Cortizo 4700 Sliding Patio Doors: A Review

The Cortizo 4700 Sliding Patio door is one of the aluminium sliding systems we fabricate and install most often across West London, usually specified where a homeowner wants a wide, uninterrupted opening onto a garden or terrace without the panel stack of a bifold. This review sets out what the system actually delivers on a typical UK project.

What the 4700 Is Built For

The 4700 Sliding Patio is Cortizo's standard sliding door platform, available as an in-line slider or in a lift-and-slide version, built around large glazed panels that run on a track rather than folding away. It suits openings where the priority is an unbroken view when the doors are closed and a smooth, low-effort glide when they are open, rather than the fully stacked-open configuration a bifold gives you.

Compared with the Cor Vision and Cor Vision Plus ranges we cover in our Cor Vision vs Cor Vision Plus comparison, the 4700 is the more conventional sliding platform. The 4900 Sliding HI alongside it trades some panel size for a slimmer 35mm central junction and class 4 air-tightness, while the 4700 keeps the larger sashes and the better U-value. We compare the two directly in our 4700 vs 4900 guide.

Sightlines and Panel Size

The 4700's interlock between panels is 47mm, so it carries a little more frame at the meeting point than the 4900 Sliding HI (35mm) or Cor Vision (20mm). In return, panel sizes run large: sashes go up to 2.5m wide by 3m high, at 280kg in-line or 300kg in the lift-and-slide version, which suits a modern extension where the brief calls for big panes of glass and a clean view of the garden.

Track Configurations

The number of tracks decides how many panels can slide and how they stack on opening, which depends on the width of the opening and how much of it needs to fully open at once. A two-track configuration gives the largest single sliding panel; more tracks let more of the opening slide clear when fully open. Cortizo's 4900 Sliding HI offers more track layouts than the 4700, including a 4-track option, so where a wide opening needs more of its width to open at once we compare the two. This is a survey conversation rather than a fixed spec, since the right track count depends on the exact opening.

Thermal Performance and Weathertightness

The 4700 is thermally broken, with Cortizo quoting Uw from 1.0 W/m²K (better than the 1.2 W/m²K of the 4900 Sliding HI), and it takes double glazing units from 26mm to 36mm. It reaches an A-rated energy category on a typical specification, with the exact figures confirmed at survey once glazing is chosen, and it is rated for sound reduction up to Rw 40dB. For weathertightness, the system uses a multi-point locking system and a compression seal along the running track, which copes well with a typical UK garden elevation. On an exposed, draught-prone elevation, the 4900 Sliding HI's class 4 air-tightness is worth comparing, and we will flag that at survey if your opening calls for it.

Colour and Finish

The 4700 is available across the full RAL colour spectrum with a dual-colour option, so the interior and exterior faces can differ. As with our other aluminium ranges, we run our own finishing checks in-house rather than relying on the supplier's paint booth alone.

Who the 4700 Suits

The 4700 is the right choice for most standard rear extensions and garden-facing openings where an unbroken glass view matters more than a fully open stacked configuration. Against the 4900, it is the one to specify for larger, heavier panels, for lift-and-slide operation, or where the lower U-value is the priority. Where a slimmer junction, class 4 air-tightness or a 4-track layout matters more, the 4900 Sliding HI is worth discussing at survey, and where the whole width needs to open, a bifold is.

We fabricate and install the Cortizo 4700 Sliding Patio door in-house at our Uxbridge workshop, cutting, machining and assembling each unit to the exact opening measured on site. All our installations are FENSA registered and carry a 10-year CPA insurance-backed guarantee.

Frequently Asked Questions

What is the difference between the Cortizo 4700 and 4900 sliding doors?

The 4700 takes the larger, heavier sashes (up to 2.5m by 3m), comes in a lift-and-slide version and has the better U-value, from 1.0 W/m²K. The 4900 Sliding HI is an in-line system with sashes up to 2.2m by 3m, Uw from 1.2 W/m²K, a slimmer 35mm central junction, class 4 air-tightness and more track layouts, including 4-track. We cover the full comparison in our dedicated 4700 vs 4900 guide.

How wide can a Cortizo 4700 sliding door opening be?

The maximum practical width depends on the number of panels, the track layout and the structural opening on your property. Each 4700 sash can be up to 2.5m wide by 3m high, at 280kg in-line or 300kg in the lift-and-slide version, and the overall width is confirmed at survey.

Is the Cortizo 4700 as slim as the Cor Vision range?

No. The 4700 has a 47mm interlock, while Cor Vision runs a 20mm central junction and Cor Vision Plus a 25mm one, so both Cor Vision ranges are visibly slimmer at the meeting point. Against Cor Vision, the 4700 offers a lift-and-slide version and a better U-value (Uw from 1.0 W/m²K against 1.3), while Cor Vision Plus beats both on panel size (up to 4m × 4m) and U-value (from 0.9). Which suits your project depends on how you weigh the sightline against those.

Can the Cortizo 4700 be specified in different colours inside and out?

Yes. The system is available across the full RAL colour spectrum, including a dual-colour finish with a different colour on the interior and exterior faces.

Does the Cortizo 4700 come with a guarantee?

Yes. Every Cortizo 4700 installation we carry out is FENSA registered and backed by a 10-year CPA insurance-backed guarantee.