The SUNFLEX sliding patio door review.

There are many sliding patio doors on the market from many good brands. The SUNFLEX sliding patio door is one of these. SUNFLEX already has a sought-after range of bifolding doors, and their sliding door is no exception. We review their aluminium sliding door offered in SVG30 and SVG83 models.

Our review focuses on the design, size capability and technical aspects of the products as well as where to use them. Several compelling reasons make this door worthy of consideration with systems such as Reynaers, Schuco and even the very latest ultra-slim sliding patio doors.

SUNFLEX sliding patio door
A contemporary sliding door with a choice of mullion sight lines.

A full review of the SUNFLEX sliding patio door.

Made in the UK, the SUNFLEX sliding door is a tried-and-tested door offering large sliding panels with bigger glass and better views compared to a folding sliding door. Patio doors today provide a strong visual appearance to the back of a house and especially with slim profiles and bold colours.

First of all, the SUNFLEX sliding patio door comes in two versions, namely the SVG30 and the SVG83. The product codes relate to the overall thickness of the door mullion, also known as the interlock.

This well-designed and quality-made sliding door comes in a choice of one or two panels for smaller apertures as well as three or more panels for bigger sized doors. For those thinking bigger, the product also creates the ultimate sliding glass walls with up to 8 panels on multiple tracks.  The SUNFLEX sliding patio door even allows open corner sliding doors and panels disappearing into a wall pocket.

Importantly, the SUNFLEX door is not just for new contemporary extensions.  It is entirely suitable as a replacement to old metal or plastic doors as well as patio doors in hardwood subframes.

As standard come thermally insulated frames, quality glass units as well as a big choice of colours.

Finally, there is a choice between a conventional inline sliding design or the latest lift and slide operation. 

Choosing between the SUNFLEX SVG30 and SVG83 models.

The two models are mostly the same on the outer frame, track and door leaves. You also get the same hardware, locking systems and patio door handles. The operating method of inline or lift and slide is also available.  Where the SVG 30 and SVG83 differ is the sight line of the door mullion.

The SVG 30 gives you a 30mm sight line and the SGV83 an 83mm sight line.  The choice of the product mainly comes down to the sizes of the doors and the technical capability. If sight lines are important in choosing a sliding door or a bifolding door, both the SVG30 and SVG83 provide thinner aluminium sight lines than even the 115mm sight line SUNFLEX bifolding doors lead the market with.

If your door is under 2800mm high or less than 6.25 square metres or less than 250kg per sliding panel, then you benefit from the 30mm sight line.  For those embarking on a Grand Designs type extension with bigger sliding door panels, then the SVG83 goes up to 3.2m high – again subject to technical considerations. However, with most standard size extensions needing patio doors, the SVG30 is suitable.  And this is where this slimline product stands out.

SUNFLEX sliding doors SVG30
SUNFLEX level threshold achieves the desired look with excellent weather protection.

A cheaper solution to the expensive ultra-slim sliding doors with SUNFLEX.

Ultra-slim sliding patio doors are the newest type of product on the market offering sightlines from 17mm up to 35mm or more.  These super thin, structurally bonded doors cost more and come with other manufacturing and installation considerations.  Conventional sliding doors like the SVG30 or 83 are dry glazed meaning unlike the ultra-slim doors, glazing is done on site, not in the factory.

With a 30mm interlock, the SVG30 offers a far simpler-made yet premium sliding door.  Structurally-bonded products such as the Infiniglide 6 Sliding Door, Alumen Cor-Vision Plus, Schuco ASS70 PD Panorama all offer interlocks between 24mm and 30mm.  Even the Metra NC-S 120 STH Slim Sliding Door Express bifolds sells as the XP Slide Panoramic costs far more and has the same 30mm sight line.

The other visual consideration with structurally bonded patio doors, as good as they are, is the very deep interlock. One the one hand it is thin to look at face on. On the other hand, it is much more prominent than a conventional slider often projecting back 150mm or more. This is for structural reasons as well as acting as a door handle with many systems.

Therefore, a product like the SVG30 offers similar thin sight lines of the much more expensive structurally bonded products at far less cost and in our view, looks aesthetically similar without the deep projecting mullion. See both types of doors and we think you’ll agree, there is not much difference.

SUNFLEX sliding patio doors designed as a frameless open corner and with a flush triple track threshold.

Design features and benefits of a SUNFLEX sliding patio door.

There are some design features worth highlighting with either the SVG30 or SVG83 patio door.

Bifolding doors are excellent for achieving a low, flush threshold. Some sliding door systems are challenging to set lower, compromising weather performance. SUNFLEX has engineered the door so that your internal flooring finishes flush with the low track of the door. As a result, you get the desirable flush floor with weather performance too. The product also offers its exclusive finishing trim, again rarely available with other sliding doors. This trim provides a neat detail between the flooring and the track as well as ensuring a proper clearance.

Further enhancements to the product include design details giving a bigger clear opening on three panel doors than other systems. Another useful feature on three panel doors is SUNFLEX making each panel a slightly different size. Where no external handle is fitted, the doors fully open and stack flush. Again, something not always available with other systems.

For doors sliding into a wall pocket and disappearing from view, there is another neat touch. A purpose-made profile closes off the gap between the door and the structure. Consequently, the doors look entirely flush with the wall. Again another neat touch.

And if you’re considering a cornerless bifolding door, the same frameless open corner is possible with these sliding doors too.

Patio door security, weather performance and hardware options.

The locking system on these doors has a five-point lock with mushroom headed cams, ensuring a tight seal and optimum locking point. Other security enhancements include internal glazing preventing removal of the glass from outside. The sliding panels also have an anti-lift feature. This prevents anyone forcing the panels up off the track.

