How Do You Restore a Brownstone Chimney in Back Bay?

What restoration means on a rowhouse chimney

Restoration is not the same as replacement. The goal is to keep as much sound original material as possible and fix only the parts that have stopped doing their job. On an older rowhouse that usually means a handful of small, targeted repairs instead of one big rebuild.

A restoration scope is made of separate pieces, and each one should get its own line in a written quote:

• Joints where old mortar has eroded and must be raked out and refilled.
• Individual bricks that have flaked or split and need to be cut out and replaced.
• The crown, the cement slab on top of the stack, which cracks and lets water in.
• The cap over the flue, which keeps rain and animals out.
• The flashing where the chimney meets the roof.

Because the work is detailed, it is closer to masonry repair than to a quick patch. A restoration quote that is one lump sum with no breakdown should make you ask questions.

Tight rooflines and shared walls: planning access

Many Back Bay style rowhouses sit shoulder to shoulder, so a chimney may stand a few feet from a neighbor's roof or rise from a party wall. That changes how a job is planned long before any brick is touched.

Get these questions answered before a start date is set:

1. How will materials reach the roof, and does that route cross a neighbor's property?
2. Does the crew need to work from an adjoining roof or yard, and has permission been arranged?
3. How will the roofing around the chimney be protected from falling mortar and dropped tools?
4. Where will debris be collected and hauled away on a narrow street or alley?

Talk to the neighbors early. A short conversation about noise and access is easier than a job that stops halfway. If your flue sits in a stack that also serves the next house, say so during the inspection so the technician can look at the whole stack and not just your side. Access difficulty is one reason two quotes for the same repair can differ, so ask how it is priced.

Matching old brick and soft mortar

Mortar in a century-old wall was built softer than most modern products. It was meant to be the weaker part, so it wears first and protects the brick. Push a hard modern mortar into those joints and the bricks take the stress instead. Their faces pop off, and the repair makes the damage worse.

Before work begins, ask the contractor:

• What mortar will go into the joints, and why is it suitable for this brick?
• Will the new joints match the width and tooling of the old ones?
• If bricks must be replaced, how closely will the new ones match in size, color and texture?

Appearance matters on a street where the chimney is visible from the sidewalk. A match will not look perfect on day one, because fresh mortar is lighter and blends in as it weathers. For more on joint work, see our page on chimney repointing, and read what crumbling mortar is telling you if you are unsure how serious yours is.

Where older Boston chimneys usually give out

Greater Boston has cold winters, freeze-thaw cycles, salt air near the coast and the occasional nor'easter. Water gets into brick, freezes, expands and pushes the surface off. Older stacks tend to show trouble in the same few places.

The top of the stack

The crown and the top few courses of brick take the most weather. Hairline cracks in the crown let water run down inside the chimney, where you cannot see it from the street.

The roof junction

Flashing is the metal that seals the chimney to the roof. When it lifts or the sealant dries out, water gets in beside the chimney and shows up as a stain on a ceiling or wall below. See chimney repair costs for how these fixes are priced.

Joints facing the weather

The side that takes the wind and driven rain usually erodes first. Sandy, crumbly mortar you can scratch with a key is a common sign.

Unused flues

Old rowhouses often have flues that no longer serve anything. An open, uncapped flue is a path for rain, birds and animals, so it needs a cover even if you never light it.

Historic review: confirm before you change anything

Some Boston neighborhoods have historic districts or similar review bodies, and exterior changes that can be seen from the street may need approval before work starts. Whether your building is covered, and what counts as a change, depends on the property and can be updated over time. We will not guess at it for you, and a neighbor's experience may not match yours.

The sensible order is:

1. Ask your historic commission whether your address is in a reviewed area.
2. Ask your city building department whether the planned work needs a permit.
3. If you live in a condo or a shared-ownership building, check with your association or trust, since the roof and chimney may be common property.
4. Get any answers in writing and pass them to your contractor.

Reviewers often treat a like-for-like repair differently from a change in brick, height or shape, so describe the job clearly when you ask. Do not let a contractor tell you that approval is unnecessary without seeing it from the official source.

What the visit should record and how price follows

A good inspection ends with photos and a written scope. For a restoration job, the technician should record the condition of the joints, any cracked or flaking bricks, the crown, the cap, the flashing and the state of any unused flues. Photos of each problem area let you compare the notes to what you can see yourself.

The $49 general inspection includes findings and recommendations, and the fee is credited toward approved repair work. A second opinion is free if you bring a written report from a reputable local chimney company. Here is how masonry repair is priced in Boston:

Access, height, the number of bricks to replace and roof protection push a job toward the higher end. If the inspection finds something outside these bands, the quote is written after the visit, before any work starts.

A plan for the next few weeks

You do not have to decide everything today. Work in this order and the decisions get easier:

1. Look at the chimney from the street or your window with binoculars. Do not go on the roof. Note leaning, missing bricks, white staining or a cracked top.
2. Check ceilings and walls near the chimney for stains, especially after a heavy rain.
3. Stop using the fireplace if you smell smoke inside, see falling debris or find loose brick pieces in the firebox.
4. Contact your historic commission and building department so approvals do not delay the work.
5. Book an inspection and ask for photos with the written scope.

If you notice a fire in the chimney or house, leave the building and call 911. To have a technician document your brownstone chimney and give you a written price, book the $49 inspection at /contact/ or call (617) 404-9587.

Questions homeowners ask