Corner fireplaces
A fireplace set diagonally into a room corner, facing outward at 45° to both adjoining walls. The triangular footprint claims the corner; the diagonal face anchors seating. Comprehensive reference covering history, dimensions, construction, when to use, and cost.
A corner fireplace sits diagonally in the corner of a room, with the firebox facing into the room at 45° to both adjoining walls. The triangular footprint claims the corner; the diagonal face anchors the seating arrangement. Compared to a standard wall-mounted fireplace (which projects into the room from one wall), a corner fireplace uses corner real estate that would otherwise be hard to furnish — and centers the room's focal point on the corner rather than on one wall.
Corner fireplaces have specific aesthetic appeal in Southwestern, mountain modern, traditional cabin, and certain mid-century architectures. They also have specific practical applications: when one or more walls are committed to windows, doors, or other features, the corner may be the only available location for the fireplace.
This page is the comprehensive reference for corner fireplaces. For the fireplace family overview, see fireplaces overview. For the dual / see-through variant, see dual double sided fireplaces.
In this guide
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What makes a corner fireplace different
Geometry. The firebox is angled at 45° to both adjoining walls. The footprint is triangular (with hypotenuse — the diagonal face — facing the room). The firebox depth extends into the corner, with the structural mass behind it hidden by the walls. Visual reading. The fireplace becomes the corner — the room's corner is replaced by the fireplace's diagonal face. The corner stops being 'just a corner' and becomes the room's focal point. Differences from a wall fireplace: - Wall fireplace: projects from one wall into the room. Center on one axis. - Corner fireplace: sits in the corner, facing diagonally. Centered on the room's diagonal. - Wall fireplace: requires real estate on one wall. - Corner fireplace: requires real estate in a corner; freeing up both walls for other features. - Wall fireplace: seating typically faces directly. - Corner fireplace: seating is oriented diagonally to face the fireplace. Differences from a dual fireplace: - Dual fireplace: embedded in an interior wall with openings on both sides (two rooms). - Corner fireplace: just one room's worth of opening, in a corner.
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Standard dimensions
Side length (each side of the triangular footprint). The distance from the corner of the room out along each adjoining wall to the edge of the fireplace. - Compact: 24–36 inches. - Standard: 36–48 inches. Most common: 36 inches. - Large: 48–60 inches. - Grand: 60+ inches. Face width (diagonal facing the room). The width of the firebox opening as seen from the room. - Compact: ~34 inches (24-inch side × √2). - Standard: ~51 inches (36-inch side × √2). - Large: ~68 inches (48-inch side × √2). Firebox depth (corner to back). The depth of the firebox going into the corner. - Compact: 12–18 inches. - Standard: 18–24 inches. - Large: 24–30 inches. Hearth height (above floor). Same options as wall fireplaces. - Floor-level (modern minimalist): 0 inches. - Traditional low hearth: 6–12 inches. - Raised hearth: 18–24 inches. Projection into room (perpendicular distance from corner). For a 36-inch side fireplace at 45°, the projection is approximately 25 inches (36 ÷ √2). A 48-inch side fireplace projects approximately 34 inches. Mantle. Optional. If included, typically a mantle shelf above the firebox face. Width: matches face width or slightly wider. Chimney path. For wood-burning corner fireplaces, the chimney rises from behind the firebox through the corner and up through the roof. The chimney is exterior to the room — the corner itself doesn't extend down to floor level (it's interrupted by the firebox).
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Construction considerations
Structural framing. A corner fireplace claims the corner of the room. The corner walls are interrupted by the firebox; the framing reroutes the structural loads around the firebox. Wood-burning corner fireplace: - Requires masonry firebox or prefab metal firebox. - Chimney rises from behind the firebox. - Chimney can rise straight up from the corner (going through floors and roof) or can route through the wall and up an exterior chimney. - Foundation: separate concrete pad for the firebox. - More structural complexity than a wall fireplace. Gas corner fireplace: - Direct-vent: sealed combustion, vents through wall. - Vent: shorter path to exterior than for a wall fireplace (corner geometry helps). - Construction simpler than wood-burning. Electric corner fireplace: - Standalone unit or built-in. - Plug into wall outlet. - Minimal construction. Surround. The surround (the finished material around the firebox) often extends along both adjoining walls. Common materials: stone, brick, tile, drywall with trim. The surround's L-shape or triangular pattern reinforces the corner geometry. Hearth. Often extends along the diagonal in front of the firebox. Made of non-combustible material (stone, tile, slate, brick).
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When to use a corner fireplace
Wall space is tight. Other walls are already accounted for by windows, doors, built-ins, or furniture. The corner is available real estate that wall fireplaces can't use. The corner is the natural focal point. Open-plan rooms where seating wraps around a corner. Rooms with the best view direction at the corner. Architectural style calls for it. - Southwestern (Santa Fe, Pueblo). Adobe and stucco architectures often feature corner fireplaces (kivas). - Mountain modern, cabin, lodge. Stone corner fireplaces are signature. - Traditional cabin. Logs or stone corner fireplaces. - Modern minimalist. Sleek glass-fronted corner fireplaces. - Mid-century modern. Sometimes corner fireplaces with built-in hearths. Multi-room open plan. A corner fireplace can be visible from multiple zones of an open plan (living, dining, kitchen) by virtue of its diagonal orientation. Where wall fireplaces would be too prominent. A 60-inch wide wall fireplace dominates one wall; a comparable corner fireplace becomes one feature among the corner's geometry. Smaller rooms. Corner fireplaces can serve smaller rooms (12×14, 14×14) where a wall fireplace would dominate.
