The Belgian house Stûv builds fireplaces the way an architect draws a room — by taking things away until only what matters is left. The Stûv 21, drawn by the company's founder Gérard Pitance, is the clearest expression of that idea: a fireplace pared back to a slim steel frame around a wide, shallow firebox, so that almost nothing stands between you and the fire. No heavy surround, no ornament, no thick black frame breaking up the view. Just a clean rectangle of flame set into the wall like a picture.

What makes it more than a handsome opening is what the frame hides. The glass front is a guillotine — a single frameless pane that rises straight up and disappears into the structure above. It is the whole idea of the 21 in one movement, and it changes what the fireplace is.

Lower the glass and the 21 is a closed, controlled wood fire — drawing its air precisely, re-burning its own smoke, and pushing that heat back into the room through convection channels built into the body. It is efficient, calm, and clean, the way a modern wood fireplace should be.

Raise the glass and it becomes something older and rarer: an open hearth, with the sound and the scent and the direct radiant warmth of a real open fire, and nothing in the way of it at all. One fireplace, two entirely different evenings — the everyday efficiency of a closed fire, and the occasional romance of an open one, chosen with a single hand movement. Few fireplaces made today can do both. Fewer still make the switch look this effortless.

The 21 is really a family, not a single model. It comes in a run of widths — from a compact firebox to one nearly four feet across — so it can be scaled to the room rather than the room built around it. Choose it single-faced to set into a wall in the usual way, or double-faced to run the fire straight through a wall as a see-through, so a single hearth warms — and connects — two rooms at once. It burns full-length 16-inch logs, and its insulated steel shell lets it be built safely into ordinary framed, combustible walls, which gives an installer real freedom in where it can go.

That range is exactly why we love placing it. A fireplace this minimal asks everything of the wall it lives in — the reveal has to be crisp, the proportions right, the finish carried cleanly to the very edge of the glass. Getting that quiet perfection is the work, and it is precisely the kind of Creative FireSpace™ we take on: the measuring, the framing, the flue, and the careful detailing that makes a fire look as though it was always part of the architecture.

Not every room wants a wall built around its fire. For those, there is the Stûv 21 Clad — the same frame-and-guillotine fire, but delivered already dressed. Rather than a firebox you finish on site, the Clad arrives wrapped in its own casing: a clean, self-contained block that stands in the room as a single sculptural object, complete from the moment it's set down.

It's the difference between building the fireplace into the architecture and setting the architecture down whole. The Clad comes single-faced to sit against a wall, double-faced to divide and warm two spaces at once, and in a wider three-sided form that opens the fire on the front and both returns. For a renovation on a schedule, or a room where you'd rather not open up a wall, it's the shortcut to everything the 21 does — with far less on-site work.

And it can be dressed to taste. Stûv's finishes run from soft whites and warm greys to a deep matte black and the rich, living patina of weathering steel — and several Clad models fold in an open log store beside the firebox, so the fuel itself becomes part of the composition, stacked and waiting like part of the design.

Built-in or clad, single-faced or see-through, compact or nearly four feet wide — the 21 bends to the room in a way few wood fireplaces can, which is exactly why it's one of our favourite things to place. Whichever form suits the space, the fire at the centre of it is the same: reduced to its essentials, precisely made, and quietly extraordinary.