How we judge and rank

Everything below is written so it can be held against the pages it produced. A method that cannot be checked against its own output is a statement of intent; each rule here therefore names what it rules out, not only what it favours.

The fuel decides before the appliance does

This is the one subject where the cheapest variable outweighs every purchase on the site, so it is read first. Wet wood does not burn badly — it spends the first part of every load boiling water out of itself, and the heat for that comes out of the room. No appliance in any family here recovers what a damp log takes away.

So a page reports what the maker states its appliance was designed and tested for: the moisture content, the log length the firebox accepts, the fuel classes approved, and whether briquettes or anthracite are permitted at all. Where the documentation says nothing, the page records the silence, because on this shelf the silence is itself informative.

Then whether it physically goes in

Before any figure that flatters, a page asks whether the thing will connect to the chimney already in the house and pass through the door already in the frame. These are millimetre questions, and a photograph answers none of them.

In practice: the flue spigot diameter, 120, 130, 150, 160 or 180 mm, which meet nowhere in between. Whether the outlet leaves at the top or the rear, and whether the maker allows it to be moved. The door cord groove, sized 6, 8, 10 or 12 mm. The glass, which is cut to one outline and one thickness. The grate, ordered by two dimensions and a casting. The clearance to combustible material behind and beside. Where a maker publishes none of it, the page says it was not published — which tells you something about the listing.

Nothing numeric appears without its source

Every number on this site sits beside the party that wrote it down. Not in a footnote, not implied by a certification badge — beside it, in the same table row or the same sentence.

The reason is practical. A figure with a source attached can be traced, argued with, or corrected by anyone who writes in. A figure without one can only be taken on trust. Where an instruction manual and a marketplace listing disagree, the manual is what appears. Where neither publishes anything, the field stays empty and the page says it is empty — because once a plausible substitute has been typeset, nothing on the page separates it from a measurement.

The headline number arrives with its condition

What a listing puts in the largest type comes next, and it comes carrying whatever the listing left out. A nominal output with the fact that it is one point on a curve rather than a range. An efficiency percentage with the standard it was measured under. A heatable volume with the insulation standard it assumes, or with the note that none was stated. A minimum draught in pascals, which belongs to the chimney and not to the stove.

Where the number is printed and the condition omitted, the omission is the finding. Two appliances quoting the same nominal output can be describing quite different things, and the condition is usually the whole of the difference.

Four questions about the fifth winter

• The part that fails first, and whether it is sold on its own. Door cord, glass, firebricks or vermiculite, grate, ash pan, baffle plate, pellet igniter, door hinge: every family has one. The page names it and says whether a spare exists, because that single fact separates an appliance with a service life from an appliance with a component life.
• What the crate does not contain. The flue pipe a stove needs and never ships with. The wall sleeve the chimney connection requires. The floor plate the building rules ask for. The spare cord and its adhesive. Anything that has to be bought before the first fire was never the price on the label, and the page puts the difference back.
• What the house has to provide. A chimney of the stated diameter and effective height. The draught the maker specifies, in pascals. A combustion air supply where the appliance is sealed to the room. A floor able to carry two hundred kilos on four small feet. These get published often enough to compare, and they rule an appliance out rather than ranking it.
• Whether your own store actually sells it. Each reference is confirmed on every market before a page is published, and each page names the stores where an offer existed. Excellent equipment that nobody stocks in your country is a frustration rather than a recommendation.

Which document loses an argument

For anything dimensional — spigot diameters, cord thicknesses, glass outlines, grate sizes, clearances, what a spare states it fits — the manufacturer's own documentation is read first and the marketing headline last. The order reverses for whatever is set in the largest type on the box, for the plain reason that the largest type exists to sell.

Approvals and emission classes come second, and they are treated as claims awaiting re-confirmation rather than permanent properties. A maker revises a baffle, a grate or a supplied cord without changing the model name, and a standard is revised on a schedule of its own.

Owners several winters in come third, and on one question nothing replaces them. No specification sheet records whether a door still shuts tight in its fourth year, whether the paint has held above the outlet, whether the glass stays clear at low output, or whether anyone answers the spares address. Where a judgement rests mainly on one of the three, the page says which. Where none of the three answers, the page says so rather than reasoning its way to a number.

Transcribed, never calculated

This shelf sells on numbers, and a number is the easiest thing in a listing to repeat without thinking. One rule governs every page that carries one: every output in kilowatts, efficiency percentage, heatable volume, flue diameter, required draught, flue gas temperature, mass flow, emission figure, firebox depth, log length, appliance weight and burn time on this site is copied from the manufacturer, in the unit it was published in, with its source named — and not one of them is recalculated, converted or inferred here. Where a maker publishes nothing at all, the page records the silence.

The heatable volume is where that rule pays for itself. Multiplying an output by a rule-of-thumb factor takes a moment, and the result would look entirely authoritative set in the same typeface as everything around it. It would also be our figure rather than the maker's, resting on an insulation standard nobody stated, and nothing in the typography would tell you which of the two you were reading.

A place in a family, never a mark out of ten

Nothing here carries a score. A single mark would have to weigh a nine-kilowatt stove against a tub of firelighters, and there is no honest exchange rate between those two things. What a page gives instead is a position within one family, with the sentence that earned it printed alongside.

Families are built from the modest upward rather than the expensive downward. Nearly everyone arrives with a budget already fixed and one particular gap to fill; a page that opens on the dearest thing on the shelf is answering a question nobody brought.

One distortion belongs to this subject specifically, and naming it works better than resisting it quietly. Wood heating is sold on output figures far beyond what an insulated room can absorb. Build a page around those and it recommends the biggest number in every family, because a bigger number can always be argued for. An oversized stove is run throttled, which is the condition in which it smokes, tars its glass and fouls its flue. Where the honest answer is that the larger appliance would make the room worse, that is the answer the page gives.

One bias cannot be structured away. This site covers what can be bought through the Amazon stores of the United States, the United Kingdom, Germany, France, Italy and Spain. Appliances sold only through installers or heating merchants are under-represented here as a result, and wherever that shapes a conclusion the page says so.

The two sentences you will not find here

Both limits are fixed, and both read better stated outright than left to be inferred. Nothing here — no stove, no liner, no floor plate, no carbon monoxide alarm — is described as making anything safe. A page reports what the maker specifies for its own product: the clearance cited, the arrangement that clearance assumes, the materials, the fixing, the inspection interval and the parts due for replacement. The rest belongs to those instructions and to the rules where you live, because whether an installation is safe depends on the chimney, the structure around it and the person who commissioned it — and no listing knows any of that.

And no page here says what your room needs. A heatable volume is a property of a product measured against an assumed building. What a particular house requires depends on its insulation, its air changes, its layout and the winter it stands in — none of that is printed on any carton, none of it is ours to state, and it is the one recommendation this site is structurally unable to make honestly.

Where the page stops and the manual starts

None of this replaces the manufacturer's instructions. For the clearance to combustible material, for the flue cross-section and effective height an appliance assumes, for the combustion air a sealed room requires, for the commissioning and sweeping a local authority demands, and for what may never be burned in a firebox, the page points at those documents rather than rewording them — even though a page that stops there earns nothing.

One last limit is repeated on every page it touches rather than stated once here and assumed afterwards: compatibility is decided by a dimension or a list that a manufacturer put in writing, and never by two objects appearing to match. A spigot diameter decides which pipe meets which stove. A cord thickness decides which seal sits in which groove. A glass outline decides which pane a door will hold. A grate's two dimensions decide which casting drops into which firebox. Where a maker publishes none of it, the page reports the answer as unpublished rather than deducing it from a photograph or a model name.