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Gas Fireplace Inserts in Seattle, Tacoma & Everett
Turn a drafty open fireplace into a sealed, efficient gas heater. Inserts sized to your firebox, lined and tested by our qualified technician. Free quote.
- Free 2nd-opinion quotes
- Price match + 10–25% discount
- Same-day service often available
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A gas insert is a complete, sealed firebox that slides into the opening of an existing masonry fireplace. Behind its glass is a burner, a log set and usually a blower; behind the unit, two flexible liners run up the old chimney to carry exhaust out and fresh air in. Because it is sealed from the room and vents directly outdoors, an insert turns a fireplace that used to pull warm air up the flue into one that actually heats the house. This page is about inserts specifically: what they do to your chimney, how they are sized, and what the install involves.
It is different from gas fireplace installation, which is a whole new factory-built unit framed into a wall, and from gas log installation, an open burner in the firebox with no glass and no efficiency gain. If you are still deciding between a log set and an insert, the gas fireplace conversion page lays out the whole choice.
Our qualified technician measures, fits, lines and tests the insert; a qualified gas fitter runs and pressure tests the gas supply. We serve Seattle, Tacoma, Everett and the road-accessible Puget Sound from our Renton office. The quote is free, and we price match a written quote and take 10-25% off. Call 206-453-2045.
Symptoms
Signs you need gas fireplace insert
- Your open fireplace makes the room colder once the fire dies down
- You want real heat from the fireplace, not just the look of flames
- The masonry firebox is sound but the chimney is unlined or the clay tiles are cracked
- You are tired of hauling and storing firewood in a wet climate
- An old wood insert or log set is rusted, inefficient or no longer safe to use
- You want a fireplace that runs from a thermostat or remote during an outage
- A home inspection flagged the open fireplace and you want a clean, listed solution
Common causes
- Open masonry fireplaces send most of their heat and a steady stream of room air up the flue
- Older clay-tile flues crack with age and freeze-thaw, so a direct-vent liner is often the safest way to keep using the chimney
- Wet Puget Sound firewood burns cool and dirty, which is why many households stop using a wood fireplace
- Gas log sets must run with the damper open and give little net heat, which sends people looking for an insert
- Previous wood-burning inserts were often installed without a full liner and no longer vent safely
How It Works
Our gas fireplace insert process
Our technician measures the firebox at the front and back, its depth and height, and the size and height of the flue, because an insert is chosen by what physically fits with clearance and what the liner run allows. We scope the chimney to confirm it can carry two liners, look for offsets that complicate the pull, and check the damper and smoke shelf that will be removed or modified. We note where gas and power can reach the firebox and whether a hearth extension is needed. The free quote names the unit, heat output, liner kit, termination cap and any masonry or electrical work, so there are no surprises on install day.
Measure and free quote
Our technician measures the firebox and flue, discusses heat output and style, and quotes an insert that fits with proper clearances.
Prepare the chimney
The flue is swept, the damper plate removed or locked open, and any loose tile or debris cleared so the liners pull cleanly.
Gas and electrical
A qualified gas fitter runs and pressure tests the supply to the firebox; an outlet is provided for the blower and ignition where needed.
Run the direct-vent liners
Two flexible liners are pulled from the top of the chimney down to the firebox, one for exhaust and one for combustion air, and sealed at a new termination cap on the crown.
Set and connect the insert
The unit is leveled in the firebox, liners attached, gas connected, the surround trim fitted, and logs and embers placed to the manufacturer's diagram.
Fire, test and walkthrough
We run the insert through its cycles, check the flame and draft, leak test our connections, and show you the remote, blower and thermostat settings.
Options
Repair and service options
Inserts differ mainly in venting, output and finish, and the right one depends on the firebox and how you will use it:
- Direct-vent inserts: the standard choice. Sealed glass, two liners, combustion air from outside, the highest efficiency and no room air lost up the chimney.
- B-vent inserts: draw combustion air from the room and vent through a single liner. Less efficient, used where a direct-vent kit will not fit the flue.
- Heat output and blower: inserts are sized in BTU to the room, not the firebox. A variable-speed blower and thermostat control turn the insert into a zone heater.
- Surround and trim: a flat or contoured faceplate covers the gap between unit and brick, in black, bronze or custom finishes, with optional decorative fronts.
- Log and media styles: split oak, birch or driftwood logs, or glass and stone media for a contemporary look.
- Chimney work if needed: a crown repair or cap to keep rain off the new termination, or masonry repair so the chimney stays sound around the liners.
