Home > FAQs
When choosing your folding sliding doors, doors or windows, we realise you'll have lots of questions to make sure you choose the best option available to suit your requirements. We've therefore put together a selection of our most frequently asked questions to help you on your way. However, if your question hasn't been answered please do not hesitate to contact us to speak to one of our door or window experts.
Folding sliding doors
We do offer a fully flush track with our folding sliding doors that can be completely recessed into the floor leaving only a 5mm sloped rise and fall to and from the centre. The sealing method on this track option is a double brush pile so water drainage and driving wind has to be a major consideration on door installation.
Low threshold tracks are available on all our folding sliding door systems - on some you can even have a low threshold whilst still maintaining the weather rating (on these you will require a difference of 10-15mm between the inside and outside floor levels).
Transoms (a horizontal crosspiece over a door or between a door and a window above it) are required if the height of the door exceeds 2500mm. They are required for the stability of the folding sliding door to stop the panels from flexing.
It is best to check with your local authority/building control as to whether or not you may require trickle vents with your folding sliding doors; this may vary dependant on the situation. Trickle vents are usually required if there is no other form of ventilation in a room.
Our in-glazed trickle vents provide ventilation of 4100mm² equivalent area (as per BS EN 13141-1:2004) per metre of vent. Our through-frame trickle vents provide ventilation of 2500mm² equivalent area (as per BS EN 13141-1:2004) per vent.
Most of our sliding folding door systems can either be top or bottom rolling, however tall doors and faceted doors do need to be top hung.
Doors & windows
Yes we supply bespoke fixed or tilt and turn windows (tilting and opening is for ease of ventilation and cleaning) in both composite and aluminium to complement our doors. Please contact us if you would like a quotation.
Yes we often deal with trade clients and have a pricing structure to offer trade prices.
Yes we have the facility to deal with large scale projects through our commercial division Sunfold Commercial, click here to visit our website to find out more.
Yes we have two showrooms, one in Wymondham, Norfolk and the other in Chiswick, London. Both can be viewed on an appointment only basis to ensure that someone is available to help you. Contact us for more information or to make an appointment.
Sunfold Systems also has a permanent exhibition in the National Self Build and Renovation Centre in Swindon. We exhibit each year at national shows, contact us for details of the next planned event. We also have a network of customers who are very happy to open their homes for other customers to see their folding sliding doors, interior doors, exterior doors or windows.
Examples of our door and window products can also be seen at Kingspan Potton’s Self Build Show Centre in St Neots, Cambridgeshire.
Colours & finishes
Q - What standard/stock colours are your folding sliding doors, sliding doors, stacking doors and windows available in?
Standard and stock colours are different for each door and window system we offer using mainly RAL and anodised standard finishes.
RAL 9016 semi-gloss (traffic white), and silver anodised aluminium EV1 are standard with sliding folding door systems SFK70, SFK70 square, SFK82 (aluminium side) and SFK50, but also with sliding stacking door systems the SFK25 and the SFK28.
RAL 7016 matt (anthracite grey), RAL 9016 matt (traffic white), RAL 9005 matt (jet black), DB703 (dark metallic grey) are additional standard colours available for the SFK70 and SFK70 square system.
RAL 9016, 9010, 1013, 6005, 8017, 7016, 7040 and silver anodised aluminium EV1 are standard on the SFT30 internal folding sliding door system, and the SFT70 and SFT140 sliding door systems.
Dual colouring is available for doors and windows so that the appearance outside is different to inside.
We are able to offer any RAL powder coat non-stock finish on our aluminium door and window frames. Non-stock colours do carry an additional charge. A full list detailing all RAL colours can be found here. Please contact us if you require further information.
Meranti, Pine and at an additional charge, Oak
Light oak, dark oak, teak and mahogany Sikkens’ stains and clear lacquer are standard timber door and window finishes, however, clear lacquer cannot be applied to the external surface of timber doors or windows.
Not all finishes are standard on all timber types. Clear lacquer is for pine and oak. Light oak, dark oak and teak Sikkens’ stains are standard finishes for oak and meranti doors and windows. Mahogany is also a standard finish for meranti.
White painted finish (RAL 9016) is a standard finish on pine and meranti doors and windows. Dual colouring is available on our doors and windows so that the outside and inside can be different. We are also able to offer any RAL colour painted finish or Sikkens stain on our timber door and window frames as a non-standard colour at an additional charge.
Aluminium can be coated to marine conditions and is certified by Qualicoat to meet the requirements for 'Seaside Class'.
Marine treatment protects against saline environments. Frames are protected from corrosion by a specialised process that increases the bond between the powder coating and the frame.
Yes we can supply in-glazed venetian blinds for any system which will incorporate 28mm double glazed units such as windows, folding sliding doors and sliding doors with small panels. The blinds sit within the cavity of the double glazed unit, standard slat colours include white, silver and cream. We are able to offer venetian blinds with battery operated electric and manual cord controls.
