Frequently Asked Questions

Below are some of the more common questions our customers ask us about our folding sliding doors - if you can't find an answer to your question, please contact one of our experienced team.



Doors and Frames

Sunfold Systems SFK70 Faceted Folding Sliding Doors create curved glass walls and dramatic architectual features.Can I have a low threshold (recessed) track?

  • We do offer a fully flush track that can be completely recessed into the floor leaving only a 5mm sloped rise and fall to and from the centre. The sealing method is on this track option is a double brush pile so water drainage and driving wind has to be a major consideration on installation.
  • Low threshold tracks are available on all our folding 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 & outside floor levels).

Why do I need horizontal transoms?

  • Transoms (also referred to as midrails) are required if the height of the door exceeds 2500mm. They are required for the stability of the door to stop the panels from flexing.

Why do I need trickle vents?

  • It is best to check with your local authority/building control as to whether or not you may require trickle vents as each area's rules can be different. 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.

Are the doors hung from the top or bottom?

  • Most of our folding door systems can either be top or bottom rolling, however tall doors and faceted doors do need to be top hung.

Can you manufacture faceted doors?

  • Yes, this is available on our SFK70 aluminium and SFK69 timber system. To be able to price these we will require the width & height of each panel as well as the radius of the curve.

What are your standard sizes?

  • We have no standard sizes as all our products are bespoke.

What is the weather rating on your products?

  • All our external products carry a severe weather rating.

Do you supply windows to match?

  • Yes we supply bespoke fixed or tilt and turn windows (tilting and opening in for ease of ventilation & cleaning) in the same profile as used on the doors. Please contact us if you would like a quotation.


Finishes

Sunfold Systems SFK82 Folding Sliding Doors with clear pine internal finish and RAL7016 aluminium powder coat externallyWhat are your standard / stock colours?

  • Standard / stock colours are different for each system that we offer. 
  • RAL 9016 Semi-Gloss (Traffic White), and  Silver Anodised Aluminium EV1 are standard with our SFK70, SFK70 Square, SFK82 (aluminium side), SFK50, SFK25 and SFK28 systems. 
  • 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 &silver anodised aluminium EV1 are standard on the SFT30, SFT70 & SFT140 systems.
  • Dual colouring is available so that the outside and inside are different.
  • We are able to offer any RAL powder coat non-stock finish on our aluminium frames. Non-stock colours add approximately between 8-12% onto the price.

What timber types are available?

  • Meranti, Pine & Oak
    N.B. Oak is an additional charge

What are the standard Sikkens stains and finishes on the timber?

  • Light Oak, Dark Oak, Teak, Mahogany Sikkens stains and Clear lacquer are standard timber finishes.
    NB: Clear lacquer cannot be applied to the external surface of timber doors.
  • Not all finishes are standard on all timber types. Clear lacquer is for Pine and Oak. Light Oak, Dark Oak and Teak Sickens stains are standard finishes for Oak and Meranti. Mahogany is also a standard finish for Meranti.
  • White Painted Finish (RAL 9016) is a standard finish on Pine and Meranti.
  • Dual colouring is available so that the outside and inside are different.
  • We are also able to offer any RAL colour painted finish or Sikkens stain on our timber frames as a non-standard colour at an additional charge.

Do you offer marine condition coatings on your aluminium and is it certified?

  • Aluminium can be coated to marine conditions and is certified by Qualicoat to meet the requirements for 'Seaside Class'.
  • Our systems also offer other Marine Treatment benefits.


Glass Information

Sunfold Systems SFK70 Folding Sliding Doors meeting at a corner with fixed panels. Sliding corner posts are available for complete corner openings Can you provide in-glazed Venetian blinds?

  • Yes we can supply in-glazed venetian blinds. The blinds sit within the cavity of the double glazed unit, standard slat colours include white, silver & cream.
  • We are able to offer them with battery operated electric and manual cord controls.

What glass do you use?

  • 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. 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.
  • We are also able to supply our systems with specialist glass types on request.

What are U Values?

  • The lower the U Value - the better the insulator. U-value is the measurement of heat transfer through a given building material, glass, etc. In the UK all U Values are quoted as W/m²K.
  • The thermally-broken aluminium systems have a general U-Value of 1.6 W/m²K to 1.8 W/m²K depending upon systems size and using our standard glass units.
  • The timber system has a general U-Value of 1.5 W/m²K to 1.7 W/m²K depending on systems size and using our standard glass units.

Do your doors comply with Document L?

  • All our external systems comply with the revised part of Document in April 2006


General Information

Sunfold Systems SFK70 Folding Sliding Doors Installed in the CaribbeanWhat are your delivery times?

  • Our delivery times vary throughout the year due to factory holidays or peak business periods. They are currently running at 7-14 weeks for supply & installation depending on the system type, colour and order complexity. For supply and delivery 6-13 weeks, again depending on the system type, colour and order complexity. Delivery times will not begin until we have received a signed contract and deposit.
  • If you are having a site survey or CAD drawings the dates begin once we have received the signed survey or CAD drawings as confirmation.

What are your payment terms?

  • Should you wish to place an order we require a 30% deposit with confirmation of your requirements, 50% becomes payable 14 days prior to delivery and the final balance payable prior to delivery or at time of installation.
  • We accept most forms of payment: Cheque, BACS, Credit & 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.

What is your warranty period?

  • Oders that are supplied and installed by us are covered for a period of 5 years. We do offer the option of upgrading this to 10years cover on our SFK70 aluminium system.
  • Supply and delivery orders are also covered for 5 years if a customer experiences a breakage, malfunction or is having difficulty in the operating the system. All finishes, components etc are guaranteed against manufacturing 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.

Can you supply to trade customers?

  • Yes we often deal with trade clients and have a pricing structure to offer trade prices.

Can I have a price list?

  • We don't offer a price list as all our doors are made bespoke which effects 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 by our online form with your sizes and the system type you would like a price for.

Do you deliver abroad?

  • Yes we are happy to arrange delivery or installation worldwide - we will need the full site/delivery address before being able to price this

Do you have a showroom?

  • Yes we have 2 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. See our contact us page for more information or to make an appointment.
  • Sunfold has a permanent exhibition in the National Self Build and Renovation Centre Swindon. We exhibit each year at national shows, see our website News for 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 doors.