Bifolding Doors Glossary of Terms

At Aspire Bifolds we offer eight different bifolding door brands, yet these share many common names and descriptions. A bifolding door is a complex product with advanced engineering and design, giving you large span doors that effortlessly slide and fold. We have created a simple bifolding doors glossary of terms.

bifolding doors glossary of terms

Bifolding doors Glossary of Terms.

If you are thinking about having a new bifolding door, you may come across terms and descriptions you are not familiar with. We explain what these mean to help you understand bifolding doors better.

Bifolding door names.

Bifolding door is the most common term to describe a series of door panels that open and fold there are other names used. Concertina doors, accordion doors, slide and fold doors, slide and turn doors and folding doors are all common names used to describe them.

Bifolding door configuration.

The bifolding door configuration refers to how your door is designed and the number of panels. The configuration of your doors also applies to the sliding direction, whether they open in or out and the opening arrangement of one or more leaves.

Bifolding door sight lines.

If you are thinking about visible aluminium you get with bifolding doors, this is known as the sight line. The sight line applies to the door profile visible when the doors meet in the middle as well as at the head, the threshold and the sides of the door.

Our range of bifolding doors includes the latest slimline Visofold 6000 door that is one of the slimmest you can buy today. All our doors offer narrow sight lines to maximise the light and views to the outside.

Bifolding door outer frame.

The bifolding door outer frame you will see fixed to your structure on the one side and is also where the door panels are held in place. The outer frame determines whether your doors open in our out as well. On the outer frame, you will find the locking keeps, door hinges and other components. Outer frames also hold the seals and gaskets than enabling closed doors to be very weather resistant.

Bifolding door jambs.

The jamb on your bifolding door is the correct expression for the vertical sides of your frame, left and right. Some of our doors such as Origin bifolds with a 20 year guarantee, offer a fixed jamb; our Schuco doors offer a moveable, adjustable frame jamb. There is no better method, just the different design features found in individual bifolding doors.

Bifolding door threshold and cill.

The threshold or cill found on a bifolding door is on the base fixed to your floor. Within the threshold, you will find the rollers, carriages and other weight-bearing components.

Under your threshold, you will find an aluminium extrusion called a cill. This is designed to move the water away from the door and to the outside. Whether your door needs a cill or not depends on the individual site survey carried out with every property as no two doors are the same.

Polyester powder coating.

Aluminium bifolding doors are available in over 200 different colours thanks to the benefits of polyester powder coating.

Also known as ‘powder coated’, this is a dry powder applied to the aluminium profile at the same time as an electrical charge is passed through it. Upon application, the aluminium sections are baked in a special oven to cure the paint and give it an extended lifespan.

Powder coating has been used in the colouring and finishing of aluminium for over forty years and has proven its dependability with a huge colour choice. It is the best way to paint a bifolding door.

Bifolding door seals.

Study any door, and you will see rubber, wool or other materials designed to provide a tight air and water seal. Seals are found on the outer frame, the door jambs and the door leaves, depending on the product and how it is designed to resist the weather.

Polyamide Thermal break.

The polyamide thermal break is an insulator inserted between the inside and the outside of all your door profiles to insulate them and bridge the cold. Bare aluminium is not a good conductor of heat and cold. Polyamide thermal breaks are now used in all modern folding doors to give aluminium excellent energy efficiency and thermal performance. The polyamide thermal break has also enabled aluminium doors to come with different colours inside and out.

It is typical for the thermal break to be black, although sometimes this can be painted over. The thermal break is only visible as you look at the frame or door sash with an open door. You cannot see it when the doors are closed.

Traffic Door.

The traffic door is one of the things you will need to consider when deciding on your bifolding door configuration. A traffic door works just like a regular door being independent or part of the folding panels.

The advantage of the traffic door on a bifold is that it enables you to use your doors all year round without having to fold all the panels back. A bifolding traffic door is ideal for letting pets out, taking the washing out to dry, for ventilation or using your bifolding doors all year round.

Slave door leaves.

In a door with a traffic door, the remaining doors are referred to as slave door leaves. Some people may refer to them as intermediate leaves.

Bifolding or carriage.

The bifolding door carriage contains the wheels that sit within the bifolding door threshold enabling the smooth sliding action. Some carriages carry four or six wheels. Some systems have the carriage visible; others conceal it. There is no best method as long as the weight of the bifolding doors is always at the bottom.

