Family-owned smoke chamber repair serving Roosevelt Park

How corbelled chamber walls step inward

In a corbelled chamber, every brick course is stepped inward past the course beneath it. Stacked this way, the courses form a series of small ledges that close the chamber toward the flue. The method is sound masonry, but the inside face ends up rough.

Every ledge is a place for soot, creosote and mortar crumbs to rest. That is why the code asks for corbelled chamber walls to be parged smooth, and why stepped chambers are the usual candidates for parging.

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

Working from the flue down

Those directions begin the coat up high, beside the flue liner, and bring it down toward the damper. Beginning at the top keeps fresh material from dropping onto finished areas below.

Access decides how this happens in each fireplace. Some chambers let us reach the top through the damper opening, while others are easier from above. We explain the route your chamber allows before the job, and it is written into the plan.

Setting the coat thickness wall by wall

Directions for the coating we use allow application from one inch to several inches thick to achieve the desired result. That range matters, because chamber walls are rarely uniform.

A wall with deep steps needs more material to reach an even slope, while a wall that is already close needs less. We set the planned thickness for each wall from what the inspection shows and note it in the estimate, so the plan is visible before the work starts.

Clearing debris from the shelf

A pile on the smoke shelf is more than untidy. Damp debris holds moisture against the masonry, and a large pile can crowd the damper and keep it from closing fully.

We remove everything on the shelf by hand and vacuum before any repair, then look at the surface underneath. If the debris includes old nesting material, we note it, because it tells us something about the cap. Any animal removal is a separate service, quoted on its own line.