Our standard 28mm unit comprises two panes of 4mm clear toughened glass, with an argon gas filled 20mm cavity. The inner pane is equipped with a Low E (soft coat) thermally efficient coating. Glass units are manufactured to BS62606A and BS5713.
We also offer Reflex solar control glass and glass with in-glazed manual or battery operated electric blinds. Triple glazing options are available on select products, contact us to find out more. We are also able to supply our systems with specialist glass types on request.
U-values measure how well a building component, such as a window, keeps heat inside a building. Basically the lower the U-value - the better the insulator. In the UK all U-values are quoted as W/m²K.
Thermally-broken aluminium door systems, such as the SFK70, have a general U-value of 1.6 W/m²K to 1.8 W/m²K depending upon the system size and using our standard glass units. U-values as low as 1.4 W/m²K can be achieved using Reflex+ glass (based on 1.1m wide x 2.4m high).
Timber (SFK69) and Aluminium clad timber (SFK82) door systems have a general U-value of 1.5 W/m²K to 1.7 W/m²K depending on the system size and using our standard glass units. U-values as low as 1.2 W/m²K can be achieved using Reflex+ glass (based on 1.1m wide x 2.4m high).
The SFCW composite window system on a standard window size of 1230mm x 1480mm has a general U-value of 1.4 W/m²K for double glazed units.
In some cases, triple glazing can be used, which reduces the U-values achieved even further. Contact us for further information.
More details about U-values can be found on the RIBA website by clicking here.
Payment & warranty
We welcome payment by BACS. Our bank details can be found on our invoice.
We accept the following credit/debit cards over the phone – VISA debit or credit, MasterCard debit or credit, Electron, JCB, Maestro, Solo and American Express.
We will accept cheques - however, we ask that you allow up to ten working days for this process.
Should you wish to place an order we require a 30% deposit with confirmation of your requirements, 60% becomes payable 14 days prior to delivery and the final balance payable prior to delivery or on completion of installation.
We accept most forms of payment: cheque, BACS, credit and debit cards. All payments made using a UK credit card will be subject to a 1% surcharge, cards registered outside of the UK will be subject to a 2% surcharge. There are no charges for payment made using a UK debit card.
We don't offer a price list as all our folding sliding doors, interior doors, exterior doors and windows are made bespoke which affects the pricing, we will however be happy to provide you with a quotation if you could inform us of the width and height that you require. Alternatively you can contact us with your sizes and the system type you would like a price for.
On orders that are supplied and installed by us, we guarantee the product in its entirety as well as the integrity of the installation. These are covered for a period of five years and on additional systems, for example, the SFK70 aluminium sliding folding door for 10 years.
Supply and delivery orders are also covered for either five or ten years, dependent on the product, if a customer experiences a breakage, malfunction or is having difficulty in operating the door or window system as a result of manufacture defects. However, if problems arise as a result of poor or incorrect installation, we do offer a chargeable service to rectify any problems.
Some additional components such as in-glazed blind controllers and electrical roof vent openers can have a reduced warranty period. Any variations like this will be detailed on the guarantee certificate issued once the job is complete.
Due to the exceptionally high quality of our bespoke products we do not offer set lead times. Each job is unique and therefore the time it takes to produce and install can vary significantly depending on the system type, colour and order complexity. We always strive for the shortest possible lead times, but without compromising on our high standards of manufacture or installation. Please contact us for more details.
Our SFK20:20 system is currently available with improved pricing and lead times as short as 4 weeks.
Yes we are happy to arrange delivery or installation worldwide - we will need the full site/delivery address before being able to price this.
Yes, a full technical on-site survey can be provided to ensure all aspects of the building, the environment and legislations are taken into account, for a nominal fee.
Yes if required. CAD drawings will show the overall design of your property incorporating the chosen Sunfold System, along with showing structural dimensions, manufacture dimensions and any extra ancillaries. If you choose to have a site survey, CAD drawings are included as part of the package.
Yes, we can accommodate any requirements you have – supply only, supply and install, survey and supply or the complete package of survey, supply and install. Your Sunfold sales representative will be able to advise you.
Good customer service is immensely important to us. We will be on hand to answer any questions you have at any stage of the project. Contact Sunfold’s Head office telephone number: 01953 423423. You will be directed to the correct department depending on the nature of the enquiry.
Once we have finished your work, we will send you an e-mail asking you to complete an on-line survey. We would really appreciate you spending a few moments answering the questions. It is only with your feedback that we can continue to maintain and improve our business. If your job is finished, but you have not completed a survey, please do, all entrants are entered into a free prize draw. Click on the relevant link below. Many thanks.
Many of the products on the site have technical details available. To access to our technical documents please create an account by clicking the red button at the top of any page and filling in the details. Wait for activation and then access the specific technical details via our product pages. Alternatively visit the Technical download page. If you have any problems or would rather receive the information by email please contact email@example.com or call us on +44 (0)1953 423 423.