So you’ve purchased a Boston brownstone. Brace yourself for the hidden costs renovating a Boston brownstone; the unexpected costs associated with owning this charming relic. These are old buildings and worth preserving their ancient charm. In most cases, you don’t have a choice. The local National Registry of Historic Places has a few requirements. But don’t worry. We’ll prepare you for what’s ahead. Connaughton Construction has been helping property owners for over 30 years get through the journey you are about to embark upon. For historic homeowners who may have a vision of designing your dream brownstone, we’ll discuss a few hurdles to clear. But you’re an optimist. That’s why you’ve chosen a brownstone to renovate, right?

Back Bay Historic District by Connaughton ConstructionAs John Connaughton, the President of Waltham, MA company Connaughton Construction, puts it, while renovation can sound exciting and even fun at the outset, “the cost will be greater than you think, and the process will take longer than you think.” While this is true of most real estate restorations and facelifts, brownstones are special. Here are the unexpected costs to prepare for before you take on your own project, and a few tips to avoid headaches along the way.

Forming the Right team

You want to open up the floorplan or replace the kitchen? Assemble the right team—everyone from the architect, contractor, to the structural engineer. When people get this part wrong, they spend the most money and time on their projects. Brownstone owners on a budget often feel tempted to use companies that charge less because they have less experience renovating historic properties. But trying to save money the wrong way is the most costly mistake to make.

Connaughton’s recommendation to homeowners is, “hire an architect who has experience with other brownstones or historic properties. These projects typically cost around $300 and $400 per square foot,” according to Connaughton. He warns that renovators should be wary of anyone offering a price below $300 per square foot—the experienced architect, who’ll likely charge the higher price, will guarantee to save you future mishaps, wasted money, and time. A qualified architect will also help you recruit the right team. You can check on each individual’s work and references to make sure their clients had a good experience. In the beginning, it’s all about the right professionals, the right process, and the right methodology.

Inspections, Permits, Approvals

If this is your first time renovating in Boston, what surprises new brownstone owners the most is the number of approvals.  This is where the architect and the construction manager are worth their weight. Having them in your corner can deflect a lot of the red tape. They know what and when to submit permits to the Inspectional Services. They’ve made the connections and built relationships with people in the NRHP, DOB, BLC and IS. 

The first step is finding out if your house is on the NRHP National Register of Historic Places. You’ll need permits from the Department of Buildings (DOB) for most interior and exterior work.  The most challenging approvals are changes to the exterior;  doors, windows, masonry, roofing, roof deck, and railings. Brownstones in landmark historic districts need to go through the Boston’s Landmarks Commission. The sooner you reach out to them, the faster you receive approvals for your renovations.

When acquiring a work permit, prepare for the DOB to charge you a nominal fee. A job priced between $100,001 and $150,000 will cost you $1,000 in permitting fees, according to the Landmarks Commission. Boston calculates $10 for every $1000 in renovation costs, or 1% of the construction fees.

Changing Occupancy

 We’ve seen the previous renovation of Boston homes, spend about $9,000 when changing a brownstone’s Occupancy  Changing from a multifamily to a single family. Changing from a single family to 3-family is more involved because it involves zoning changes and goes through the Zoning Board of Appeals. Additional changes such as residential to commercial or vice versa go through the Certificate of Occupancy and zoning changes.

Shoring up the structure

You’ve likely hired an inspector to check out the facade and foundation walls before you purchased your brownstone. If the property has no recent renovations, it’s likely you’ll need to upgrade the structure for modern use. These are old buildings and major structural problems can occur from past changes. If your brownstone was a single-family, then broken up into multi-family units, the structural work often suffers.

Consider the case of a Boston resident we spoke with who’s in the midst of converting a four-family, five-story townhouse into a single-family and needed to replace the beams and the staircase in the process. It’s a high-end renovation, and she and her husband spent about $110,000 to replace the staircase through all five floors with an expensive mahogany—to match the original staircase built in the house—as well as $100,000 for a mix of steel and wood structural beams. Replacing the stairs, a common project for homes that need structural upgrades, can cost upwards of $12,000 for a pre-fab, metal staircase or upwards of $20,000 for a wooden staircase.

