Dimplex BF Series Built-In Electric Fireboxes Size Guide: 33"-45"

Compare 33", 39" (Standard vs Deluxe), and 45" BF Series models to confirm framed opening (cutout), depth, and 120V/240V electrical planning before you buy.

How to measure (60 seconds)

  • Choose your width: 33" (small spaces), 39" (most common), or 45" (largest focal point).
  • Frame to the cutout: match your framed opening to the Rough opening / cutout values in the fit table.
  • Confirm depth: plan for 15" minimum (BF33) or 16" minimum (BF39/BF45) framed cavity depth.
  • Power plan: choose 120V for standard heat or 240V for higher heat output; hardwire is the cleanest built-in install.
  • Front clearance: keep combustibles 36" from the front of the firebox.
Clearance note
BF Series fireboxes are designed for built-in installation. Maintain a clear zone in front of the unit—keep furniture, drapes, bedding, and other combustibles at least 36" from the front.

Fit requirements table (hard constraints)

Use the Rough opening / cutout as your framing target. “Viewing area” below uses the approximate glass-door opening size commonly paired with each firebox size (helpful for visual scale planning).
Size Model (SKU) Viewing area (W×H) Firebox actual (W×H×D) Rough opening / cutout (W×H×D) Heat (standard) Heat (optional) Power + breaker Link
33" BF33DXP ~29 1/8" W × 18 1/4" H 32 3/4" W × 28 1/2" H × 14 1/4" D Cutout (min.): 33 1/2" W × 29 1/2" H × 15" D 120V (typ.) ~4,900 BTU 240V (typ.) up to ~9,200 BTU 60Hz; 15A circuit recommended.
Hardwire for the cleanest built-in install. Higher heat output available when wired to 240V.
View on product page
39" BF39STP ~35 5/8" W × 22 1/4" H 38 3/4" W × 32 3/4" H × 15 1/4" D Cutout (min.): 39 1/2" W × 33 1/2" H × 16" D 120V (typ.) ~4,900 BTU 240V (typ.) up to ~9,200 BTU 60Hz; 15A circuit recommended.
Standard model: realistic logs (molded from real wood) for a clean built-in look.
View on product page
39" BF39DXP ~35 5/8" W × 22 1/4" H 38 3/4" W × 32 3/4" H × 15 1/4" D Cutout (min.): 39 1/2" W × 33 1/2" H × 16" D 120V (typ.) ~4,900 BTU 240V (typ.) up to ~9,200 BTU 60Hz; 15A circuit recommended.
Deluxe model: Inner Glow Logs + brick-look interior for maximum authenticity.
View on product page
45" BF45DXP ~41 5/8" W × 22 1/4" H 44 3/4" W × 32 3/4" H × 15 3/8" D Cutout (min.): 45" W × 32 7/8" H × 16" D 120V (typ.) ~4,900 BTU 240V (typ.) up to ~9,200 BTU 60Hz; 15A circuit recommended.
Largest BF Series firebox for maximum viewing width and statement installs.
View on product page

Installation planning selector

Choose your planning focus to see the right notes (wiring + aesthetics).
120V vs 240V: same framing, different heat output
Framing dimensions stay the same. Choose 120V for standard supplemental heat, or wire to 240V if you want higher heat output (common for larger rooms and commercial spaces).
Dedicated circuit (recommended)
While a dedicated circuit isn’t always required, it helps prevent nuisance trips—especially if the fireplace shares a line with outlets, lighting, or AV equipment.
Tip: For the cleanest built-in look, plan a hardwired connection and place the junction box where permitted by the manufacturer instructions.
BF39STP (Standard) vs BF39DXP (Deluxe)
Both 39" models fit the same framing opening and provide similar heating capability. The Deluxe (DXP) adds premium realism features (Inner Glow Logs and a brick-look interior) for a more authentic hearth presentation.
Choosing by room “feel”
Pick Standard for a clean built-in look and great value; pick Deluxe when the fireplace is the room’s primary design feature and you want the highest detail level.

Size-by-size guidance (recommendations)

Use the fit table above as the source of truth for framing. The notes below are shopping guidance to help you choose faster.

33" model

BF33DXP
Best for: Small bedrooms, home offices, or apartments.
Why: Its compact footprint allows for a traditional fireplace look in tight spaces where a full-sized mantel or masonry fireplace would be impossible.
Firebox actual: 32 3/4" W × 28 1/2" H × 14 1/4" D
Cutout (min.): 33 1/2" W × 29 1/2" H × 15" D
Viewing area (approx.): 29 1/8" W × 18 1/4" H

39" Standard model

BF39STP
Best for: Standard residential living rooms or commercial waiting areas.
Why: Offers the Standard experience with realistic logs molded from actual wood that glow in concert with the flames. It’s a versatile choice for a clean, built-in appearance.
Firebox actual: 38 3/4" W × 32 3/4" H × 15 1/4" D
Cutout (min.): 39 1/2" W × 33 1/2" H × 16" D
Viewing area (approx.): 35 5/8" W × 22 1/4" H

39" Deluxe model

BF39DXP
Best for: High-end residential living rooms or executive offices.
Why: Offers the Deluxe experience featuring Patented Inner Glow Logs that pulse from within and a brick-look interior for maximum authenticity.
Firebox actual: 38 3/4" W × 32 3/4" H × 15 1/4" D
Cutout (min.): 39 1/2" W × 33 1/2" H × 16" D
Viewing area (approx.): 35 5/8" W × 22 1/4" H
BF39STP vs BF39DXP (quick compare)
  • Logs: STP = realistic molded logs; DXP = Inner Glow Logs that pulse from within.
  • Interior: DXP adds a brick-look interior for a more traditional masonry feel.
  • Fit: Same 39" chassis and same cutout dimensions—choose based on realism/detail level.

45" Deluxe model

BF45DXP
Best for: Large grand rooms, master suites, or commercial lobbies.
Why: As the largest model, it provides a commanding architectural presence and the widest viewing area for a high-impact focal point.
Firebox actual: 44 3/4" W × 32 3/4" H × 15 3/8" D
Cutout (min.): 45" W × 32 7/8" H × 16" D
Viewing area (approx.): 41 5/8" W × 22 1/4" H

View product page and availability

Check current stock, see pricing, and confirm finish options on the main product page.
Safety, clearance, framing, and electrical notes are summarized from Dimplex BF Series manuals and manufacturer sell sheets. Always follow the manufacturer installation instructions and local electrical code. Use a qualified electrician for hardwire installation and 240V configurations.