Tree in a field on a sunny day

How to Recycle Window Glass

Glass recycling isn’t exactly a new idea. Hopefully you will have been using your local bottle banks for many years now, and recycling all your sauce jars and bottles wherever and whenever you can. But this isn’t the only sort of glass that can be recycled: the stuff in your window is just as amenable to being melted down, reformed, and ultimately reused.

Can You Recycle Window Glass?

There are a few differences between the glass in your windows and the glass that makes bottles. Window glass is treated using a special combination of heat and chemicals. This makes it more difficult to break, and also gives it a higher melting point. Moreover, when it does melt, those chemicals leak out – which if you’re creating new glass products designed for food and drink storage, is a considerable problem.

The long and short of all of this is that window glass can’t be mixed with general glass recycling. It can be either used to make more windows, or it can be ground into a powder and then used as a bulking agent in cement and concrete. This means putting in a special recycling bin. In the developing world, this requires infrastructure which simply isn’t yet in place. In the UK and Europe, however, the story is a little different. A Europe-wide project is currently underway, which aims to make the recycling of this sort of glass economically viable, and thereby spread the practice.

Recycling Glass Windows

So, you might be asking, how do I get rid of old windows? You have several options available, but the most straightforward is locate your nearest recycling centre and make a trip down there.

Where Can You Recycle Glass Windows?

The chances are good that you’ve a suitable glass-recycling facility within a few miles of where you’re now sitting. British Glass provide a useful tool which will help you to locate your nearest. Give them a call before you turn up, and check that they’ll take your window, and that they’re open to non-locals. You might find that you have other recyclable materials at home that can be disposed of on the same trip.

Re-using the glass

On the other hand, you might decide that you can re-use the glass elsewhere in your home. You might be able to extract the glass from your window and turn it into a cabinet, a tabletop, a picture frame, or even outdoor flooring. In the case of the latter, you’re going to be shattering the window into fragments, and leaving it to set on top of setting cement. When the whole thing is set, you can grind the thing down into a smooth, safe surface.

Obviously, this sort of thing is inherently dangerous, and requires that you take adequate precautions. Use protective goggles, gloves, and make sure that you sweep up any fragments or dust when you’re done.

Selling the Window

Of course, most of us will hesitate before going to all of this effort – particularly if we’re not all that creative. But you might find that someone else in your vicinity has a use for your old window, even if you don’t. Making a listing on a site like Gumtree or Facebook is free and may yield results. Perhaps someone needs a new window for their shed, or perhaps there’s a local artist who specialises in glass!

timber sash window

How Many Windows Are There in the World?

Over the course of any given day, we’re asked all manner of questions about windows. Some of them come up frequently, and have straightforward answers which we’ve written about on these very pages. But there are other, more difficult window-related questions which can be a little bit trickier.

Candidates in job interviews are sometimes attacked with the age-old ‘how many windows are there in a given area’ question. It’s designed to test your ability to think logically under pressure. It’s also pretty unfair. But we’re not going to leave high-flying job applicants squirming; we’re experts on all things window-related, and so we’ll try to shed some light on the matter.

What do we need to know to work out how many windows there are in the world?

It’s impossible, of course, to give a precise answer to this question. But we can do a little arithmetic based on a few carefully-considered assumptions, and come up with a serviceable estimate.

One factor we have a decent knowledge of is the number of people in the world. We can put this at around 7.7 billion, but for the sake of easy maths we can call it eight. Now all we need to work out is how many windows there are per person, and we’re set.

But we’ve just kicked the can down the road, here, because we’re no way of knowing how many windows there are per person. If you’re living in some parts of the developing world, your house might have just a single window shared between a dozen people. If we say that the average family has four members (ranging from one-person households to those with thirty or more), that means 2 billion households. We might say that the average house has around ten windows, which puts us at twenty billion. Plug in a few more accurate statistics and this figure may rise and fall dramatically, but it’s still a number.

Where things get really messy

Of course, this doesn’t account for government buildings, hotels, swimming pools, hospitals or offices. Nor does it account for the windows which haven’t yet been installed, and sit in factories, warehouses, and in showroom floors. Any what about the windows that have just been taken out and dumped in landfills?

And what about greenhouses? Do they count as one giant window, or several dozen small ones? For that matter, are we just talking about windows attached to buildings, or windows in general? Do car windows count? The average car has six of them – so if your household has two cars, you might have doubled the number of windows per household. And what about buses, trains, boats and aeroplanes, each of which can have hundreds of windows?

But not all glass panels count as windows. Obviously, a pair of eyeglasses should not count towards our estimate. But what about the sides of an aquarium? Is that a window, or is it just a big glass panel through which we look at fish?

Clearly, this is a problem just as much of definitions as it is of maths. So, the answer we’d suggest, if you’ve faced with this fiendish problem, is to say fifty billion. It’s not the right answer, but it is a plausible one. Of course, there may then come follow-up questions. But if you’re sure to mention all of the complicating factors that we’ve mentioned, you may look as though you’ve given the question at least a bit of thought. Besides, some interviewers might just be looking for an admission of ignorance: there is no good answer, and it might be worth fronting up and saying so!

