The Part of the Fireplace That Keeps the Fire in the Fireplace
Everything you see when you look into your fireplace is the firebox: the firebrick walls and floor of a masonry fireplace, or the grey refractory panels of a factory-built one. Its only job is to take the heat so the wall behind it does not. When a brick cracks, a mortar joint falls out, or a panel splits, heat starts reaching the steel or the framing. A firebox problem does not smoke, smell or make noise. It just quietly gets worse until someone looks.
Crownline Chimney Sweep repairs fireboxes in Arlington, TX from our office at 700 Highlander Blvd near the Parks Mall and I-20. Our masonry crew has repaired firebrick, mortar and refractory panels in Arlington fireplaces for more than 20 years. We are insured and bonded, the estimate is free, and the price is in writing before we mix a bag of mortar. Call (817) 505-4222 any day, 7 AM to 10 PM.
Two Kinds of Firebox, Two Kinds of Repair
Masonry firebox. Built on site from firebrick laid in refractory mortar, with a sloped back wall and a steel lintel over the opening. Standard in Arlington’s 1950s to 1970s brick homes around Old Arlington, UTA, Fielder Park and Dalworthington Gardens. Repairs are masonry: repointing joints, replacing bricks, rebuilding the lining.
Factory-built firebox. A steel box lined with refractory panels, set in a framed chase. Standard in the 1980s to 2000s two-story homes in Southwest Arlington, Interlochen and near Lake Arlington. Repairs are part replacement: new panels to the manufacturer’s spec, and a check of the steel behind them for rust from a leaking chase cover.
Both get the same first step: a close look at every joint and panel with a light, and photos of what we find.
Firebox Repair Services in Arlington, TX
Repointing firebrick joints. Loose and crumbling mortar raked out to sound depth and repacked with refractory mortar rated for the heat. The most common firebox repair in Arlington and the cheapest, if it is done before bricks loosen.
Firebrick replacement. Cracked, spalled or loose bricks cut out and replaced with matching firebrick. One brick or a dozen.
Refractory panel replacement. Cracked, crumbling or missing panels in a factory-built fireplace replaced with the panel the manufacturer specifies for that model. Panels are never patched.
Firebox rebuild. When most of the lining is loose or the back wall has bowed, the firebrick comes out and goes back in new, tied into the smoke chamber above. Cure time before the first fire is put in writing.
Lintel and throat repair. A rusted or sagging steel lintel over the opening, or a cracked throat between the firebox and the damper, repaired alongside the lining.
Hearth repair. Cracked hearth firebrick or a loose inner hearth, which takes the same heat as the walls.
Smoke chamber and above. The firebox ends at the damper. Cracks that continue up into the smoke chamber get their own repair; see smoke chamber repair. For the rest of the fireplace, from doors to gas logs, start at fireplace repair in Arlington.
How a Firebox Repair Works
- Free estimate visit. We clean the ash out so every joint shows, check each brick and panel, test the mortar with a probe, and look at the lintel, throat and the chase cover or crown that may be letting water in.
- Photos and a plain answer. Which cracks are surface, which need repair now, and whether this is a repoint, a few bricks, panels or a rebuild.
- Written price. Itemized, with the cure time and the first-fire date. If the chimney above needs work to stop water, it is on the same estimate.
- The repair. Drop cloths down, HEPA vacuum running. Masonry repairs use refractory mortar and firebrick only. Panels go in with the clips and gaskets the manufacturer calls for.
- Cure and first fire. Refractory mortar needs days to cure, then small fires to temper. We put the schedule in writing so you do not crack a fresh repair with a roaring fire on day one.
- Final photos. Before and after, for your records and for the next inspection.
Most firebox repairs in Arlington are done in one visit. A rebuild takes two, and we schedule the second around the cure time so the lining sets before it ever sees a flame.
What Firebox Repair Costs in Arlington, TX
Firebox repair runs from a small repointing job to a full rebuild. These are the published reference ranges; Crownline quotes every firebox in writing after the inspection.
| Repair | Typical range (source) |
|---|---|
| Firebox repair, overall | $160–$2,500 (HomeAdvisor, June 2026) |
| Mortar joint repair | $200–$900 (Fixr, 2025) |
| Metal firebox repair | $150–$800 (Fixr, 2025) |
| Refractory panel replacement | $200–$300 per panel with labor (HomeAdvisor, June 2026); $100–$300 per panel (Fixr, 2025) |
| Masonry firebox rebuild | Up to $2,500 (HomeAdvisor, June 2026) |
What moves the price in Arlington: how many bricks or panels are involved, whether the panels for your factory-built model are still made, whether the lintel or throat needs work, and whether a cracked crown or a rusted chase cover upstairs is the reason the firebox failed. Fixing the firebox without fixing the water source means doing it again in three years, so we quote both. Seniors get 10% off, veterans and first responders get 10% off, and we match written quotes from insured companies. One discount per job.
