Sunvista Frequently Asked Questions

In this section, we hope to address any questions you might have regarding the Sunvista sliding door and window system. Please refer to our 'Typical Details' section for further information.

List of Questions

  1. How secure is Sunvista?
  2. How does the system drain if it is in the floor?
  3. What maintenance is required?
  4. What warranty is offered?
  5. What configurations are available from Sunvista?
  6. With so much glass will I have a problem with solar gain?
  7. What is the manufacturing period?
  8. Can blinds be fitted within the system?
  9. What frame colours are available?
  10. What U-values can be achieved?
  11. Can the doors be alarmed?
  12. How do the doors slide?
  13. Can doors be automated?
  14. Can doors slide into a pocket?
  15. Does the system provide good sound insulation?
  16. Are bi-folding doors available?
  17. Does the system incorporate trickle ventilation?
  18. Can the system be used for high level applications?
  19. Does Sunvista come under the FENSA scheme?
  20. Can Sunvista be triple glazed?
  21. Can we buy Sunvista and install it ourselves?
  22. What are the payment terms?

How secure is Sunvista?

Security is one of the most important issues to consider when choosing this type of product and Sunvista is probably more secure than any comparable system. Sunvista’s unique multipoint locking system has passed the extremely intensive PAS24:2016 (enhanced security performance requirements for door sets and windows in the UK) which is the most advanced security testing method for residential windows and doors. It is the base testing method for windows and doors to be classified as ‘Secured by Design’.

There are four particularly vulnerable areas of a sliding door system and Sunvista has considered them all.

Lifting doors out: All doors are fitted with anti-lift devices to prevent them from being lifted out.

Lever/crowbar attack: This type of attack forms part of the PAS 24 testing which Sunvista passed. The frames are usually fully or partially concealed within the surrounding structure and the sliding sections are such a secure and tight fit that a crowbar attack is virtually impossible.

Locking: All Sunvista doors are fitted with three double 5mm thick stainless steel double hook locks which are strategically concealed within the frames. The location of these is not visible from the outside meaning that intruders would not know which areas to attack. The multi-point locking profiles do not need to be key operable to achieve the PAS 24 standard, however, a key operable option is available. This should more than satisfy your insurance company.

Smashing glass: As a minimum, double glazing units installed will comprise two leaves of 6mm thick toughened glass which is up to five times stronger than standard float glass and is extremely impact resistant.

How does the system drain if it is in the floor?

TThe Sunvista floor track is designed to be fully recessed within the floor and the threshold to be flush and transition free. Even though the base track is below ground level it is extremely unlikely that water will ever breach the simple but effective drainage system even in the heaviest rainfall. In most cases water drains out into an in-ground drainage system situated within raised flooring (typically decking or slabs) outside the building seal. The base tracks are fixed on bespoke adjustable brackets and no fixings ever penetrate the track which ensures that water can never seep through.

What maintenance is required?

Sunvista is a fully tested system and has been designed to be virtually maintenance free. Not only has Sunvista been independently tested for weather tightness and security but also for durability and long term use. The concealed wheel carriages have been designed and engineered to be maintenance free using corrosion free components; these as well as the integral and elegant locking handles have been tested to 50,000 locking actions.

The bottom track requires an occasional wipe over with a dry cloth and that is all the maintenance that should be necessary.

An operation and maintenance manual will be provided following an installation of Sunvista doors.

What warranty is offered?

We list below the anticipated life expectancy and guarantees available on key components. We would define life expectancy as 'the period of time a component is expected to perform in accordance with the performance specification.'

Subject to reasonable wear and tear, we warrant the glass and components installed on this project will be free from defects in materials and workmanship which would render the product unserviceable or unfit for ordinary recommended use from the date of installation as follows:-

Insulating units against failure of the air seal and that each unit will be free from material obstruction of vision as a result of fogging or film formation on the internal surfaces. We warrant laminated glass against de-lamination resulting in materially obstructed vision through the laminated glass. All insulating units are warranted in accordance with the above for a period of ten (10) years.

Powder coating finishes are guaranteed for a period of ten (10) years against defects resulting in cracking, peeling and other loss of adhesion in general environments. Powder coated surfaces should be cleaned with mild detergent soap and water. Any chips or scratches must be repaired immediately and not left exposed to the elements. Please let us know at the time of order if your project is in a marine environment and we will supply a thicker coating.

Hardware components (locks and wheel carriages) are guaranteed for a period of ten (10) years. For the warranty to be valid the stainless steel track is kept clean (see the maintenance section above). If dust and debris is allowed to build up in the Sunvista base tracks it can cause damage to the wheel carriage and prevent the doors from sliding. If this does occur any warranty will be void and any rectification work would be chargeable. Removal of dust is easy; a simple wipe with a dry cloth should be all that is required. It is important for the sliding door’s smooth movement that the track is kept clean.

The maintenance procedures need to be carried out as often as necessary to prevent deterioration in the installed environment, however, we recommend that, as a minimum, the maintenance frequency in non-marine environments should be every three (3) months.

All hardware products should be cleaned and maintained as recommended above and as frequently as necessary. In event of a warranty claim user must be able to present maintenance schedule as recommended above.

Any failed product within the guarantee period will be replaced free of charge including delivery subject to the product having been used under normal conditions. Unless we installed the product our liability will be limited to replacement of goods only.

