Cracked firebrick, gaps where the mortar used to be, a firebox that has taken a lot of winters. We rebuild the part of the fireplace that keeps the fire off your house.
Those brick walls around the fire are the one thing standing between a live flame and the wood frame of your house. When the brick cracks and the joints wash out, heat starts reaching places it was never meant to. That is why a firebox in rough shape is worth handling before the next fire, not after.
A wood-burning firebox is built from firebrick set in heat-rated mortar, and its only job is to hold the fire in and keep that heat away from the framing behind it.
Every fire you light puts the brick through a hard cycle. It goes from room temperature to several hundred degrees and back again in a few hours. Do that a few hundred times and the brick expands and shrinks until it cracks, and the mortar in the joints slowly loses its grip.
Plenty of the fireplaces we see in LA sat mostly for looks for years. Then a cold week rolls through, the family burns wood every night, and a firebox that already had hairline cracks gets pushed hard. That is often when the gaps open up enough to notice.
What we look at is simple to describe. Is the firebrick sound, are the joints between the bricks still full, and is the heat staying where it belongs. When one of those has gone, we rebuild that part with the right materials instead of dressing it up.
None of this is about how the fireplace looks from the couch. A firebox can read fine across the room and still have a crack running back toward the framing. It gets checked up close for a reason.
Tell us what the firebox looks like when you call. It usually points to what needs doing before we get there.
The back wall takes the most heat, so it is where cracks tend to start. A fine line that stays put is one thing. A crack you can slip a coin into is a path for heat to reach whatever sits behind the wall.
Depending on how many bricks are involved, we replace the cracked ones or relay the back wall. The brick has to be actual firebrick, rated for the heat, not a face brick that looks close.
The thin lines of mortar between the firebricks are the first thing to go. Heat and old age turn them to powder, and pieces drop out until you can see straight into the gap.
Once the joints are open, the fire has a way past the brick. We rake the old material out and repoint the joints with refractory mortar, which is the part people most often get wrong on their own.
If your fireplace is a prefab metal unit rather than full masonry, the inside is lined with refractory panels instead of brick. Those panels crack from heat the same way brick does.
Once a panel has a crack wider than a matchstick, the manufacturer wants it swapped. We match the panel to the unit and replace it so the steel body behind it stays protected.
The damper sits just above the firebox and opens to let smoke out. Years of moisture and heat rust it until it sticks halfway or will not close at all.
A stuck-open damper lets your heated air pour up the flue all winter. We free it, rebuild the seat, or fit a new damper depending on what is left to work with.
Above the damper is the smoke chamber, a funnel that gathers smoke and sends it up the flue. It is meant to be coated smooth so soot does not catch and smoke moves freely.
On older fireplaces that coating is often rough or missing, which slows the draft and lets creosote build in the corners. Parging it smooth helps the fireplace pull the way it should.
This is the mistake we clean up after more than any other. Someone notices the joints in their firebox crumbling, buys a tub of mortar from the hardware store, and packs it in. It looks solid for a week.
Then the first few fires cook it. Standard masonry mortar is not made for direct flame, so it dries out, cracks and drops right back out, sometimes worse than before. The gap is open again and the fire is still finding its way past the brick.
A firebox needs refractory mortar and firebrick, both rated to hold up near 2000 degrees. We build it with those, because a joint that fails in a month is not a repair, it just hides the problem until the next cold night. The materials are the whole reason a proper firebox rebuild lasts.
A firebox that lets heat through does not fail quietly. It works on the framing behind it fire after fire, and that is the kind of damage worth getting ahead of.
Most of the call is figuring out how far the wear has gone. The repair itself follows from that.
Cracks in the brick, joints falling out, a damper that sticks, a panel that split. Whatever caught your eye helps us bring the right materials.
Brick, joints, floor, damper and the smoke chamber above. We work out which parts are still sound and which have to be redone.
What is worn, what it takes to fix, and the number. Nothing starts until you have said yes to it.
Firebrick and refractory mortar for masonry, matched panels for a prefab. Whatever it needs, it goes back with the materials meant for the heat.
Refractory mortar needs time to set before its first fire. We tell you how long to wait so the fresh work is not cooked green.
It depends on the crack. A fine surface line that has not moved is usually fine to keep an eye on. A crack you can fit a coin into, or one that runs deep toward the back wall, gives heat a path toward the framing, and that one should be handled before you burn again. We can tell you which kind you have once we see it.
Often a patch or a few replaced bricks is all it takes. When the back wall has cracks in several bricks, or the joints have washed out across the whole firebox, a relay lasts far longer than chasing one crack at a time. We give you the honest version after we look, not a rebuild quote for a two-brick problem.
Regular masonry mortar is made for walls and holds up to weather, not to flame. Put it in a firebox and the heat dries it out and cracks it apart within a few fires. Refractory mortar is rated to hold near 2000 degrees, so it stays put where the fire actually touches. It is the single most common thing homeowners get wrong doing this themselves.
Yes. Factory-built fireplaces use refractory panels instead of brick, and those are meant to be swapped when they crack. We match the panel to your make and model so the steel body behind it stays protected. If the unit is old enough that panels are no longer made for it, we will tell you that too.
Two likely reasons. Either it was patched with the wrong mortar and the heat keeps knocking it loose, or the joints are just old and worn from years of fires. Raking them out and repointing with refractory mortar is what actually holds. A quick smear over the top of a bad joint never lasts.
It comes down to how much of the firebox needs work. A damper freed up or a few bricks replaced sits at the low end. A full firebox relay or a panel replacement on a prefab runs higher. We look first, then give you the number before any work starts, so there is no guessing partway through.
We would hold off until it is checked. A cracked firebox or an open joint can let heat reach the wood frame around the fireplace, and that is exactly the kind of thing that does not announce itself until it is a real problem. Have it looked at first, and if it is minor you will know that quickly.
Tell us what the firebrick and joints look like and we will tell you where it stands. Findings first, price before we start, and a repair built with the right materials.