If you are not happy, we are not done, and we come back at no charge.
Pricing
What affects the price
- Insert size, BTU output, brand and finish options
- Direct-vent versus B-vent and the length and difficulty of the liner run
- Chimney height, offsets and whether the flue needs clearing to pass two liners
- Whether a gas line and an outlet already reach the firebox or must be run
- Condition of the crown and cap where the termination is sealed
- Hearth extension, surround or masonry work around the opening
- Permit fees where they apply; we will tell you if one may be needed
Every chimney is different, so you get a written quote after we look at the system. Ask about our price match and free second-opinion quote.
Safety & Seattle Conditions
Safety considerations
If you smell gas, leave the house, do not switch anything on or off, and call your gas utility or 911 from outside. Everything on the gas side of an insert, from the supply connection to the valve and burner, is done by a qualified gas fitter or our qualified technician and is not homeowner work. The sealed glass on a direct-vent insert gets very hot; a listed barrier screen is standard on new units, and we install it.
An insert must be installed in a masonry fireplace with a liner run the full height of the chimney, never simply slid into the opening to vent up the old flue. NFPA 211 recommends an annual inspection of fireplaces, chimneys and vents, and an annual gas fireplace cleaning keeps the burner, pilot and glass of the insert in shape. A carbon monoxide alarm near the fireplace is a sensible companion.
Seattle & Puget Sound conditions
Inserts are a natural fit for the region's older masonry fireplaces. Tacoma's median home dates to 1967, Shoreline's to 1969, Edmonds' to 1974 and Seattle's to 1976, and those homes tend to have brick fireboxes built for wood, often over clay-tile flues that have seen decades of freeze-thaw. Seattle sees about 60 days a year where the temperature touches 32F, and wet masonry that freezes and thaws is how tiles crack; a direct-vent liner inside that flue sidesteps the problem.
The heat matters as much as the venting. Sea-Tac's NOAA 1991-2020 normals put October through March at about 29.65 inches of rain, roughly 73% of the year's total, and winter lows hover around 37F. A sealed insert on a thermostat keeps the main living space warm through that stretch without pulling heated air up the chimney.
Our Work
Gas Fireplace Insert in action
Want real heat from your fireplace? Get a free insert quote.
Sealed gas inserts measured, lined and tested by our qualified technician. Free quote, price match plus 10-25% off. Call 206-453-2045.
☎ 206-453-2045 Request a QuoteQuestions
Gas Fireplace Insert FAQ
What is the difference between a gas insert and a gas fireplace?
An insert is built to go into an existing masonry fireplace and uses the old chimney as a chase for its liners. A gas fireplace is a complete unit framed into a wall or a new chase with its own vent pipe, used where there is no fireplace or the old one is being removed. If you have a sound brick firebox, an insert is usually the simpler and less expensive path.
What happens to my old chimney when an insert goes in?
It stays, but its job changes. The damper is removed or locked open, two flexible liners run from the insert to a new termination cap at the top, and the old flue becomes a protected chase around them. The chimney no longer handles exhaust directly, so cracked clay tiles stop being a venting hazard, though the crown and masonry still need to keep water out.
Will a gas insert actually heat the room?
Yes. That is the main reason to choose an insert over a log set. The unit is sealed from the room, draws combustion air from outside, and pushes heat through a blower, so it works as a zone heater rather than a decorative flame. Our technician sizes the BTU output to the room so it warms without overheating the space.
Does the insert need a liner all the way up?
Yes. A direct-vent insert uses two liners, one for exhaust and one for intake, that run the full height of the chimney and seal at a termination cap. Sliding an insert into a fireplace and letting it vent into the old flue is not a listed installation and is not something we will do. The liner run is part of every insert quote.
Can I put an insert in a factory-built fireplace?
Sometimes, but only with an insert that is listed for that specific prefab firebox, and many are not. Our technician reads the rating plate on the existing fireplace before recommending anything. In a masonry fireplace, the range of inserts that fit is much wider. If the prefab unit is failing, a new gas fireplace installation may be the better route.
Do I need a permit for a gas insert?
You may need one, depending on the city and the gas line work involved. We will tell you what applies at your address when we quote, and we coordinate with the qualified gas fitter on the supply side. Permit fees, where they apply, are listed separately in the quote.
How long does the installation take?
With gas and power already at the firebox and a straight chimney, most inserts are installed in a single day. Running a new gas line adds the fitter's schedule, and a tall or offset chimney can add time to the liner pull. Measuring visits are often available same-day, the quote is free, and we price match a written quote plus 10-25% off.
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