Smoke chamber repair in LaVina

The throat between firebox and chamber

Smoke leaves the firebox through the throat, a pinched opening that leads into the chamber. Section R1001.7 places the throat or damper at least 8 inches above the lintel over the fireplace opening.

Throat masonry takes direct heat and holds the damper in many fireplaces. Broken mortar, a displaced brick or an old patch at the throat can narrow the passage and give a new chamber coat a poor place to start. We repair the throat first when it needs it, then build the chamber finish above it.

What open joints do to the chamber wall

Mortar joints inside a chamber are exposed to heat, moisture and acidic deposits every time the fireplace is used. Over the years, some of that mortar can erode and leave open channels between bricks.

An open joint is a short path for heat and gases into the wall. It also gives deposits a place to lodge where a brush cannot reach. We rake out loose material, fill the joints with refractory mortar and then parge, so the wall is sealed and smooth from the throat to the flue.

• Heat reaches deeper into the wall
• Deposits lodge out of brush reach
• Loose mortar falls onto the damper

Small fires for the first days

After the conditioning fire, the maker advises keeping fires small for an additional five days as a precaution, since excessive temperatures could create steam if any moisture is still present in the repair.

That means no big weekend fire right after a chamber job. We tell you the date when normal use can resume and are happy to answer questions during that week. It is a short wait for a coat meant to serve for many years.

Firebox repairs listed apart from the chamber

The firebox below the damper takes direct flame and has its own wear, from cracked firebrick to eroded joints. When a chamber job reveals firebox damage, it is written up as firebox repair, a separate item.

Doing both on one visit can save time, since the room is already protected and the fireplace is out of use for curing anyway. We price each part on its own, so you can see the chamber cost clearly and add the firebox work only if you want it.

Masking the fireplace face and hearth

Cured coating is hard to remove. The data sheet we work from warns that once the material cures, it will damage any non-target surfaces, and it calls for inadvertent spray or spills to be cleaned at once with warm water and mild detergent.

That is why we mask the fireplace face, the surround and the hearth before mixing begins. Stone, tile and painted brick near the opening get extra care. Any splash is cleaned right away, before it has a chance to set.