NYC Renovation Chronicles

NYC Renovation Chronicles: Preparing for surprises, costly and not

By David Katz, Architect  | March 17, 2011 - 10:40AM

Every renovation project has its own surprises. Hidden structural columns, pipes in unexpected places, long-forgotten wall finishes, the occasional extra pocket of space—renovations by nature are unpredictable, so it would be unusual not to find something,

Some surprises are merely interesting, providing information about a building’s history. The renovation of a space in a chi-chi Soho building dating to 1805 yielded a big, rusted pair of cutting shears and a few antique apothecary bottles buried between the wall joists. It turned out that the space had once belonged to a barber whose shop was next door.

Less interesting are the surprises that affect your renovation budget. Doing your homework--speaking with the super, making probes in the walls, finding out if anyone in the building did what you want to do--can prevent a number of costly shockers. But even the best foresight and preparation can't preempt every problematic find. I always advise my clients to assume a contingency of 5 percent of the construction cost to deal with situations like these:

Chimney defects

Chimneys are often full of surprises that need to be addressed.  One client, for example, had his fireplace flue examined after neighbors complained of an acrid smell every time a fire was lit. He learned that his flue had been blocked years earlier with a combination of wood and foam rubber. Apparently aware of the blockage, a subsequent occupant had busted a hole into the neighbor’s chimney to vent his smoke. Unfortunately, the resident who discovered this was the one who had to pay a few grand to correct the damage. 

Asbestos insulation

The discovery of asbestos is always an unhappy moment. If your renovation is in a building more than 40 years old, there is a reasonable chance that the common plumbing pipes will be insulated with asbestos.

Therefore, if you plan on doing work that substantially affects the building’s plumbing risers or branch lines hidden in the walls, be prepared for the time consuming and expensive asbestos abatement procedures mandated by law. Work of this type can be undertaken only by companies licensed to do so. Special permits and safety precautions are required: The air must be monitored, for example, and all openings sealed; no one may enter the site while the removal is underway. All this will add a few weeks to your renovation.

Walls, floors and ceilings with secrets

On a job that involved combining two apartments, we opened the ceiling and saw that the old wooden beams had completely rotted away beneath the upstairs neighbor’s bathroom, requiring new steel beams to correct. Then, when the floor was removed, we found that the space above the downstairs neighbor’s ceiling was being used for storing paint. (As an aside, it is best not to store flammable liquids in hidden spaces in wood structures.)  We also discovered that only one gas meter was serving the pair of apartments--so that for years, one of two neighbors had unknowingly footed the gas bills for the other.

Another client of mine was once notified during construction on an adjacent property that his roof was supported by a neighbor’s walls, which were scheduled to be demolished. Whether or not the two properties had belonged to the same owner at one point, no one knew, but the fix—involving structural shoring and steel work to place the roof weight on my client’s property—came at considerable cost solely to him.

Ceilings can harbor happy surprises too: While renovating a parlor-floor apartment in Greenwich Village several years ago, we discovered literally four feet of unobstructed height above a dropped ceiling. In a city with real estate values like ours, that is quite a treasure.

David Katz ( has been practicing architecture in New York City for the last 20 years. Detail oriented, nervous and a little neurotic, he specializes in co-op and condo renovations.

Disclaimer: Information provided herein is not to be construed as professional advice. Readers are urged to consult with a licensed architect regarding their specific circumstances prior to undertaking any renovation work. (We do not want any buildings falling down!)

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