Gas Insert Guide · Eastside WA
What makes a good gas insert? How does the brand personality differ between Heat & Glo, Valor, Mendota, and Napoleon? What does installation actually involve? This is the guide.
Start here
Before brand, before BTU, before style — one question separates your options cleanly. Everything else follows from the answer.
Path A
Do you have an existing masonry or prefab fireplace?
An existing firebox means you can use a gas insert — the most cost-efficient upgrade. You keep the chimney structure and surround, and replace only the open firebox with a sealed, efficient gas unit.
Path B
No existing fireplace — new build or open wall?
Without an existing firebox, you're looking at a direct-vent built-in. The unit vents through the wall or roof — no traditional chimney required. More design flexibility, more installation scope.
Path A — Gas fireplace insert
A gas insert slides into your existing masonry or prefab firebox and connects to a new stainless steel liner run down your chimney. You keep the surround, the hearth, and the chimney — you're replacing the open box with a closed, efficient unit.
This is the most common gas fireplace upgrade on the Eastside. Most installs are complete in one day. Every install gets a mechanical and gas permit from the city and passes inspection.
Firebox opening
Width, height, and depth determine which models fit. We measure before speccing any unit.
BTU range
Most Eastside homes use 30,000–50,000 BTU inserts. Large open-plan rooms need the higher end.
Liner required
Every gas insert needs a new stainless flex liner sized to the unit's flue requirements.
Best inserts for Eastside homes
Heat & Glo Escape Series
Wide firebox opening view, IPI ignition, multiple face options. Works in most standard masonry openings. The most-installed insert on the Eastside.
Napoleon Oakville Series
Clean aesthetic, large glass, reliable IPI. Three sizes covering most firebox dimensions. Strong value at the mid-tier price point.
Mendota FullView Series
Premium American-made insert. Exceptional glass clarity and flame presentation. For homeowners who want the best view in the room.
Valor Horizon Series
Radiant heat technology — heats the room via radiant panels, not just convection. Outperforms on efficiency in open-plan spaces.
Path B — Direct vent gas fireplace
No existing fireplace? A direct-vent gas fireplace pulls combustion air from outside and exhausts through the same pipe — either co-axially through the wall, or up through the roof. No masonry chimney required.
This is where the full design conversation happens. Linear, traditional, double-sided, see-through, peninsula — the form factor is wide open when you're starting from scratch.
Linear
Wide, low-profile flame bed. Best for modern interiors and open-plan great rooms. Napoleon Elevation, H&G ST Series, Mendota DXV.
Traditional
Classic arched or rectangular viewing window with log set. Heat & Glo 6000CLX, Napoleon Ascent. Works in most room styles.
Double-sided / see-through
Shared flame between two spaces. Dining room to living room, bedroom to bathroom. Montigo and H&G multi-sided series.
Peninsula / three-sided
Fireplace projects into the room on three sides. Statement piece for large open spaces. Montigo and Napoleon Altitude series.
What determines install complexity
Choose by what matters most
Once you know insert vs. direct vent, priority narrows the brand. Here's what each priority points to on the Eastside.
If you want…
Efficiency & heat output
→ Valor
Valor's radiant heat panels warm surfaces and people directly — not just the air. Outperforms convection-only units in open-plan spaces and rooms with high ceilings. The most efficient gas fireplace per BTU on the market.
Valor Horizon (insert) or Portrait (built-in)
If you want…
Design & flame presentation
→ Mendota or Napoleon
Mendota's FullView and DXV series have the best glass clarity and flame staging of any brand we carry. Napoleon's Elevation and Oakville are the design-forward choice at a lower price point. Both photograph well.
Mendota FullView or DXV · Napoleon Elevation
If you want…
Maximum heating capacity
→ Heat & Glo
H&G's SupremeX series leads on BTU output at the high end. For a large Eastside great room or open kitchen-to-living layout, H&G reaches the BTU ceiling that others don't. Multi-zone blower included.
H&G SupremeX or SL Series
If you want…
Low maintenance & reliability
→ Heat & Glo or Napoleon
Both H&G and Napoleon have been Eastside staples for 20+ years. Parts are widely available, firmware and electronic components are well-supported, and technician familiarity is high. If you want the fireplace to work without thinking about it, either brand delivers.
H&G 6000CLX · Napoleon Ascent
If you want…
Best value for quality
→ Napoleon
Napoleon hits the best price-to-performance ratio in the mid-tier. Oakville inserts and Ascent built-ins give you large glass, clean flame presentation, and solid reliability at a price point below Mendota and Valor. Strong resale value.
