You light the fire two or three evenings in a row and the glass is already grey, with a film of soot that hides the flames. Knowing how to clean fireplace glass doesn't call for expensive products: the most effective trick is to clean the fireplace glass with ash from the fireplace itself, and in about ten minutes it's usually clear again.
Contents:
- Before you start: three rules to avoid damaging it
- How to clean fireplace glass with ash
- Other homemade cleaners
- How to clean blackened fireplace glass
- Why it gets dirty and how to prevent it
- A simple routine for the whole season
- Frequently asked questions
Before you start: three rules to avoid damaging it
The glass in closed fireplaces, inserts and wood-burning stoves is usually ceramic glass: it withstands very high temperatures, but it scratches easily and should always be cleaned when cold.
- Wait until it's completely cold. On hot glass, water and cleaning products dry instantly and leave marks, and there's also the risk of burning yourself.
- No wire wool or abrasive powders. The scratches they leave collect even more soot afterwards.
- Protect the seal. The rope seal around the door keeps it airtight; don't soak it or rub cleaning products into it.
How to clean fireplace glass with ash, step by step
It works because wood ash contains alkaline salts that help dissolve the greasy soot, and its grain is so fine that it acts as a gentle polish.
- Take a little fine, pale ash from the top layer. Check that it's cold: it can hold embers for many hours after the fire has gone out.
- Dampen a ball of newspaper or kitchen roll with water, without making it drip, and dip it in the ash.
- Rub the inside of the glass in circular motions until the soot turns into a greyish paste.
- Wipe off the paste with another clean, damp ball of paper.
- Dry and buff with dry paper or a microfibre cloth.
If it's still dirty, repeat on the darkest areas.
Other homemade cleaners for the glass
If you don't have any ash to hand, these alternatives work too. Use them on cold glass and apply them to the cloth; never spray them near the seal.
| Method | Type of dirt | How to use it |
|---|---|---|
| Equal parts vinegar and water | Grey film and smoke marks | Damp cloth; dry thoroughly afterwards |
| Bicarbonate of soda and water paste | Stuck-on black stains | Leave for 10-15 minutes and wipe off with a damp cloth |
| Dedicated stove glass cleaner | Heavily ingrained dirt | Follow the instructions on the packaging |
If you use ammonia, always dilute it, keep the room ventilated and never mix it with bleach: together they give off toxic fumes. And for your windows, see our guide to cleaning windows without leaving streaks.
How to clean blackened fireplace glass
When the soot has hardened or turned brown from resin, you'll need a bit more patience:
- Remove the loose soot with dry paper.
- Spread a paste of bicarbonate of soda and a little water over the stains and leave it to work for 10 to 15 minutes.
- Rub with a cloth or the non-abrasive side of a sponge, without pressing too hard.
- Finish with the ash method and dry thoroughly.
If whitish marks or scratches remain after two goes, the glass may be damaged: contact the after-sales service for your fireplace before you carry on scrubbing.
Why fireplace glass gets dirty and how to prevent it
If it turns black after one or two evenings, the most likely reason is poor combustion. The most common causes:
- Damp wood. This is the main one. Freshly cut wood produces more smoke and less flame. The usual recommendation is less than 20% moisture, which you achieve by leaving the wood to dry under cover with good ventilation; dense woods such as holm oak or oak usually need more than a year.
- Air intake closed too far. A slow, smoky fire stains the glass in no time.
- Resinous woods. Pine and other conifers give off more resin; holm oak, oak or olive wood leave less dirt.
- Logs up against the door. If the wood touches the glass, the flame stains it directly.
If your fireplace has an airwash system, which creates a curtain of air over the glass, don't close its control completely.
A simple routine for the whole season
The trick to keeping the glass clean is not letting the soot build up: a quick wipe with ash every few fires takes a couple of minutes. For the rest of the house, take a look at our home collection. And if your dog or cat has claimed the spot in front of the fire, a reusable pet hair roller will help you get the hair off the blanket and the sofa.
Frequently asked questions
How often should you clean fireplace glass?
If you light the fire every day, a quick clean once a week is usually enough to stop the soot hardening.
Can you clean fireplace glass while it's hot?
It's not recommended. Besides the risk of burns, water or cleaning products on hot glass dry instantly, leave marks and can even damage it. Wait until the glass is cold.
Does the same method work on the glass of a cassette fire?
Yes. The glass on a cassette fire or insert is cleaned in the same way: door open, cold glass and damp ash. Take particular care with the seal, which is usually very close to the glass.