Cleaning a wooden window

How to Clean Windows with Newspaper

Regular cleaning is essential if windows are to look their best. This will ensure not only that your view of the outside isn’t partially obscured by a thin veneer of grime, but that natural light can percolate through your interior to the greatest possible extent. There’s nothing more likely to liven up your living room than a healthy dose of natural light, courtesy of a set of clean glass windows!

One of the most popular ways of cleaning windows is with the help of old, scrunched up newspaper. This is among the most low-cost cleaning supplies, with many of us getting a paper through the door every week for absolutely nothing.

But what’s the best way to clean windows using old newspaper? Let’s take a look!

Using Newspaper to Clean Windows

As always, we’ll need to first assemble a few ingredients. In this case, there aren’t that many. You’ll need:

  • Newspaper (any will do)
  • Water
  • White vinegar
  • Washing-up liquid
  • A spray-bottle

For our purposes, we’re going to concoct a tried-and-tested home-brew cleaning solution. If you’d prefer, you can go out and buy one that’s been specially formulated (albeit at greater cost). But white vinegar is inexpensive and will break down all of the grime on your windows in moments, and thus it makes a fantastic solution for most circumstances.

First, we’re going to formulate our home cleaning solution. This can consist of a few drops of washing-up liquid, alongside a 1:3 mixture of white vinegar and water. You can experiment with the proportions for best results. Load it into a spray bottle and give it a vigorous shake before you get started.

Follow these steps to clean your windows effectively with newspaper:

  1. Apply the cleaning formula to the glass. It’s important to be cautious, here; vinegar has a habit of discolouring hardwood furniture and other surfaces, so we want to be sure that we only get it onto the glass. Apply in small patches at the middle of the window.
  2. Now, we can scrub the cleaner into the glass. Move in a small circle to begin with, so that the paper absorbs most of the cleaner. Then you can move onto larger vertical strokes from the top to the bottom of the window. Apply more cleaner as required.
  3. Using this method, clean every window as required, front and back. When you’re done, you should have a shining, transparent surface.

So, what makes newspaper so effective? Put simply, it’s rough enough to be very slightly abrasive. This makes it great at dislodging all of the tiny particles of dirt that, over the course of a week, will find their way onto the glass of your window, and it won’t leave fibres behind in the same way as toilet paper might. Of course, we might say the same about standard sheets of A4 – but newspaper is by far the more economical option!

bow window

What Was Used in Windows Before Glass Was Invented?

While the modern window might seem like a pretty simple contraption, it’s actually made from dozens of carefully-engineered parts. Double-glazed windows are able to insulate far better than a single sheet of glass – but even that required hundreds of years of refinement and engineering before it could be made thick and flat enough to actually see through.

Before the earliest forms of glass came to be, a window would be a simple hole in the side of a building, over which could be hung crude animal-skin curtains at night-time. Not terribly comfortable! So how did the modern glass window come about?

When Were Glass Windows Invented?

Glass, as a material, is rare in nature. Usually, it comes in the form of obsidian – which is entirely black. Synthetic glass first came to be widespread in ancient Egypt and Mesopotamia in around 3500 BCE, and came to be used for vases and cups thousands of years after that.

Glass windows, on the other hand, came much later. The ancient Romans used them, sporadically, in the more upmarket villas and government buildings – though their optical qualities were far behind what we might expect today. In certain places, like churches, this difficulty became an opportunity: stained glass windows allowed for the depiction of certain religious scenes. In this setting, transparency didn’t matter.

The earliest forms of window glass were ‘broad sheet’. These were made by first blowing a tube of glass, and then cutting off one side and rolling the whole thing flat.

The difficulty of manufacturing glass windows made them something of a status symbol – and this continued right up to Tudor England, where only the wealthiest households could afford windows of a decent size. In Europe, the Italian renaissance left no aspect of culture or industry untouched. Windows there became taller and sleeker, and separated by mullions and transoms (the wooden crossbeams which run across the surface of a window). As time went by, these elements were made progressively narrower – so that more light could pass through the window.

The Sash Window

The 17th century saw the introduction of an entirely different sort of window: the sash window. This variety of window consisted of two moving panels, which could slide behind one another to create an opening. Windows of this sort needed to be made from ‘crown glass’: a more affordable material created by spinning discs of the stuff, and then cutting those discs into broad sheets.

Modern Windows

Today, our windows are almost universally made from machined ‘float’ glass. This process came about in the mid 19th century, and though it’s been extensively refined since then, the principles used today remain the same: the molten glass is poured into a bath of molten tin. The two materials are immiscible, meaning the sheet floats upon the molten tin as it cools (like oil might float on water). The result is a perfectly smooth sheet on both surfaces, which, after a little bit of extra treatment, becomes perfectly transparent.