Why Arlington Fireboxes Fail
Heat cycles. Every fire expands the brick and mortar; every cooling contracts it. Sixty years of that opens joints.
Water. Rain down an uncapped flue, a cracked crown, or a rusted chase cover puts water on hot brick and steel. In a masonry firebox it washes out mortar; in a factory-built unit it rusts the floor and the steel behind the panels. We fix the chimney chase cover or crown at the same time, or the repair does not last.
Clay soil. North Texas clay swells when wet and shrinks when dry, and the chimney moves with it. The firebox, tied to a foundation that is moving, cracks at the joints.
Spring storms and freeze-thaw swings. Tarrant County hail cracks crowns and dents chase covers every spring, and the few hard freezes each winter open those cracks wider. The water shows up in the firebox by fall.
Wrong mortar. A past repair with ordinary mortar or hardware-store cement fails in a season. Firebox joints need refractory mortar.
Hot, fast fires. Roaring fires with too much wood, or burning trash and treated lumber, overheat the lining. A cracked panel in a two-year-old prefab fireplace is usually this.
Firebox Repair Is One Piece of the Fireplace and Chimney
A firebox rarely fails on its own, so our technician will inspect around your fireplace as well as inside it. Firebox repair sits inside the fireplace and chimney services in Arlington that one Crownline crew provides. Water that ruined the lining came through the crown, cap or chase cover, which is chimney repair. Smoke and odor after the repair point to the flue, which is a chimney cleaning. Soot on the firebox walls and fireplace glass is a fireplace cleaning. Ignition issues on a gas unit, a pilot or burner that will not light, are gas fireplace repair, and the service call is free. Dryer vent cleaning is $89 while we are in the house. One crew, one written quote before any work begins, and you pick a service or all of them; we lay out the best options and you decide.
Our fireplace repair services cover every Arlington home throughout Arlington, in ZIP codes 76001, 76006, 76010, 76012, 76013, 76016, 76017 and 76018, from downtown Arlington and the homes near AT&T Stadium to South Arlington, East Arlington, Lake Arlington, Viridian, Dalworthington Gardens and Pantego, the towns inside and near Arlington. We are on the Arlington side of Dallas-Fort Worth, not a DFW-wide dispatcher.
Firebox Safety: Why We Do Not Say “Wait Until Spring”
A firebox is a fire inside a wood-framed house. Gaps in it are how heat reaches the framing. The U.S. Fire Administration’s home heating fire guidance reports that heating fires were the second leading cause of home fires in 2021 and asks homeowners to have heating equipment and chimneys cleaned and inspected every year by a professional. The firebox check is the first item on every Crownline inspection, and the dime test is the rule: a crack a dime fits into on edge gets repaired before the next fire. Catching firebox issues early is the cheapest way to reduce fire risk and protect your home that a homeowner can buy.
Why Arlington Homeowners Call Crownline for Firebox Repair
Crownline Chimney Sweep is the local chimney company Arlington homeowners trust for firebox work because we are a masonry crew as much as a chimney crew.
- 20+ years in Arlington homes. We know which 1960s fireboxes were laid in soft mortar and which 1990s prefab models still have panels available.
- Insured and bonded. Proof before we start.
- Free estimate, written price. Repoint, replace or rebuild, you see the number first.
- Right materials. Refractory mortar and firebrick in masonry fireboxes, manufacturer panels in factory-built ones.
- Water source fixed too. Crown, cap and chase cover checked on every firebox job, because that is where the damage starts.
- Discounts. 10% seniors, 10% veterans and first responders, price match on written quotes. One discount per job.
Firebox repair is one of the fireplace services Crownline offers in Arlington, TX. For the brick and mortar outside the house, see chimney masonry and tuckpointing; if the whole factory-built unit is past saving, see fireplace installation. Not sure what you are looking at? Book a fireplace inspection and we photograph every joint. Call (817) 505-4222 or send the form below.
The frequently asked questions below are what Arlington homeowners ask us most about firebox repair, the repair process and what it costs. The FAQ cannot cover everything, so call if yours is not here. For professional fireplace repair Arlington wide, firebox, damper, doors and gas logs, start at the fireplace repair page linked above.