Toughened glass usually comes as standard with any door. Upgrade the glass to laminated to meet Secured by Design standards as well as the latest Document Q of the Building Regulations for new homes. 

Four different handle options provide choice available in matching or , contrasting colours and satin stainless steel. Door colour options include grey or black colours as well as the full range of RAL colours or different colours inside and out.

SUNFLEX SVG30 sliding patio door
SVG 30 patio doors sliding into a wall pocket and stacking open completely flush.

Reasons to buy a SUNFLEX sliding patio door.

Our website reviews many different brands and systems, and this is certainly one door to consider with other quality brands. However, there are some standout reasons to consider either the SUNFLEX SVG30 or SVG83 seriously.

First of all, it’s by SUNFLEX, one of the premier brands in the UK with award-winning and very slim bifolding doors.  These doors offer the same benefits of one manufacturer with the associated consistent quality.

Another reason is the enhancements. The product is engineered to cover the fine detail other systems may miss. For instance, the flush stacking panels or the low threshold with weather resistance. Designed to disappear into a wall pocket or as an open corner door, there is excellent attention to detail.

The price of these doors compared to the structurally glazed products on the market is another compelling reason. Many ultra-slim doors use the Cortizo or other European systems. However, these do come with a more complicated installation and a higher price.  The SVG30 especially offers similar thin lines giving you an alternative to the highly desirable slimline doors very much on-trend.

Considering a Schuco ASS70, a Reynears CP30, CP155, an Edgeglide or similar quality product?  We suggest you also get a price on the SUNFLEX sliding patio door and compare the features and specifications.

Contact us for further information.

For further information, as well as where to buy SUNFLEX products and to get a quote, get in touch using our contact form.

Published on December 21, 2018

Reader Interactions


  1. Louise says

    Hello Nick

    Looking to install slim line sliding patio door system going on your recommendation of Sunflex.

    Are there any installers in my area of Alton Hampshire .


  2. Elwyn Evans says

    Thanks Nick for such useful advice firstly

    Our location is on the Coast of Llandudno Bay in North Wales.

    We are constantly attacked by Sea breezes and there is inevitably a lot of salt in the air as well, so the hardware must be able to withstand the effects of sometimes brutal winter weather.

    • Nick Dardalis says

      Hi Elwyn, you’re best off speaking with Sunflex on this one so they can correctly advise you on costs and what you get hardware-wise on coastal doors. Also worth looking at Reynaers doors as well as Schuco, widely used in coastal environments.

      The below should be able to help you.
      0800 587 4068
      North West Bifolds 
      12 Crucian Way
      L12 0AW

      Altitude Aluminium
      North West Head Office:
      Aviation Park
      Access House
      Flint Road
      Chester, CH4 0GZ
      01244 529 199

      Hope this helps, please don’t hesitate to get in touch if you’ve any questions or need further information. 
      Kind regards

  3. Alicia says

    Thank you for this. I have been in contact with Park FarmsDesign who stock and supply the sunflex doors.

    Just choosing between the sunflex svg30 and visoglide2000. Do you have any preference.

    BTW this is a great is and has helped hugely!

    • Nick Dardalis says

      Hello Alicia, thanks for your question and kind comments on our website.

      The Slide 2000 by Smart Systems is a tried and tested product and a reliable patio door. It is, however, quite an old model. The Sunflex product in our view is newer, better engineered and more modern looking. The 2000 model is quite rounded in appearance and typical of many European sliding doors so it’s a choice of aesthetics too as well as engineering.

      We know Sunflex has done a lot of good work improving the SVG30 product and we think this is the better product even though it is based on (an improved) Visogolide system.

      Hope this helps.
      Kind regards

  4. Alicia says


    Based in Cambridge and looking for a stockist/installer of the sunflex svg30

    • Nick Dardalis says

      Hello Alicia, thank you for your enquiry to the Aluminium Trade Supply Website. I think the below serve your area, but worth checking with Sunflex directly.

      Chase Window Company (Hertfordshire Showroom)
      Cobury House,
      Unit 1, 11 Pindar Road,
      Herts, EN11 0BZ
      020 8366 6500

      The details for Sunflex to get a local dealer and view the doors

      Unit B1
      Rhombus Business Park
      NR6 6NN
      01603 258649 (Any enquiries) for a local dealer.

      Hope this helps, please don’t hesitate to get in touch if you’ve any questions or need further information. 
      Kind regards

      • Alicia says

        Thanks for this.
        Do you have any advice on deciding between the smart system visoglide 2000 or the sunflex svg30

  5. Elwyn Evans says

    Hi there,

    Thanks for all your advice on this website

    Looking for a good quality Patio Sliding Door system that will withstand strong winter sea breezes and salt effects on the Door hardware.

    The opening we are looking to fill is approx: 8.5 M long by 2.3 M high

    I’m swayed towards your Sunflex recommendation but whilst my budget is not as big as some, I need to concentrate on also getting the correct hardware because we live right on the Beach – without compromising on the quality of the Sliding mechanism – thx in advance

    • Nick Dardalis says

      Hello Elwyn thanks for your question. Any of the current systems meet very good weather ratings so the key area is the overall quality of the fixtures and fittings to ensure they resist the coastal location effectively. Another consideration is the durability of the powder coating and whether you go for a proper warranty on the doors instead of the thicker paint finish, that comes without a warranty and often referred to as “Marine Grade”.

      My advice is to choose an installer with some experience in these installations that can advise you properly and answer your questions as well as provide the right product for you.

      Sunflex is a good place o start with their SVG door but if you’d also like to get in touch via our contact form with your location I can try to suggest some other suppliers too. But you will get what you need with the sunflex door too.

      Hope this helps
      Kind regards