, the Etobicoke Passive House Residence in Toronto, a private residence near Kingston and the Devil Lake Cabin. Several are Passive House or high-efficiency homes, the performance class many custom homes now aim for.
To see the products themselves, the Oakville showroom has full-size windows, entrance doors and lift & slide doors you can operate. If you are new to European hardware, our tilt and turn windows guide is a good primer before a visit to the Oakville showroom.
Job-site photos from InterHaus projects
“My preferred window supplier for any of our projects with ambitious sustainability or indoor comfort goals. They have been easy to work with, and responsive when I need a problem solved. Internorm products have served me well, and these are the best, most reliable suppliers I have found in eastern Canada.”
Vaughan and King City questions
Yes. New custom homes are a core part of our work, alongside renovations, and we deliver Internorm, Reynaers and Schüco products to projects across Canada. Every unit is made to measure, so the package follows your drawings rather than a standard size list.
Yes, and on custom homes that is the usual arrangement. Our specialists review drawings and details with your architect, the trade portal provides CAD and Revit files, and builders can choose supply only, supply and install, or supply with on-site supervision.
On published figures, the HT 410 timber/aluminum door, with a Uw as low as 0.58 W/m²K. Among the aluminum doors, the AT 530 is lowest at 0.75. If security comes first, the AT 500 reaches RC 3.
King City is not listed in Ontario’s SB-1 climate table. Nearby listed places, including Vaughan at 4,100 and Aurora at 4,210 heating degree-days, are all under the 5,000 threshold for Zone 2, so King City is almost certainly Zone 1. Confirm it with your designer or the building department.
No. The program covers existing detached, semi-detached, row and townhomes with at least six months of occupancy, and new builds are excluded. It suits a renovation of an existing Vaughan or King City house instead.
Internorm’s I-tec Secure locking, standard on the KF 520, uses flaps that press into all four sides of the frame and is available up to RC3. Combined with the code’s forced-entry rule for windows near ground level, it gives a ground floor solid protection without visible hardware.
Start your Vaughan or King City window package
Send your architectural drawings or window schedule, or meet us at the Oakville showroom with your designer. We will specify each opening and return a line-by-line quote.
Sources
Climate, code and incentive details were checked on November 10, 2026. King City’s climate zone is inferred from nearby listed locations, as explained above.
- SB-1 Climatic and Seismic Data (Table 2) · Government of Ontario, 2024 Building Code Compendium · Vaughan (Woodbridge) 4,100 HDD, −20 °C; Richmond Hill 4,000, Aurora 4,210, Newmarket 4,260 HDD. King City is not listed.
- SB-12 Energy Efficiency for Housing · Government of Ontario, 2024 Building Code Compendium
- Part 9: Housing and Small Buildings (9.7.5.3 forced-entry resistance) · Government of Ontario, 2024 Building Code Compendium
- Home Renovation Savings Program: Additional Program Eligibility Requirements (Nov 2025) · Enbridge Gas and IESO · New builds excluded; at least six months of occupancy required.
- Certification criteria for transparent building components, version 5.2 · Passive House Institute
- Energy Performance of Windows: Navigating North American and European Window Standards · RDH Building Science (CCBST 2014)