Bifolding Door Glossary of Terms

This bifolding door glossary explaines the many different elements and parts found in our bifolding range covering several brands. If you are currently researching buying new bifolding doors for your home, your local home improvement company may use terminology to explain bifolding doors and their installation you may not be familiar with.

We have put together this glossary of the most common bifolding door terms to help you.

Picture of black bifold doors supporting a bifolding door glossary of terms

Bifolding door configuration.

The bifolding door configuration is the design of your bifolding door including the number of door panels and how they open, slide and fold.

Bifolding door sight lines.

Sight lines refer to the visible aluminium profile, mainly when the doors are in the closed position. Sight lines on bifolding doors vary according to the system.

Bifolding door outer frame.

The bifolding door outer frame is the perimeter frame fixed to the structure of the property. The outer frame carries the gearing that makes the bifolding door slide, fold and lock. Outer frames can also contain the seals that keep your door weather resistant.

Bifolding door jambs.

Bifolding door jambs are the sides of your door outer frame. Some systems offer adjustable jambs that the installer moves into position to ensure consistent door clearances throughout the bifolding door assembly. The lock jamb is on the locking side of the door and contains the keeps that the multi-point locking on the bifolding door engages into.

Bifolding door cill and threshold.

The bifolding door threshold is at the base of your bifolding doors. The rollers sit within the threshold enabling the doors to slide. Beneath the threshold is the cill (also sometimes spelt sill). The requirement for a cill depends on the way the bifolding door is being fitted and the individual property.

Polyester powder coating.

Polyester powder coating is the paint finish applied to bifolding doors. Polyester powder coating is a dry paint process. An electrical charge is applied to the aluminium sections and the coloured powder bonds to the aluminium. The aluminium sections are then placed in a special oven to cure the powder and create the final colour. A bifolding door is available in over 150 different colours.

Bifolding door seals.

The seals on a bifolding door are available in EPDM Rubber or a Q-Lon material. You will find bifolding door seals on the outer frame and the door sashes. When the doors close together and meet the frame, the seals compress to provide weather resistance and protection from the ingress of water or rain.

Thermal break.

A modern aluminium bifolding door has a thermal break. This is a polyamide strip to separate the inside and outer frames of the aluminium extrusion. Thermal breaks insulate the aluminium profile and help with the overall energy efficiency of the bifolding door. The thermal break can be painted white or left naturally black. The thermal break is only visible when the doors are open in the same way the locks, hinges and other components are visible.

Bifolding door leaves.

The bifolding door leaves are the door sashes that slide and fold. Depending upon the configuration, bifolding door sashes contain the traffic door and the intermediate or slave door panels.

Traffic Door.

The traffic door is an independent door that operates just like a regular swing door. A traffic door is most useful in a bifold for convenient access in and out without having to fold all the leaves back. Configure your bifolds with a traffic door if the bifolding door is the only external door in your home. Traffic doors are great for taking out the washing or rubbish and letting out pets quickly and easily.

Intermediate or slave door leaves.

In a door with a traffic door, the remaining doors are referred to as intermediate or slave door leaves.

Bifolding door carriage and top guide.

The bifolding door carriage is a component containing up to six wheels that enable the doors to slide within their track. The bifolding door carriage is found at the bottom of the doors in the threshold. The top guide is a similar component at the head of the doors designed to keep the doors in place as they slide.

Shoot bolts and gearbox.

The slave leaves on a bifolding lock with a handle fitted with a gearbox. The gearbox operates the shoot bolts that engage at the top and bottom of the door locking the door in place.

Bifolding door slave handle and D-Handle.

To pull the doors closed, the D-Handle is a round or square handle positioned above the slave handle. As you hold the D-Handle against the door, the slave handle is rotated to activate the shoot bolts.

You can view all these components and bifolding door glossary and terminology in our Letchworth showroom open Monday to Saturday. On display are many different bifolding door sets within real-world installations so you can see clearly how thresholds, frames, doors and sight lines can work in your home. At Open Living we also have a huge selection of colour swatches for aluminium and our range of integral or fabric blinds and door handles. Contact us today to find out more.

Published on May 21, 2017

Some of the images on our website are indicative images illustrating how products may look. Please contact us for full product details and specifications.
Aluco logo origin logo bereco logo fensa logo air logo which logo schuco logo