Napoleon Oakville (insert) or Ascent (built-in)
If you want…
Something nobody else has
→ Montigo
Montigo builds double-sided, peninsula, and custom commercial units that nobody else makes in quite the same way. If you want a see-through fireplace between two rooms or a three-sided showpiece, Montigo is the right conversation.
Montigo P-Series · H-Series double-sided
Brands we install
We're an installer for every brand we carry. That means manufacturer pricing, full warranty coverage, and access to the full model line — not just whatever's in stock at a big-box retailer.
Brands we install
Heat & Glo
The most-installed gas fireplace brand on the Eastside. H&G's range covers every price point from mid-tier to premium, and their parts availability is unmatched. The Escape insert is the right call for most standard masonry openings. For new construction, the SL Series linear and SupremeX built-in are the go-to specs.
Best for
Inserts + high-output built-ins
Lineup
Escape, SL Series, SupremeX, 6000CLX
Strengths
Range, BTU ceiling, parts availability
Price tier
Mid to premium
Brands we install
Napoleon
Napoleon is the design-forward choice at the mid-tier price point. The Oakville insert has one of the largest glass windows in its class. The Elevation linear and Ascent built-in are among the cleanest-looking gas fireplaces we install. Canadian-made, well-supported, and strong on resale value.
Best for
Design-forward inserts + linear
Lineup
Oakville, Ascent, Elevation, Aurora
Strengths
Glass size, aesthetics, value
Price tier
Mid to upper-mid
Brands we install
Valor
Valor builds the most efficient gas fireplaces on the market using radiant heat technology. Where most fireplaces blow warm air through a convection system, Valor's radiant panels heat people and surfaces directly — the same principle as the sun. The difference is tangible in high-ceiling rooms and open floor plans where convection-only units underperform.
Best for
Efficiency + open-plan rooms
Lineup
Horizon (insert), Portrait, G4, L1
Strengths
Radiant heat, efficiency, no blower needed
Price tier
Upper-mid to premium
Brands we install
Mendota
Mendota is the premium American-made option. Their FullView and DXV series have the clearest glass and best flame presentation of any brand we carry — the fire looks real because of how the burner and glass are engineered together. Built in Madison, Wisconsin. Mendota is sold through specialist installers only — no big-box retail. You get it through someone who knows how to install it correctly.
Best for
Premium installs, flame presentation
Lineup
FullView (insert), DXV, Horizon Linear
Strengths
Glass clarity, flame staging, build quality
Price tier
Premium
Quick reference
| Brand | Made in | Best for | Has insert? | Has linear? | Tier |
|---|---|---|---|---|---|
| Heat & Glo | USA | Range + high BTU output | Yes — Escape | Yes — SL Series | Mid–Premium |
| Napoleon | Canada | Design + value | Yes — Oakville | Yes — Elevation | Mid–Upper-mid |
| Valor | Canada | Efficiency + open rooms | Yes — Horizon | Yes — L1 | Upper-mid–Premium |
| Mendota | USA | Premium flame presentation | Yes — FullView | Yes — DXV Linear | Premium |
| Montigo | Canada | Double-sided / custom | No | Yes + multi-sided | Premium |
| Superior | USA | Broad compatibility | Yes | Yes | Entry–Mid |
Google reviews
“The technician found a minor problem that I would have overlooked during a chimney inspection. He gave me straightforward repair options and a clear explanation without putting any pressure on me.”
Kathleen Kimura
Verified Google review
“We noticed some cracks in the chimney and weren't sure how serious they were, but they carefully inspected everything and only recommended the repairs that were actually needed. The whole process was smooth and well-organized, and the chimney now looks solid and secure again.”
Emanuel Leavitt
Verified Google review
“I'm really impressed with the service we received for our new pellet stove installation. Everything was done carefully to spec, and they took the time to clearly explain the safety steps, which made us feel confident using it.”
Bruce Cropper
Verified Google review
“The technician spotted minor damage to my chimney crown that I hadn't noticed and quickly took care of it. He explained the repair options clearly and made sure everything was solid, which I really appreciated for his honesty and skill.”
Jean Hill
Verified Google review
“Prime Chimney was suggested by a neighbor, and I now see why. They were easy to book, arrived on time, and completed a thorough job. The technician was courteous and left no mess. Our chimney is clean, safe, and ready for the colder months. Wonderful local enterprise!”
Manuel Laporte
Verified Google review
Common questions
Questions we get on almost every insert consultation. Straight answers.
Ask us directlyFree in-room consultation
We measure the firebox or wall, talk through the brands, and write up a clear estimate. No pressure, no guesswork. Serving Bellevue, Kirkland, Redmond, and the Eastside.
Schedule a consultation