Slave leaf Shoot bolts.

A bifolding door contains a master door leaf housing the highly secure multi point lock and lever handle. The remaining leaves also need to lock, and these are fitted with a shoot bolt lock. The shoot bolt is operated by a rotating slim handle that engages secure rods in the head and threshold. This gives consistent locking points throughout the door set.

Bifolding door slave handle.

To pull the doors closed and operate the slave leaf shoot bolt, a D-Handle or pull handle is provided. With one hand you hold the slave leaf tight to the frame and with the other, you engage the shoot bolt.

Our Ewell Showroom showcases some of the latest bifolding doors available on the market today. Contact us or pop in and see us and let us demonstrate our bifolding doors glossary of terms and other features found in quality bifolding doors.

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What our customers say:

excellent dealings from start to finish, knowledgeable sales team and superb fitters
Roy H.
Roy H.
08:22 02 Aug 21
From the first phone call, a visit to the showroom, through to the site survey and installation, the Aspire team have been unfailingly both very professional, problem solving and friendly. They delivered a great product and service, at a good price, on time, with flexibility, diligence and a smile, and that in our experience is almost unheard of these days.We will definitely turn to Aspire again when we next need windows etc, and can't recommend them enough.
Chris Y.
Chris Y.
09:06 13 Jul 21
Brilliant Service from start to finish. From the time we got in touch for initial quotation for our bi-folds doors until delivery of the products and installation this company was a pleasure to work with and highly recommend this company. The entire team we dealt with including James, Danny and his installation team, Peter, Frankie have been very friendly, courteous and professional. Always punctual and did their best to meet all our requirements. Excellent workmanship and quality products. Good competitive prices too. Very pleased with everything and Thanks very much Aspire Bifolds for a job well done.
Buddhika B.
Buddhika B.
10:05 18 May 21
Super impressed with the level of service and how quickly they got the job done. Really happy with our new bifolds fitted just in time for spring!Would definitely recommend
Greg P.
Greg P.
09:50 05 May 21
Aspire did the most beautiful job in our house. The installed our windows a few months ago, and I couldn't be happier.They were always happy to answer to our question.They came at 8 o'clock and installed the windows very swiftly with a very clean and tidy result. They decorated afterwards around the windows and you couldn't tell those weren't the original windows as the result was so good.We have a toddler in of the rooms they were installing the windows and they accommodated their work around his naps which was brilliant.If you are looking for anything window or door related look no further, I will definitely recommend and if needed use them again.
GEMMA M.
GEMMA M.
10:20 28 Apr 21
Aspire supplied the most beautiful 7m sliding doors for my extension. The doors are great quality and all the fitting and snagging very professionally handled. Would not hesitate to use this company. Thank you.
Jo J.
Jo J.
15:33 16 Mar 21
I would recommend Aspire Bifolds. We love our bifolds and the service we received was great.
Karen A.
Karen A.
07:40 16 Mar 21
The team were so brilliant, helpful and lovely to deal with to supply and fit of our new steel look heritage doors. We are delighted with them and heartily recommend using Aspire! A great experience all round.
Andy P.
Andy P.
11:15 05 Feb 21
Best Bifold supplier in Surrey
Martin J.
Martin J.
19:06 06 Jan 21
Great Service from Aspire, with comprehensive knowledge on bifold systems and went with the ORIGIN product. Hassle free communication throughout contract and install just before Christ.as 2020.
Simon C.
Simon C.
16:01 04 Jan 21
We were recomended to Aspire by our carpenter who was building a garden room for us, and we were not dissapointed.From the initial meeting to the completion of the work the company , and especially John Small, and the lads that came to install the doors on one of the wettest days of the year, have been excellent.The Bifolds are amazing. They look so good, and when they open and close they sound solid and beautifully made.Superb job. Thank you.
Simon B.
Simon B.
08:12 25 Nov 20
I don't usually write reviews but Aspire have been an absolute pleasure to deal with from start to finish. After replacing my neighbours sliding doors they came highly recommended. The lady on the phone was extremely helpful and understood my requirements, and my quotation was turned around quickly. I had some technical questions regarding the threshold; and unlike other companies I dealt with, I was not treated as a nuisance and Ji (I hope I spelt this correctly!) talked me through everything. The surveyor arrived within a day of me signing and despite the current situation with many delays, they still installed within the quoted lead time!The Schuco bifolds we now have look amazing and we are so thrilled we went with Aspire Bifolds!Thanks alot Ji and Team.Cliff
