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Lords Chimney - Chimney Sweep and Fireplace Vent Service
Lords Chimney - Chimney Sweep and Fireplace Vent Service
Look closely and pay attention to the signs that say your firebox needs a replacement.

Look closely and pay attention to the signs that say your firebox needs a replacement.

Before we talk about firebox replacement , let’s get into what a firebox is. When you stack up your wood and build your fire in your fireplace, the area that’s holding that fire — fittingly, shaped a lot like a box — is what we refer to as the firebox.

Whether you have a masonry or factory-built fireplace, that firebox was made with materials that were designed to hold up to years of high heat (and since the firebox really does bear the brunt of the heat of your fire, they need to be built that way). Masonry fireboxes are constructed out of firebrick, and those firebricks are made with a refractory material that’s highly resilient when exposed to extreme temperatures. Factory-built or prefabricated fireplaces are largely built out of metal, but the firebox itself is bolstered by refractory panels on the bottom and sides — which also offer that durability and strength when faced with the high temperatures of repeated fires.

Why Would I Need To Replace A Firebox?

As strong as fireboxes are designed to be, over time, it’s not unusual for damage to occur. The type of damage will differ, depending on your individual use, circumstances, the firebox’s construction and other factors, but we see a few common problems.

Masonry fireboxes

Sometimes masonry fireboxes weren’t built correctly (with older ones, it’s not uncommon to see non-refractory mortar that just isn’t equipped to last under that abuse). Sometimes leaky chimneys allow water to get into the firebox, and as moisture combines with creosote, acids start to wear at the masonry — particularly the joints. If the damage is serious, you may notice it as you go to build a fire. But more likely, it’ll take professional eyes to see a problem in your firebox — and firebox problems can quickly become fire hazards, so that underlines why annual chimney inspections are so important.

Factory-built fireboxes

Most often, firebox refractory panels just begin to wear and abrade, and cracks start to develop either in the panel itself or around the joints between panels. A good rule of thumb is generally to seek repairs or replacement when cracks reach the thickness of a nickel.

The repair approach will depend, too, on the individual circumstances of the firebox and its damage, and Lords Chimney technicians will fully inspect yours to recommend the best course of action. Sometimes refractory panels can be replaced to repair a factory-built firebox. Sometimes the firebox has reached the end of its service life, and the unit needs to be replaced. We may be able to repair damaged mortar joints in a masonry firebox, or it may need to be rebuilt. But rest assured, when you have Lords Chimney come out to take care of your firebox problem, your fireplace will get the attention it needs, and you’ll get back the heating appliance you love, returned to the levels of performance and safety you expect.

If you have any questions about fireboxes — or your firebox, specifically — we’re always here to help. Just give Lords Chimney a call!