How you light a fire has a direct and measurable impact on creosote buildup. A fire lit correctly — dry wood, top-down, flue pre-warmed, air fully open — burns hotter and cleaner and deposits far less creosote than a smouldering, bottom-up, wet-wood fire. Over a Melbourne winter, the difference adds up: better technique means a cleaner flue, fewer safety risks, and more heat from the same amount of wood. This guide covers the technique step by step.

Top-downThe cleaner, more effective method
Full airflowFirst 20–30 minutes is critical
Below 20%Target moisture content for wood

The Top-Down Lighting Method

The top-down method is the most effective way to light a wood fire with minimal smoke and rapid establishment. It is now recommended by most wood heater manufacturers and produces noticeably less creosote than the traditional bottom-up approach.

The setup from bottom to top: two or three large logs on the floor of the firebox, positioned with a small gap between them. A layer of smaller logs or split wood across the large logs, again with air gaps. A layer of dry kindling across the smaller logs. Two or three sheets of scrunched newspaper or a natural firelighter at the very top. Light the paper or firelighter at the top.

The reason it works: the flame burns downward into dry, preheated wood rather than upward into the underside of damp logs. Combustion gases rise through active flame, burning off before they can reach and condense in the cool upper flue. The fire establishes quickly, the flue heats up faster, and the early minutes of burning — the highest-risk window for creosote formation — are much cleaner.

Warming a Cold Flue

This step is overlooked most often, and skipping it is why so many Melbourne living rooms fill with smoke at the start of winter.

A cold flue — especially one that runs up an external wall or has sat unused all summer — holds a column of cold, dense air that resists the warm air the fire is trying to push upward. Light the fire into a cold flue and it will often smoke back into the room, even if everything else is correct.

The fix is simple: before laying or lighting the main fire, hold a lit roll of newspaper or a firelighter up inside the firebox, near the open damper, for 30 to 60 seconds. You can feel and sometimes hear when the draught reverses and starts drawing upward. Once that happens, build and light the main fire normally. This single step prevents most early-season smoke problems in Melbourne homes.

Melbourne TipThe first cold snap of May is when most people have trouble — the flue has been cold all autumn and really resists drawing. Pre-warm for a full minute rather than 30 seconds, and if the flue still will not draw, have it inspected. A summer's worth of debris or animal activity can block a flue completely.

Air Management for Clean Burning

Air control is where most creosote comes from in well-run homes, because the temptation to choke the heater down overnight is high — and damaging.

When lighting: open all air vents fully. Full airflow gets the fire established quickly and the flue up to operating temperature, which is when creosote is least likely to form. Keep vents fully open for the first 20 to 30 minutes at minimum, until the fire is burning strongly and the flue is clearly drawing well.

For a sustained burn: you can reduce air slightly once the fire is established, but never so far that combustion becomes incomplete. A visibly smoky, dark-flamed fire is a sign of insufficient air. The ideal is a bright, lively flame with good draw. For a wood heater specifically, running a moderate sustained burn — rather than alternating between roaring and choked — produces better heat and far less creosote than the overnight-smoulder approach many people use.

If keeping a fire overnight is important to you, the better technique is to load up with large dense hardwood just before bed on full air, let it burn down to a good coal base, then reduce air moderately — not all the way closed. A coal bed maintains heat without producing the creosote a smouldering log does.

Key PointThe single most creosote-generating habit is lighting a fire, then immediately choking the air down to almost nothing to slow the burn. This gives you a cool, smoky, slow-combusting fire that deposits creosote rapidly. Better to burn less wood at a higher output than more wood at a smoulder.

Common Mistakes That Build Creosote

The most common errors FreshDuct technicians see in Melbourne homes, and how to avoid them.

Burning wet wood. The most widespread problem. Wet wood smokes heavily, burns cool and deposits creosote at up to three times the rate of properly seasoned hardwood. If the fire hisses, steams or produces a lot of dark smoke, the wood is too wet. See our guide to the best firewood for Melbourne.

Skipping flue pre-warming. Leads to smoke entering the room, incomplete combustion in the early minutes, and early-stage creosote deposition when the flue is at its coldest.

Choking the fire down immediately after lighting. The worst of both worlds: the fire never gets hot enough to draw well, smoke enters the room, and creosote forms at a high rate during the coldest part of the burn cycle.

Never getting the flue checked. Good technique reduces creosote but does not eliminate it. Annual professional cleaning and inspection removes what has built up and confirms the flue is structurally sound. See how often you should clean your chimney.

Frequently Asked Questions

What is the top-down fire lighting method?
The top-down method places the largest logs at the bottom, smaller logs on top, then kindling, then newspaper or a firelighter at the very top. You light it at the top and let the flame burn downward. It produces far less smoke than the traditional bottom-up approach because the fire burns into dry wood rather than damp-underside wood, produces a stronger draught earlier, and the combustion gases pass through active flame before exiting the flue. Most wood heater manufacturers now recommend it.
Should I pre-warm the flue before lighting a cold fireplace?
Yes – especially in winter. A cold flue, particularly an external one running up an outside wall, creates a cold air column that resists draught. Lighting a fire directly into a cold flue often results in smoke backing into the room. Pre-warm by holding a lit roll of newspaper or a firelighter up near the open damper for 30 to 60 seconds before lighting the main fire. Once the warm air starts drawing upward, light the fire normally.
How open should the air vents be when lighting a fire?
Open them fully when lighting and for the first 20 to 30 minutes. Full airflow gets the fire established quickly and the flue up to temperature, which is when creosote is least likely to form. Once the fire is burning well and the flue is hot, you can reduce air slightly for a slower burn, but never choke it down so far that combustion becomes incomplete. A visibly smoky, smouldering fire with vents nearly closed is producing creosote at a high rate.
Why does my fire smoke when I first light it?
The most common causes are a cold flue that has not been pre-warmed, a blocked or dirty flue restricting draught, wood that is too wet or green, or a damper that is not fully open. Light the flue first with newspaper before lighting the main fire, ensure the damper is completely open, and check the wood is properly seasoned. If the flue is clean, the damper is open and the wood is dry but smoke still enters the room, the chimney may need inspection for a draw or structural problem.
Does how I light a fire really affect creosote buildup?
Yes, significantly. Fires lit with full air supply, using dry wood and the top-down method, burn hotter and produce far less creosote than smouldering, choked-down or wet-wood fires. The flue temperature during the first 20 minutes of a fire determines whether volatile gases condense as creosote or burn off completely. A well-lit, well-run fire does genuinely minimise buildup over a season, which extends the interval before professional cleaning is needed.

Need Your Chimney Cleaned Before Winter?

Call or book online — no obligation, no fee to quote. 7 days across Melbourne.