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When NOT to use a corner fireplace
Linear, formal rooms. Federal and Colonial Revival rooms organized along a center axis don't accommodate corner fireplaces well. The diagonal geometry conflicts with the axial layout. Very small rooms (under 12×12). Even a corner fireplace projects significantly. In a small living room, the projection eats much of the floor. Corner already committed. If the corner has windows, doors, or other features, the corner fireplace doesn't fit. Mid-century traditional ranch. While modern variants of mid-century work with corner fireplaces, the standard 1950s American ranch typically uses wall fireplaces. When the surrounding walls have specific design vocabulary. A formal room with built-in bookshelves on one wall and a wall fireplace tradition doesn't want a corner fireplace.
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Furniture layout around a corner fireplace
Diagonal seating. Furniture is oriented to face the firebox's diagonal face. This means furniture itself is angled rather than orthogonal — a sofa parallel to the diagonal, or two chairs at angles. Sample layout 1 — Diagonal seating with sectional. - Corner fireplace in one corner. - L-shaped sectional with the long side parallel to one wall (perpendicular to one of the fireplace's sides). - Coffee table between sectional and fireplace. - Accent chair on the other diagonal. Sample layout 2 — Conversation around corner. - Corner fireplace. - Sofa parallel to one of the fireplace's sides (perpendicular to the diagonal). - Two chairs facing the sofa. - Coffee table between. Sample layout 3 — Open-plan diagonal axis. - Corner fireplace at the corner shared by living and dining zones. - Living seating oriented to face the fireplace from one side. - Dining table oriented to view the fireplace from the other side. - The fireplace serves both zones. Mantle decorating. The mantle on a corner fireplace is the diagonal face. Decorative items should be arranged in a layered composition (not a single row of items as on a wall mantle).
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Cost ranges — US 2024 installed
Corner fireplaces cost about 10–20% more than equivalent wall fireplaces because of additional structural complexity and the diagonal geometry. Specific ranges: Wood-burning corner fireplace (new construction): - Prefab insert with metal flue: $4,500–10,000. - Masonry with stone surround: $25,000–60,000. Gas direct-vent corner fireplace: - Standard 36-inch face: $3,500–7,500. - Premium with stone or tile surround: $6,000–15,000. Electric corner fireplace: - Standalone: $400–2,500. - Built-in with surround: $1,500–5,000. Retrofit (existing wall): - Wood-burning retrofit: $30,000–60,000+ (significant structural and chimney work). - Gas retrofit: $5,000–12,000. - Electric retrofit: $500–3,000. Corner fireplace costs are higher in retrofit because of the structural rework of the corner.
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In Room Sketch 3D
After clicking the Corner Fireplace tile in the Build Panel and clicking on a room corner, the Inspector exposes: - Side length. Length of each side of the triangular footprint (typically 36 inches). - Hearth height. Above floor (typically 0–18 inches). - Color. For the firebox and surround. The firebox auto-aligns to the corner at 45° to both adjoining walls. In 3D View, the corner fireplace renders with the diagonal face facing into the room, hearth at the specified height, and stone or tile surround. The chimney for wood-burning configurations renders as a vertical extension above the firebox. Smart Flow Check treats the projection as obstructed floor space; furniture is checked against the triangular footprint.
Tips
Match style to architecture
Southwestern with stucco surround; mountain modern with stone; modern with sleek frameless gas. Don't mix — corner fireplaces are style-specific.
Furniture diagonal to match
Seating should orient toward the diagonal face, not toward one of the walls. This often means furniture itself is angled rather than orthogonal.
Consider sightlines from adjacent zones
Corner fireplaces are visible from multiple zones of an open plan. Plan layout so the fireplace is visually accessible from where people sit (living seating, dining table).
36 inches is the residential sweet spot
Wider than 36 inch side dominates small rooms; narrower than 36 inches reads cramped. 36 fits most residential applications.
Common confusions
Linear formal room with corner fireplace
Federal and Colonial rooms are organized axially. The diagonal geometry of a corner fireplace conflicts with the linear layout. Use a wall fireplace instead.
Tiny room with corner fireplace
Below 12×12, the projection eats too much floor. Use a flush wall fireplace or skip the fireplace altogether.
Frequently asked questions
What is a corner fireplace?
A fireplace set diagonally into the corner of a room, facing the room at 45° to both adjoining walls. The triangular footprint claims the corner; the diagonal face anchors the seating arrangement.
How big is a corner fireplace?
24–60 inches per side of the triangular footprint. 36 inches is the most common residential size. The face width (diagonal opening) is approximately the side length × √2, so a 36-inch side has a ~51-inch face.
Are corner fireplaces more expensive than wall fireplaces?
About 10–20% more in new construction, because of the corner structural rework. Wood-burning retrofit corner fireplaces can be significantly more expensive due to the chimney routing.
What architectural styles use corner fireplaces?
Southwestern (Santa Fe, Pueblo), mountain modern, traditional cabin/lodge, modern minimalist, mid-century modern. Less common in formal Federal, Colonial Revival, Tudor, or traditional Victorian.
How do I add a corner fireplace in Room Sketch 3D?
Build Panel → Fireplace section → Corner Fireplace tile. Click, then click the corner of the room. Set side length and hearth height in the Inspector.
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