What is glass?
The Wood Guide · Materials
MaterialWhat is glass?
Sand, melted and cooled extremely quickly: a hard, clear material that absorbs no moisture. In furniture you mostly see it as a tabletop or cabinet door, often as toughened glass.
- Clear and moisture-resistant
- Toughened glass breaks into blunt granules
- Heavy and impossible to repair
Glass in brief
Glass is not a question of wood or no wood: it is an entirely different material. Hard, clear and indifferent to moisture, but also heavy and breakable.
Ordinary glass is made from sand, mixed with soda and lime, which is melted into a glowing liquid and then cools to a hard, transparent mass. It absorbs no water, does not deform in damp conditions and has no grain or knots. That is why it is so popular as a tabletop: it shows the base and makes a room look lighter.
In furniture it is usually toughened glass, also called safety glass. This is glass that, after being cut, is heated once more and then cooled quickly. The result is considerably stronger than ordinary window glass, and if it does break, it falls apart into small, blunt granules instead of large sharp shards.
A toughened glass top can take a firm knock, but not everything. The edges and corners in particular are the sensitive spots. And when toughened glass breaks, the whole top goes at once: you cannot repair a toughened top, you replace it.
- What
- melted sand, soda and lime, cooled to a hard, clear mass
- Moisture
- absorbs no water and does not swell
- Surface
- smooth and transparent, no grain
- Toughened
- stronger than ordinary glass; breaks into blunt granules
- Weight
- heavy for its thickness
- Repairing
- not possible; you replace a damaged top
- In furniture
- tabletops, cabinet doors, shelves
To be honest, glass is heavy and breakable. A glass tabletop shows dust and fingerprints more quickly than wood, and a scratch or a broken corner cannot be touched up the way it can on solid wood, where you can sand.
Ordinary glass and toughened glass side by side
The difference lies not in the raw material but in the treatment. For a piece of furniture, that difference is the most important thing to remember.
| Property | Ordinary glass | Toughened glass |
|---|---|---|
| Strength | breaks relatively easily under a knock or bending | considerably stronger at the same thickness |
| When it breaks | large, sharp shards | small, blunt granules |
| Cutting or drilling | still possible, by the glazier | not possible after toughening; everything must be made to size beforehand |
| Temperature differences | more prone to cracking | copes with them better, but putting a hot pan directly on the top is still not advisable |
| Edges and corners | vulnerable | remain the weak spot: avoid knocking the edge |
| Moisture | no problem at all | no problem at all |
How toughened glass is made
- MeltingSand, soda and lime are melted together into a glowing liquid.
- Forming a sheetThe molten glass is drawn into a flat sheet and cooled in a controlled way. This gives you ordinary, clear flat glass.
- Cutting to size and processingThe sheet is cut to size. Edges are finished and any holes for fittings or hinges are drilled now, because that is no longer possible afterwards.
- Heating againThe glass sheet goes into a furnace and is heated to a high temperature, well above 600 degrees.
- Cooling extremely quicklyNozzles then blow cold air against it, so that the outside cools much faster than the inside. As a result, the outer layers are under compression and the core under tension.
- Ready for useThat built-in tension makes the top stronger. But it also makes it impossible to repair: if it breaks, the whole sheet falls apart into small granules.
Besides toughened glass there is also laminated glass: two glass sheets with a film between them. If it breaks, the pieces stay stuck to the film. You often see it in car windows and glass balustrades. When this article says "toughened glass", it means the first type.
Glass in furniture and in our range
Tabletops
Coffee tables, side tables and dining tables with a glass top. The base stays visible, which makes the piece look lighter.
Cabinet doors and display cabinets
Glass doors let you see what is in a cabinet without opening them.
Shelves
Glass shelves in racks and display cabinets let light through.
Mirrors
A mirror is glass with a reflective layer on the back.
Glass in our furniture
With us you find glass in two pieces of furniture, among others. On the coffee table it is a toughened glass top, resting on six metal supports according to the product page. On the TV unit it is the two glass doors; we do not state which type of glass that is there, so we make no claims about it.
On the coffee table, the base is made of MDF with an oak decor. You can read more about that board material on the MDF page, and about engineered wood in general on that page.
Glass or wood as a tabletop?
You do not choose one or the other because it is "better". You choose based on what you expect from your furniture.
Light in appearance, sleek
The choice if you want a piece of furniture that makes the room look more spacious and has little to fear from moisture or stains.
- Absorbs no liquid; spilled coffee simply wipes away
- Keeps the view of the base clear
- No grain, no knots, no oils or lacquer to keep up
- Shows dust and fingerprints readily
- A damaged top cannot be touched up
- Heavy and breakable if the edge is knocked
Warm and repairable
The choice if you want a piece of furniture that lasts a very long time and is allowed to age.
- Feels warm and has character
- Scratches and dents can be sanded out or touched up
- Does not fall apart all at once
- Keeps stains and moisture out less well
- Needs upkeep, depending on the finish and the type of wood
- Changes in colour and appearance over time
For a coffee table in the living room, a glass top is an excellent choice: you put a cup of coffee on it and wipe it clean. For a table that gets heavy use, that children climb on, or that stands outdoors, you are better off with solid wood or a sturdy board material. Our glass furniture is indoor furniture.
Care and safe use
Cleaning
An ordinary glass cleaner and a microfibre cloth are enough. That is also what we recommend for our coffee table.
Heat
Do not put a hot pan or dish directly on the top, not even on toughened glass. Use coasters or trivets.
Edges and corners
Those are the vulnerable spots. Do not let hard objects hit them, and do not lift a glass top by one side only.
Scratches
Do not slide rough or sharp objects across the top. Glass is hard, but not scratch-proof.
Keep indoors
A glass top can withstand moisture itself, but our glass furniture is indoor furniture: the MDF base is not for outdoor use.
Crack or broken corner
Do not keep using a cracked or chipped top: replace it, because a damaged top can break unexpectedly.
Frequently asked questions about glass
What is the difference between toughened glass and ordinary glass?
Toughened glass is heated once more after cutting and then cooled extremely quickly. That makes it considerably stronger than ordinary glass, and when it breaks it falls apart into small, blunt granules instead of large sharp shards. A toughened top can no longer be cut or drilled afterwards.
Can I remove a scratch from a glass tabletop?
Not really. Unlike wood, you cannot sand glass. A damaged toughened top is usually replaced. So use coasters and do not slide rough objects across the top.
Can I put a hot pan on a glass table?
Preferably not, not even on toughened glass. Toughened glass copes with temperature differences better than ordinary glass, but putting a hot pan directly on the top is still not advisable. Use trivets.
Why does toughened glass break into granules?
Because of the treatment, there is tension in the glass: the outside is under compression, the core under tension. When the top breaks, that tension is released all at once and it falls apart into many small pieces. These are blunt, which makes it safer than shards.
Is glass suitable for outdoors?
Glass itself is not affected by moisture, but whether a piece of furniture can go outdoors depends on the whole piece. Our furniture with glass is indoor furniture: the base is not weatherproof.
Which furniture with glass do you have?
A coffee table with a toughened glass top and four pouffes, and a TV unit with glass doors. All the details are on the product pages, indicated above.
Choosing a coffee table
Glass is one of the ways to make a coffee table. Also take a look at the coffee tables in wood and read how MDF, the material under the glass, is made.
Have a question about your project? Just ask — we're happy to help.