The Buyers Guide to Bi-Fold Doors

Does the prospect of sliding open an entire wall of your house to the outside excite you?

Is your imagination fired by all the possibilities that come with a connected outdoor indoor space?

Do you long for a wow factor for your home?

Then, like us, you’ll be enraptured with thoughts of bi-folding doors.

bi-fold doors shown in opening sequence


Before we all get carried away, there are a few things, practical things, to consider to make sure that bi-folds will be right for us and that we buy the right bi-fold doors.

Undoubtedly there will be some questions that we, or at least our other half’s will have, so lets tackle the most common one’s. So we can be ready when they ask…

Are Bi-fold’s right for my home?

We ask ourselves will the room naturally extend into the immediate outside space so that it flows off the interior?

This generally works best when the outside area is on or can be made to be at the same level. It could be a patio with seating area and garden. A walled courtyard that becomes part of the house. It is sometimes a pool area or stunning vista.

Whichever it is, will opening it up feel like we have just extended the room?

It is generally a sunny spot at the time we will want to use it. Perhaps it will be a kitchen/breakfast area where we can enjoy the morning sun. Or afternoon/evening entertaining space. Or the way to connect our home with the delights of our garden.


Bi-fold doors opening onto garden at Haworth in Yorkshire


Imagine ourselves opening up the new Bi-fold doors, when it’s right it’s what we call our Nina Simone moment, as more than likely we will want to sing:

“It’s a new dawn, it’s a new day, it’s a new life for me and I’m feeling good!”

Of course it is possible, hard to believe I know, that Nina wasn’t singing about bi-fold doors.


What if the room we want to open up is at the corner of the property? What if the ideal outside space wraps around the corner? This might seem like a problem, but actually bi-folds might well be perfect.

corner opening bi-fold doors


As long as suitable structural support is in place, bi-folds can extend such as to fully open up the corner. This makes a dramatic difference to the feel of the space, as, in effect, two walls have been drawn back.

What style is right for my home?

Traditional home, traditional timber frame doors. Modern home, sleek modern aluminium frames. That would be a standard approach, however, don’t rule out the dramatic effect that contrast can play.

Note restrictions may apply in conservation areas and on listed buildings.

Thick profile PVC frames lend themselves to 'chunkier' design. Thin profile aluminium frames provide a multitude of design options to suit Victorian; Edwardian; and Georgian period homes as well as contemporary new build properties.

Consider the amount of light that larger or smaller glazing will introduce into the home. Full height and width glazing gives big views drawing in lots of light. A more traditional design may marry with a home’s character.

Sashes can fold internally or externally, so consider which would make most sense for the opening. Choose to place the opening at the side so the sashes all fold one way to one end, which creates a single entrance door for easy access. Or choose a middle opening to give the option of a double door.


External outward opening bi-fold doors


Internal inward opening bi-fold doors

What about creating an opening?

Removing brickwork to be replaced with bi-fold doors is not difficult, however it obviously needs expertise (usually your builder) to ensure that you maintain the structural integrity of your home.

Top hung doors need a strong lintel to bear the weight. Bottom rolling doors are supported at the foot where a damp-proof course membrane is laid.

Take the opportunity while creating the opening to allow for the frame to be sunk into the floor to create that ideal low threshold and seamless transition from indoor to out. Any low threshold opening needs to be fully weather sealed.

Will I be warm in winter?

Look for glazing with a U value of 1.8W/m²K or lower. For more energy savings consider triple glazing.

Will I be secure?

Look for secure deadlocks which only need a single key and can be opened from inside or outside.

Intermediate panels should have a locking system that stops the panels from being lifted off the tracks. The runners that attach the doors to the top of the frame should also prevent panels being lifted out of the frame.

Intermediate shoot locks can be added to the door panels. They do not have to be used daily but if you are going away they can easily be locked for additional security.

What upkeep do they need?

Timber does require regular painting to keep the wood sound. Aluminium requires virtually no upkeep.

Will bi-folds add value to my property?

Bi-fold doors are very desirable, although not necessarily adding value, make a house very saleable.

Some of the worlds best homes use bi-fold doors as a dramatic feature, folding back entire walls of glass to give them a real wow factor which you can emulate in your own home.

bi-fold doors for the best unobstructed views

“I’m feeling good!”

Find out about quality bi-fold doors from Marlin Windows here