Optio BSF70 HI Bifold Door

Aluminium bifold doors in kitchen

Expand your living space by opening wide expanses of your external walls to your outside space

Enhance your design with our best-loved bifold door. Many thousands of discerning customers across the UK have selected the BSF70 HI bifold door system, enjoying the panoramic view and the unrivalled performance it delivers.


Multiple panels can be added to accommodate the unique design specifications of the house, with the option to open-in or out as required. The system’s narrow profiles ensures that maximum glazing is achieved, flooding spaces with natural light.

With a floating mullion frame, the BSF70 HI bifold door can be opened up completely on two sides to enjoy uninterrupted views of your outside space.

The innovative, flush line pop-out handle allows panels to stack flush when they are fully open, adding to the sense of openness that can be achieved.


  • Maximum control over the style of the doors
  • Maximum glazing could be achieved
  • Innovative flush line pop-out handle – allows panels to stack flush when fully open
  • High level of safety and security


  • Internally beaded with a softline or square detail to all external doors and panels 
  • Four stainless steel wheels ensure smooth and consistent operation
  • Unique, flush line pop-out handle that allows maximum door opening and square stacking of panels
  • Tested to PAS 24 and certified under the Secured By Design scheme


  • Heavy-duty roller options
  • Chamfered and square bead options
  • Low threshold option that can be configured to achieve DDA and Part M compliance
  • Doors and panels can be used in a variety of configurations, style and design
  • All configurations are available in both open-in and open-out options -Full range of bespoke hardware available
  • Glazing sizing range of 24mm–40mm
  • Available in single or dual colour polyester powder coating, texture and anodised finishes


In addition to the inherent strength of aluminium, the BSF70 HI combines security hinges and locking mechanisms with a unique heavy-duty roller design to provide the security and reliability demanded in high traffic applications. The system also incorporates a pop out T-handle design that allows for square flush stacking panels when doors are fully open.

The BSF70 HI offers superb air, water and wind resistance, with exceptional test results, which gives you peace of mind that this durable door can withstand the extremes of British weather.

Security is assured with full PAS 24 security accreditation, which also ensures that the BSF70 HI can be fitted in new build projects which require compliance with Part L.

With U-values of 1.4 double and 1.1 triple, this door is an energy-efficient option for both new build and refurbishment projects.

Standard Technical Data HI technical data
U value W/m²K 1.4-1.6 W/m²K 1.1-1.4 W/m²K
Air tightness (Pa) Class 4 (600 Pa) Class 4 (600 Pa)
Water tightness (Pa) Class 9A (600 Pa) Class 9A (600 Pa)
Wind load (Pa) Class E (2400 Pa) Class E (2400 Pa)

A more sociable space

“Opening out, the BSF70 panes are tucked away when they are open and give me a much bigger, more sociable space to entertain and relax. I looked at other options, but the bi-fold made perfect use of the space and gave me the contemporary look and feel I wanted.”

Jayne - April 04, 2021

The WOW factor!

“As property developers, we have worked with MGP Windows on many occasions in the past and knew that their AluK doors would be our first choice for this project. The finished result is stunning and has given the property yet more wow factor.”

Pool house homeowners - October 26, 2020