Finding asbestos

Finding asbestos is a hot issue and is often associated with unexpected costs during the renovation. The results of an asbestos test, which typically costs around $500, will be required if asbestos is found during demolition. If you find asbestos, the price of removal varies wildly. $10 per square foot is a reasonable ballpark figure.

If your builder finds asbestos in one or two rooms, it won’t be a long project. It is likely you can continue to live in your home. For large-scale removal, it may take a week or longer and might require you to find new lodgings. Typical areas where it may show up include the basement, pipe insulation, and floor tiles. 

Meeting landmark requirements in a historic district

There’s a huge appeal to buy a brownstone in a historic district knowing that the quaint old townhouse next door can’t be demolished and replaced with a sky-high modern condo building. But it’ll also add extra costs, and time if you’re planning exterior renovations. Boston’s Landmarks Commission requires your architect to submit plans for approval before any exterior changes can be made. For minor work, like brownstone repair or window replacement, the BLC will not charge a permit fee. These permits are approved by the commission’s staff and your architect. This is another reason you’ll want to invest in an architect familiar with brownstones. Facade alterations, however, cost a flat fee of $95 for the first $25,000 of work and $5 for each $1,000 worth of work above that, according to the BLC. Significant alterations, like adding an extra floor, will require that your architect makes a presentation to the BLC’s board.

Restoring a brownstone facade to BLC standards requires specialists and can cost anywhere between $20,000 up to six figures depending on the amount of detail and scaffolding required to do the work, according to Connaughton. “It’s time-consuming and labor-intensive work,” he explains, noting that facade carvings will need to be restored by hand. Switching windows to landmarks specification will require new windows to meet the same glass size and details as the ones you are replacing.

Replicating vs Preserving Original Details

People love brownstones, not just for the exterior but oftentimes for the lavish interiors that include stained glass, moldings, woodwork, and fireplaces. Such historic details will play a big part in your budget, according to Connaughton: “With brownstone renovations, there are two ways to go. You can do a complete gut and make it brand new, or you can try to save what you can—and restore the details.”

Connaughton also notes that renovators should be prepared to get creative with historically sensitive renovations, rather than expect to preserve every feature. “Replication versus preservation can be the difference of tens of thousands of dollars,” he says. Take, for example, a fireplace mantle that’s missing some of its corbels or moldings. To restore the fireplace and get new custom-made pieces can be expensive. Owners may instead opt for replacing the fireplace mantel.

Renovation & Demolition Curve Balls

Talk to anybody who’s survived a historic renovation and they’ll tell you to prepare for a few curve balls. Demolition will reveal everything from structural problems to old piping to fire damage that’s been covered up. With the likelihood of surprise, most professionals recommend between a 10 and 15 percent of your renovation budget. 

After renovation starts, we may realize we need to replace the water main, a $10,000 – $15,000 cost. When renovating down to the studs, Boston Fire and the Inspectional Services Department require the installation of sprinkler systems, fire alarms, smoke detectors and carbon monoxide detectors. This can cost up to $60,000, depending on the size of the building. In a very old house, you don’t know what you’ll find. Look at the process as a leap of faith. I’ll be worth it. The payback is great.


Connaughton Construction has over 30 experience renovating historic Boston brownstones. We know how to form the right team, deal with the red tape, asbestos, change in occupancy, and shoring up the structure. Hire the professionals that can make your dream home come true without the nightmare.

Request a FREE Consultation with Connaughton Construction and let the project begin. Design your story with Connaughton Construction.


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If you prefer to talk to someone on the phone, please call John with Connaughton Construction at 781-899-1438 x 14 or  Ellen at x13. You will be glad you did.