What configurations are available from Sunvista?

Any variety of configurations and sizes can be achieved using two, three and four tracks, including fully opening corners and pocket doors with the largest individual sliding panel normally being 3500 x 3000mm. Fixed panels including frameless glass corners are available up to a width of 6000mm.

Please refer to our 'typical details' which indicate some of the more usual options available. However, if you require something different to those shown please ask.

With so much glass will I have a problem with solar gain?

Depending on the orientation of the glass doors additional solar protection might help. The further away from due south the glazing faces the problem of summer overheating is reduced. UV rays, in particular, are also much stronger when the sun is high in the sky. Neutral (non-tinted and virtually invisible) solar control coatings can be incorporated within the insulating units which will help protect your home by blocking out the harmful UV rays from the sun. These will not noticeably affect the level of brightness and will help to reduce solar gain. There are various types of solar control coating, however, the most popular is a neutral 70/35. See image below for performance details.

How long does Sunvista take to manfuacture?

Depending on what is involved on your project, in particular the type of insulating units and on our workload at the time of order we would expect to fulfil most orders within 6 weeks of receiving signed off drawings. Projects involving four track systems can take longer.

Can blinds be fitted within the system?

Blinds do not yet form part of the Sunvista system. Separate blinds which provide privacy and shading, such as those manufactured by Silent Gliss (, can be installed in recesses inside or outside the frame.

What frame colours are available?

The aluminium frame profiles can be powder coated to any standard non-metallic RAL colour. Metallic colours are available at an additional cost. Click here to view the standard colours. Please note that colours and shades can vary slightly.

What U-values can be achieved?

A 'U' value is a calculation of the amount of energy that can escape through the external envelope of a building. The energy loss is calculated in Watts per m² Kelvin (W/m²K). The lower the 'U' value, the better the thermal performance.

Until recently the glazing element would have been one of the weaker elements when compared to more solid materials, however, Sunvista installs high quality insulating units with warm edge spacer bars, soft coat low ‘E’ (low Emissivity) coated glass and argon gas filled cavities that achieve a centre pane 'U' value of 1.1 W/m²K as standard.

Low ‘E’ glass is a must for all insulating units in order to achieve the thermal performance criteria demanded by Building Regulations Part ‘L’. Low ‘E’ glass has an ultra thin coating on the internal face which reflects the heat back to its source.

A window is not like a brick wall where the focus is on keeping the cold out and the heat in; efficient insulating units can actually contribute more energy to the heating of the building than is lost through the window.

Does the system provide good sound insulation?

Noise has become an omnipresent health hazard particularly in urban locations or in the proximity of railways, roads and airports. Sunvista's double glazing provides good sound insulation as standard, however, if noise is a particular problem Pilkington 'Optitherm' acoustic glass can be incorporated. Click here for more information.

How do the doors slide?

Sliding panels run on bespoke wheel carriages which incorporate concealed, low resistance, top quality stainless steel ball bearing rollers which create a smooth and easy door operation. These rollers are virtually maintenance free.

Can doors be automated?

Sunvista doors can be automated.

Can doors slide into a pocket?

Doors can slide into pockets on one or both sides and on one or two tracks. They can even slide over the outside of the building if there is no room for an internal pocket. Please refer to our 'Typical Details' section for more information.

Can the doors be alarmed?

Most alarm contacts and sensors can be incorporated within the Sunvista system. We can work with your alarm company and, depending on the component type and size, will try to accommodate your components within the frame. Please let us know your requirements and the category of security required.

Are bi-folding doors available?

Unfortunately these are not currently available from Sunvista. Please visit the ‘bi-fold’ section on our website.

Does the system incorporate trickle ventilation?

Trickle vents are very small openings which are usually integrated into window frames and allow air into the property. Gentle airflow helps prevent condensation, mould growth and dampness. Trickle ventilation can be discreetly incorporated in Sunvista sliding doors, if necessary.

Can the system be used for high level applications?

If Sunvista is installed at high level and is required to act as a barrier from falling, laminated safety glass should be installed as part of the insulating unit and will provide anti-fall protection. 'Juliet' and other types of balustrades can be introduced as another means of anti-fall protection.

Can Sunvista be triple glazed?

The already impressive ‘U’ values can be improved even further by introducing an invisible, high performance film which acts as the third leaf of a triple glazed unit and can improve the already impressive thermal performance, if required.

Does Sunvista come under the FENSA scheme?

It is not required to. FENSA stands for the Fenestration Self-Assessment scheme which was set up by the Glass and Glazing Federation to ensure that replacement windows meet the Government’s Approved Documents Parts L1B and K4 (England) or N (Wales) (safety in relation to impact). The Sunvista sliding door system does not come under the category of ‘replacement windows’ and as such the installer is not required to be FENSA registered. However, it should be noted that Sunvista more than meets these requirements.

Can we buy Sunvista and install it ourselves?

Only properly trained installers are allowed to install the Sunvista system. We need to be confident that the product is installed in accordance with our installation instructions and that you, our customer, will be satisfied with the operation of Sunvista for years to come.

What are payment terms?

Unless agreed otherwise our standard terms are 25% of the contract value payable with order or receipt of signed contract; 65% payable ten days prior to installation and the balance payable on completion of the work. All payments are to include VAT at the applicable rate.