Why choose Liniar ModLok™ bi-folding doors?

Queen's Awards for Enterprise- Innovation 2017 EmblemLiniar’s ModLok™ bi-folding doors offer a totally unique option, thanks to the patented exoskeleton design giving them unparalleled strength, security and durability. No other PVCu bi-folding door has been tested to over 127,000 full opening cycles; and with low U-values, PAS:24 and Secured By Design accreditation, the Liniar ModLok™ is in a class of its own – earning the accolade of a Queen’s Award for Enterprise in Innovation in 2017.

Ideal for large openings, ModLok™ bi-folds enable you to open up an entire wall of your room – creating space and letting fresh air and natural daylight flood into your home.

Stunning alternative

Whether you have a bedroom with Juliette balcony, a kitchen-diner, a conservatory or an orangery, Liniar ModLok™ bi-folding doors can provide a stunning alternative to patio or French doors. Available in wide choice of opening configurations and colours, the Liniar ModLok™ bi-fold has ultra-slim sightlines, providing rooms with a clean, modern appearance.

Safety features include the innovative low threshold option for family friendly and wheelchair use. What’s more, Liniar bi-fold doors offer high energy efficiency, combined with the best security features on the market – bringing you a modern space-saving solution for your home that will definitely give it the ‘wow’ factor.

Find out about the range of thresholds available. 

Better for the environment

One of the most effective ways you can save energy within your home is through installing energy efficient windows, doors and roofs. Liniar frames outperform the majority of other leading brands in the UK when it comes to thermal efficiency – mainly due to our innovative uPVC multi-chambered profile design.

The thermal efficiency of a door is measured in U-values, which demonstrate how effective the door is at preventing the transfer of heat into and out of a building. The lower the U-value, the higher the doors’ effectiveness at keeping the heat inside your home when it’s cold outside.

For greater thermal efficiency, the Liniar ModLok™ bi-folding range can be fitted with triple glazing, reaching an impressive U-value of 1.0 W/m²K, which means you’ll be able to enjoy a warmer and quieter home as well as lower energy bills.

A grand design

Bi-folding doors are becoming more popular than ever before, thanks in part to their regular appearance in television home make-over and lifestyle programmes.

Timber and aluminium are often perceived as the only materials that can be used for bi-folding doors, but doors made from lead-free uPVC can actually offer many benefits:

  • Smoother operation
  • Higher thermal efficiency
  • Low maintenance
  • Exact matching with your other doors and windows

Superior efficiency

With Liniar’s foiled woodgrain-effect options, your bi-folding doors can emulate the natural look of timber and you will never have to treat, sand or repaint them. If you choose our flat grey frames, your bi-folding doors will rival any comparable aluminium range on the market, offering superior energy efficiency at a more cost effective price.

And Liniar’s ‘top of the range’ ModLok™ bi-fold doors offer even greater strength and rigidity, combining all of the structural benefits of an aluminium door set with the energy efficiency of uPVC.

All Liniar bi-folding doors are ‘bottom rolling’, not top-hung – meaning no extra stresses are placed on your building’s lintel.

Discover for yourself why more and more people are choosing Liniar’s bi-fold doors and benefiting from these versatile and attractive home improvements – and find out more about ModLok™ technology here.

Click here to see our video showing the correct method for opening and closing a Liniar bi-folding door.

Find your nearest Liniar fabricator here or contact us for more information.

Mark II loves Liniar ModLok™ Bi-fold Doors!

“Our ‘top of the range’ ModLok™ bi-fold doors offer even greater strength and rigidity, combining all of the structural benefits of an aluminium door set with the energy efficiency of uPVC.”

Hi, I'm Mark II
Head of Testing at Liniar

Explore our ModLok™ Bi-Fold Doors

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Choose your colour

  • Sculptured
  • Chamfered


Why choose Liniar?

Minimal Maintenance

Low maintenance

You can rest assured that you won’t need to spend hours looking after your set of Liniar bi-fold doors to maintain their beauty.

Unlike timber, you won’t need to treat or paint them each year to keep them in top condition – and that’s not all; our 10 year frame guarantee gives you the peace of mind that the colours won’t fade.

All that is needed to keep them looking their best is an occasional quick wash with soapy water.

Family friendly

The Registered Design protected Liniar low-threshold option provides a seamless point of entrance and exit, making it perfect for family homes.

An optional tray to seat the low threshold creates an easy-access ramp for wheelchairs and prams without the need for messy and expensive excavation.

Ultra-low, the Liniar threshold measures just 24mm at its highest point, with silver or gold finish options to perfectly complement the door hardware.


Slim hinges with internal hidden fixings, not only maintain the sleek lines but enhance security as they can’t be unscrewed from outside.

We wanted to offer a low threshold, without the need for expensive and messy excavation, so we designed our own clever solution.

We’ve even designed folding keys, to avoid any problems with keys being left in the locks during operation – it’s often the small things that make a huge difference.

Open up your business

Not just for the family home, Liniar bi-fold doors can bring a whole new dimension to your commercial or business property.

Maximise floor space at your pavement café by opening up an entire wall in the summer months, while knowing your energy efficient Liniar bi-fold doors will also keep in the heat during the winter.

Give your showroom a new lease of life by installing Liniar bi-fold doors for ease of access, together with the highest possible security.

Less Frame, More Glass

Less frame, more glass

Liniar ModLok™ bi-fold doors have ultra-slim sightlines, providing rooms with a modern, clean appearance - letting in the maximum amount of natural light.


Featuring patented ModLok™, a combined aluminium reinforcement and multi-point locking system, provides an unrivalled appearance with a high security locking mechanism.

Door Configurations


Liniar ModLok™ Bi-fold doors are available in a range of opening configurations from 2 to 7 panes so they can be truly tailored to your requirements.

Fully Tested Products


Along with security and weather testing, our ModLok™ bi-fold door has been tested by our in-house robot to over 120,000 opening sequences - 10 times the British Standard.



The Liniar ModLok™ Bi-fold is packed full of innovative features, concealed hardware to folding keys making it the first true alternative to aluminium bi-folds.

Customer choice

Liniar ModLok™ Bi-fold doors are available with a range of additional options, from handles and hinges, to low and half thresholds.

Strong and secure

The shootbolt locking mechanism designed into each Liniar bi-fold door ensures the door is bolted firmly into the stainless steel track, maximising your security. Built-in anti-lift features, anti-bump cylinders and optional anti-snap cylinders combine to bring you extra security.

Liniar’s bi-fold door range is also available with ModLok™, a new concept in locking technology. ModLok™ is a highly innovative combined reinforcing and locking mechanism, bringing additional strength and rigidity to the doors and enabling you to have even wider configurations of bi-folding doors.

Super smooth action

Smooth Roller

Liniar bi-fold doors are specifically engineered so that they won’t bend or warp – while the super smooth rolling action gives them an incredibly light feel.

Ergonomic handles are built in to each hinged section, making the doors easy and safe to operate for any user, young or old.

Liniar’s patented roller mechanism is hidden within each door, maintaining its sleek lines and giving all Liniar doors the most effortless glide action available in the marketplace.

Discreet magnets ensure that when the doors are folded back they will remain in place.