What Should You Consider When Choosing a Glass Balcony?

What is the difference between sliding and folding systems?

In a folding system the panels fold to one side and stack, so the balcony can be opened up almost entirely. In a sliding system the panels run on a track and pass in front of one another, so the opening stays partial depending on the number of panels.

If you want the balcony fully open in summer, folding has the advantage. If you will mostly use the space enclosed and open it only for ventilation, sliding is enough and easier to live with day to day.

What is the difference between insulated and standard glazing?

Standard single-glazed systems keep out wind, rain and dust. They protect the space to a degree but do not give the comfort of a room. In winter the area stays cooler than the rest of the home.

Insulated systems have a sealed gap between two panes, which reduces heat loss noticeably and makes the space usable as living area through the winter. In return the system is heavier and costs more.

The decision comes from one question, will you use this space as a sitting area in winter? If yes, insulated glazing makes sense. If not, a standard system does.

Will a glass balcony be cold in winter, and does it need heating?

A standard glass balcony creates an enclosed space but provides no insulation, so in winter it will be colder than the rest of the home. With insulated systems the difference is clear, though the space should still not be treated as the equal of a room.

If you are thinking of heating the balcony, say so before the system is chosen, because heating an uninsulated enclosure sends the energy straight outside.

Which installation details cause problems?

Three details cause most of the trouble, measurements not taken on site, drainage not planned, and the prevailing wind ignored.

Measuring must happen on site. Balcony openings are rarely standard, particularly in detached houses. A system produced to catalogue dimensions leaves gaps at installation, and those gaps show themselves with every rainfall.

Drainage is the second critical point, rainwater has to leave the bottom track rather than collect in it. On wind-exposed elevations, panel thickness and the locking mechanism should be chosen accordingly.

Is permission needed for a glass balcony?

This depends on the building and on local practice. In apartment blocks it changes the appearance of the facade, so a decision by the owners may be required, and in some cases the municipality may need to assess it as well.

The right approach is to consult your building management and your municipality before the work. On this subject trust your own municipality's current practice rather than general information found online, because it varies from district to district.

What glass is used in a glass balcony?

The glass used is toughened. Toughening strengthens the glass through heat treatment, and when it breaks it does not form sharp shards but small pieces with blunt edges. On a balcony, open to wind and to impact, that is the property that decides safety.

Thickness is usually chosen between 6 and 8 millimetres. As panel height increases and the elevation becomes more exposed, the thicker end is preferred. Panel size and thickness are assessed together, since looking at thickness alone is misleading.

In insulated systems two panes work together with the cavity between them providing the insulation. Total weight rises considerably, so the supporting profile and the fixing points are selected accordingly. Converting a standard system to insulated glazing later usually means changing the profile as well.

Where do the panels stack in a folding system?

In a folding system the panels do not disappear when opened, they stack at one end of the balcony. That stack takes up space, and where it goes is decided before installation.

The direction is chosen against where the view is and how the balcony is used. A layout that stacks the panels in front of the seating leaves the best corner of the balcony blocked whenever it is open.

Splitting the stack between both ends is also an option. Where there are many panels the depth of a single stack can become intrusive, and dividing it evens that out. This is decided when the measurements are taken, and changing it afterwards means rebuilding the track.

How do you choose on an exposed elevation?

Wind is the load a glass balcony system struggles with most. On the Aegean side the wind picking up in the afternoon can slam an open panel hard and tire the mechanism.

On exposed elevations the panel thickness is taken from the upper end, the supporting profile is strengthened and the locking mechanism needs to be a good one. The lock is there not only for security but to stop the panel being caught by the wind.

One detail is often overlooked, whether the panels can be secured in the open position. A system that holds its own position when open keeps the balcony usable on a windy day. It is worth asking about this at the measuring stage.

Why does condensation form on the glass?

Condensation is moist indoor air turning into droplets when it meets a cold pane. It is physics rather than a fault. In an enclosed and humid area with cold weather outside, water on the inside face of the glass is what you would expect.

Reducing it comes down to ventilation. If laundry is dried on the balcony the moisture entering the space rises sharply and the condensation follows. Short regular airing usually takes the problem below the level where it is noticeable.

In insulated systems the inner surface stays warmer and condensation drops. If you see misting between the panes, however, that is a different matter. It means the sealed unit has failed and that unit needs replacing.

Can an existing glass balcony be refurbished?

It can, and it is often more sensible than full replacement. Where the supporting profile is sound, the problem is usually in the moving parts.

The items most often replaced are the wheels and track, the seals and gaskets, and the locking mechanism. Panels that are stiff to slide, catch as they close or let rain in are usually down to one of those three.

If the profile itself has distorted, the fixings have worked loose, or the system was never sized properly for the balcony, refurbishment only postpones the problem. That distinction is made by looking at it in place, not from photographs.

How does the schedule work?

With a glass balcony the calendar starts at the measurement. From measuring to handover usually runs 3 to 5 days, and the installation itself is a small part of that.

Most of the time goes into manufacture. The panels are made to the dimensions of your balcony, so they do not arrive like an item picked off a shelf. The earlier the measurements are taken, the earlier the handover.

Clearing the balcony before installation day shortens the work. Planters, drying racks and stored items sitting along the line the profile has to follow mean the team moves them first.