We supply and fit made-to-measure bifold doors in Fortis Green, in aluminium and uPVC. This page is for homeowners in Fortis Green who want to open a kitchen, extension or garden room onto the outside. You will find the main choices, what the work involves on local homes, what drives the cost and how to look after the doors once they are in.
Every set is built to your opening and fitted by our own team. We are FENSA registered, and each install comes with a 10-year guarantee. For the full range of styles and hardware, see our main bifold doors page. For other work in the area, go to our Fortis Green glazing page.
Bifold doors in Fortis Green: local notes
Most of our bifold work here is at the back of the house, where gardens are close to the kitchen. Access and parking shape how we plan each fitting day.
- Streets we often work on: Twyford Avenue, Eastern Road and Western Road
- Close to: Coldfall Wood
Building control for this area is handled by Barnet Council. If your opening needs a new beam, we will tell you at the survey and explain who deals with sign-off.
Aluminium or uPVC Bifold Doors?
Both work well. The right one depends on the size of the opening, the look you want and your budget.
Aluminium is the strong choice for wide openings. The frames are stiff, so the panels stay true over a long run. That means slim sightlines and more glass. Good systems use a thermal break inside the frame, so the cold outside does not track through to the room. Powder-coated finishes come in a wide range of colours, and you can choose a different colour inside and out.
uPVC suits smaller openings, such as a three-panel set in place of old patio doors. The frames are deeper, so you see less glass, but they hold heat well. Steel inside the frame keeps the panels from dropping over time. uPVC is often the better fit when the opening is modest and cost matters most.
On both, the glass and the fitting count as much as the frame. A well-fitted uPVC set will beat a badly fitted aluminium one. We fit sealed units with low-E glass, argon gas and warm-edge spacer bars as standard.
How Bifolds Suit Fortis Green Homes
We look at the house first, then the doors. A few points come up again and again on local jobs.
- Rear extensions. A new single-storey extension is the most common place for a wide bifold set. We can work from your builder's drawings and agree the opening size before the steel goes in.
- Old patio doors. Many homes still have sliding patio doors from decades ago. A bifold set can often go into the same opening with little building work.
- Back-to-front access. On terraced homes, the doors may need to come through the house. We plan panel sizes and delivery so nothing is too large to carry in.
- Garden levels. If the patio sits higher or lower than the floor, we plan the threshold and drainage so rain stays outside.
Some streets in Fortis Green sit in or near conservation areas. Bifolds at the back of a house rarely need planning consent, but rules differ for listed homes and flats. We will flag anything that needs a check with the council before you order.
Panel Layouts and Sightlines
The number of panels shapes how the doors look and how you use them. We start by measuring the clear opening. Then we agree how many panels will span it.
- Panel count. Fewer, wider panels mean more glass and fewer frame lines. More, narrower panels stack in a smaller space when the doors are open.
- Traffic door. One panel can open on its own, like a normal back door. This is the one you will use most days, so we size it to walk through with ease.
- Stacking side. Panels can fold to the left, the right or split both ways. Think about where the table, plants or a path sit outside.
- Open in or out. Most sets fold out, so the stack does not take up room inside. In tight gardens, folding in can make more sense.
Sightlines are the width of frame you see where two panels meet. Aluminium gives the slimmest lines. We show you sample sections so you can compare before you decide.
Thresholds, Glass and Security
A bifold set is only as good as the details at the floor and the locks. We cover these at the survey.
Thresholds. A low threshold gives a near-flush step from floor to patio. It needs good drainage outside to cope with heavy rain. A weathered threshold sits a little higher and keeps water out on exposed sites. We help you choose based on how your garden drains.
Glass. All glass in doors must be safety glass. We fit toughened glass as standard, and laminated glass where you want extra security or less noise. If you want better heat loss figures, ask about triple glazing for larger sets.
Security. Look for PAS 24 tested doors. Each panel locks with multi-point locks, and the hinges have anti-lift pins. The glass is beaded on the inside, so it cannot be removed from outside.
What Drives the Cost of Bifold Doors
We do not quote a set price on this page, because no two openings are the same. These are the main things that move the cost up or down:
- Width and height. Bigger openings need more panels, more glass and stronger hardware.
- Material. Aluminium costs more than uPVC, but gives slimmer frames and wider spans.
- Colour and finish. Standard colours cost less than special shades or a dual-colour finish.
- Glass choice. Laminated, solar-control or triple glazed units add to the cost.
- Building work. A new beam, a lowered floor or making good to brick adds labour.
- Access. Hard access, a narrow side path or limited parking can add time on the day.
After a free survey, we send a written, fixed quote that lists each item. Payment stages are set out in the quote, so you know where you stand. To book a survey, use our quote request form.
How the Job Runs
We survey, send your quote, make the doors to order and fit them, then leave you with your paperwork and guarantee. Each step is set out on our how we work page. Most bifold installs take one to two days on site. Larger sets with building work can take longer, and we will tell you this up front.
On the day, we protect floors, remove the old doors and fit the new frame level and square. We then hang the panels, set the rollers and check every lock. We clear our waste before we leave.
Looking After Your Bifolds
Bifolds need a little care to keep them running smoothly. A few simple habits will help:
- Vacuum grit out of the bottom track every few weeks, and after dry, windy days.
- Wash frames with warm soapy water. Do not use harsh or scratchy cleaners.
- Keep the drain holes in the threshold clear so water can escape.
- Put a light spray of silicone on hinges and rollers once or twice a year.
- Check the seals each spring for splits or flat spots.
If a panel starts to drag or the locks feel stiff, call us. Most problems are fixed with a small adjustment to the rollers or hinges.
Frequently Asked Questions
Can bifold doors be fitted on an uneven or sloping threshold?
Yes, but it takes a little more work. We use packers, an adjustable sill or a threshold adaptor to set the frame level. This keeps the rollers and hinges running well and the seals tight. On a steep slope, some small building work or a made-to-fit threshold piece may be needed. We check all of this at the survey, so there are no surprises.
Are bifold doors secure?
Yes, a good set is very secure when it is fitted well. Choose doors tested to PAS 24, with multi-point locks on each panel and anti-lift pins in the hinges. Internal beading stops the glass being taken out from outside. Laminated glass adds another layer. Keep the locks and hinges serviced, and use a FENSA registered installer so the work is signed off.
Can an old window or door be turned into a bifold opening?
Often, yes. A patio door opening can usually take a bifold set with little change. Making a window into a door, or widening a wall, means new steel or a new lintel. A structural engineer may need to size it, and building control will need to sign it off. We tell you what is needed at the survey and plan the work with your builder.
Do bifold doors need planning permission?
Swapping old doors for bifolds at the back of a house does not usually need planning permission. Listed homes, flats and some homes in conservation areas may need consent, so check with the council first. Building Regulations still apply for safety glass, heat loss and any new structure. As a FENSA member, we can self-certify the glazing work.
Which way should bifold doors fold?
Most people choose doors that fold outward, so the stack does not take up room inside. Fold-in doors suit small gardens or spots where the patio is tight. Think about where the table sits, which side you walk out on and where the sun falls. We go through these choices with you at the survey and show you how each option works.
Ready to talk about bifold doors in Fortis Green? We also work across East Finchley. Book your free survey and we will measure up, talk through the options and send you a written quote.