Cliff Bentley T.
Cliff Bentley T.
14:33 04 Nov 20
From the very beginning of discussing what products I’d like, through to survey and fitting, Aspire have been fabulous. Very happy with both the products themselves and the service throughout, would thoroughly recommend!
Thank you so much!
Cat P.
Cat P.
10:56 23 Sep 20
Aspire were great to work with and we are delighted with the finished product. We got bifolds, skylight, large side windows and french doors all for a highly competitive price. We had some unavoidable delays due to the pandemic but we were always kept in the loop with what was going on with our order. we are extremely pleased with the quality and value we got through working with them.
Frankie H.
Frankie H.
12:32 11 Sep 20
Very professional. Do a great job.
Rupert P.
Rupert P.
08:23 11 Sep 20
I would absolutely recommend Aspire Bifolds. They provided a great product at a reasonable price. Installation team was friendly and professional. They installed in less than a day.We also encountered a small issue with the measurement of the doors, but the leadership at Aspire was quick to cover additional costs incurred to rectify the issue. We really appreciated their professionalism on this matter.
Tim S.
Tim S.
06:54 10 Sep 20
Huge thank you to Aspire Bifolds for our external steel look doors, we’re so happy with them and the guys were quick, responsive and all around brilliant. Would really recommend Aspire Bifolds.
Libby R.
Libby R.
07:42 06 Sep 20
Very efficient and helpful service 2 years on from original door fitting.Thanks so much Aspire!
Kim L.
Kim L.
11:00 27 Jul 20
Aspire bifolds removed some old wooden sliding doors and replaced them with some lovely French doors. They did a fantastic job- they spent time with me to ensure I had made the right choice of door, it took no time to fit them and the fitter was friendly, polite, clean and courteous. Quote was competitive and I couldn’t recommend them enough!
Natasha H.
Natasha H.
19:59 23 Jul 20
We went with Aspire after getting a few quotes, they weren't the cheapest but were still competitive. We chose them on the basis of their reviews and I am really glad we did! The service has been excellent throughout, our doors were installed far quicker than we were expecting, the fitter's attention to detail is great, and the quality of the doors is fantastic.After installation we did have a few problems with finding marks on the glass, which is provided by another firm, and had a few panes replaced. John, the director, ended up coming round himself and offered to replace the final pane. I know that many firms would just have ignored our calls once we had paid everything, so to have this level of service was fantastic. This proved our decision to go with a slightly more expensive firm in Aspire was the right move!
Scott S
Scott S
12:10 16 Jul 20
After a lot of research I came across Aspire Bifolds, went to the showroom and they have a very good selection of doors to choose from.From start to finish it's been a pleasure to deal with everyone connected to Aspire Bifolds and their aftercare service is first class.Top quality product, installation and all round experience from this company. Would have no hesitation in using them again.
Paresh M.
Paresh M.
12:32 14 Apr 20
Professional first class service from start to finish. Highly recommend on service and price
Catherine Kenton M.
Catherine Kenton M.
18:59 08 Apr 20
We recently used Aspire for purchase and installation of smart system heritage doors for our extension. We are thrilled with the finished product. John and the team are brilliant, every person I spoke to was helpful and friendly. Email response was really fast. The whole process from start to finish was seamless and stress free.The installers were efficient and tidy, they left the place cleaner than when they arrived. Following installation we noticed a scratch on one of the panes, we thought it could be buffed out, but the whole pane was replaced without issue within a week.It is rare to find a company with such great customer service and work ethic these days. I would certainly be happy recommending Aspire to anyone.
Rebecca D.
Rebecca D.
11:39 27 Feb 20
I visited Aspire Bifolds to discuss some technical details of the installation requirement for sliding doors. Both of the staff I dealt with were friendly and helpful and in particular Ji was able to answer all of my questions and demonstrate some of the details on the door installation in the showroom. Overall a very helpful visit.
GeoffandLesley H.
GeoffandLesley H.
23:47 22 Feb 20