Customer Reviews

Ordered Origin bifold doors. Diane, Marsha and Danny have been a pleasure to deal with. Slight delay to install date but all handled professionally. Fitters completed in one day as agreed. The product is excellent, would thoroughly recommend.
David N
David N
10:44 25 Sep 21
Lovely aluminium French Doors.Initial issue with square of door sorted out immediately and the response from both the office and the fitter was excellent. I would fully recommend Open Living Ltd.
colin H.
colin H.
13:43 02 Feb 21
Excellent service designing, removing previous (tough job it was) and installing two bespoke floor to celing windows.
Richard J.
Richard J.
13:22 19 Jan 21
Open Living was one of the last suppliers we discovered, but we were taken by their great range of windows, doors and lanterns as well as their sales team. Diane walked us through the many options but also listened to our preferences. Rather than steering us toward the most expensive option they were usually able to offer a choice on each aspect and the pricing was very transparent and competitive. Excellent quality ranges of windows, doors and lanterns. We opted for the Origin bi-fold doors, Origin aluminium windows and Atlas roof lights, all superb build quality/spec and great colour options.The installation team led by Danny and backed up in the office by the all-knowing Marsha and Linda were efficient, thorough and a pleasure to have on-site, coordinating well with our builder. Our neighbours also used Open Living before us and had a few issues at installation, but we believe these were mainly due to a supplier issue. All our windows, doors and roof lights went in as planned, well secured and sealed, with no damage.The only little point of feedback on their whole process is that the final quote and specification can spread across more than one document which did add a little uncertainty. This meant we had to double-check exactly what was coming. An all-inclusive final statement of all the options would be good. However, with a little bit of checking everything did come exactly as expected and we are extremely happy with the finished project.We would definitely recommend Open Living.
Paul E.
Paul E.
11:21 29 Aug 20
Fantastic service, great customer care. 5****
Angela I.
Angela I.
08:40 02 Jul 20
Good staff ,great fitters excellent product!
Paulo R.
Paulo R.
17:45 07 Jun 20
Open Living installed Origin bi-folding doors for our home. Their quality and service has been excellent throughout. Very trustworthy company. Right from the start, they provided good advice to help us select the right doors for our home; their quote was very competitive; their customer service was excellent throughout as they kept us updated on progress. The quality of the doors and the installation has been top-notch. Would highly recommend.
Kinjal P.
Kinjal P.
11:06 05 Jun 20
Bought a bifold door for our house extension. Great quality products and fantastic service. Very happy with Open Living
Ajith S.
Ajith S.
14:37 21 May 20
We have just had are bifolding doors fitted,We're over the moon. Marsha is very helpful and friendly.Service was great 😀Would recommend open living.Geoff
Geoff P.
Geoff P.
10:01 18 May 20
Open living installed our ORIGIN bi-fold doors about a year ago now. The fitters were great guys with really good standards. We are so pleased with our installation. It’s great 👍
Phil B.
Phil B.
22:48 02 May 20
We purchased 1 set of bifold and 1 set of French patio doors, both Origin. Sales approach and customer service was excellent. Fitting and installation also excellent. Can't fault the product, either. Would have been 5 stars if it wasn't for an issue we had around the height of the threshold, which turned out to be much higher than we wanted/were expecting. This issue was resolved in a satisfactory way after discussion. Would definitely recommend, but my advice is to make sure the threshold height for patio doors is agreed at the survey and written on the paperwork before parting with any money.
Ashley B.
Ashley B.
07:52 10 Mar 20
Lovely people to do business with, we bought some BiFold doors and a window from OpenLiving. We did have a couple of minor teething issues once fitted but these were dealt with quickly and without fuss. Recommended!
Dino L.
Dino L.
14:03 28 Sep 19
I looked into a number of companies before deciding on Open Living in Letchworth for our bifold doors. I wanted the bifolds to be from a manufacturer that was very regarded, and Origin (though Open Living can also supply from Schuco and some other suppliers) certainly fall in that camp. I also liked the fact that Open Living were close to home, which made repeated visits to their showroom easy to make. Throughout the process, Linda and Marsha were professional and courteous and I would thoroughly recommend anyone who is looking to get bifolds to put OpenLiving Ltd on their shortlist.
Roy
Roy
16:16 04 Jul 19
So far I have ordered 12.5m sliding doors, 1 set of aluminium bi-folds and 5 windows from Open Living. The fitters are all great guys, and they take time to do a good job.The service and the products supplied have been excellent. I will be ordering more windows and do not hesitate to recommend them.
jeff H.
jeff H.
11:30 17 May 19
Had some OW80 windows that were fitted some time ago (by other installers, who had lost the cill caps).Marsha kindly helped me get some replacement items from Origin despite there being no financial incentive for open living to do so.Assistance has been very much appreciated and would highly recommend.
Mark I.
Mark I.
07:32 13 Mar 19
Great service and choice of products. Highly recommend Open Living
Allison M.
Allison M.
11:11 10 Dec 18
Great service from start to finish. The origin windows and doors look fab. Can highly recommend.
Emma G.
Emma G.
11:15 27 Nov 18
Great price on a roof lantern. Installed on schedule.
Niall R.
Niall R.
14:51 31 Oct 18
Great Service from start to finish. Communication was great. The fitting team were first classWw will recommend and use again in the future.
Asa H.
Asa H.
18:30 04 Sep 18
Superb all roundMarsha was polite and informativeThe system itself is sleek and works greatThe fitter I had was polite and very effective, clean and professionalAnd the price was not only reasonable but the cheapestI genuinely don’t know why you would opt for a more expensive system or company when the origin system provided by this company does it allSuper happy and will use on other properties I haveUse these guys, awesome3772.00 for 3 leaf fitted in a week!! Immense !LukeBishops Stortford
luke J.
luke J.
18:33 18 Aug 18
Great service and brilliant product. Really happy with how the house now looks. Couldn’t recommend them any higher.
Stuart C.
Stuart C.
18:06 23 Jun 18
Had a great experience with Open Living. We had a 6m run of Origin bi-fold doors, an Atlas sky light some upvc windows installed. Customer Service and communication was good throughout, the installation guys did a good job and their technical guy was helpful with determining levels so we could achieve a level and flush threshold on the door. On top of this they were by far the lowest priced installer we found for the Origin doors which we had quoted by another three suppliers. Would recommend to others and will use again.
Richard N.
Richard N.
20:02 22 Jun 18
Great customer service from start to finish. Very helpful and competitive price.Installation was fast and of good standard.Would highly recommend Open Living.
Noleen P.
Noleen P.
11:15 06 Jun 18
We weren't quite sure what bi-folding doors would be best but all the options were clearly and concisely laid out before us and some great solutions suggested to the issues we hadn't been able to work out on our own or with our builder. The showroom has lots of choice, brilliantly set out. We decided that Open Living would install our doors and they came and did a wonderful job.Looking forward to the spring to really get our new "open living" lifestyle underway!!
Paul S.
Paul S.
17:26 27 Feb 17
11 Amor Way Letchworth Point, Letchworth SG6 1UG
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