Look ma, no leaks!

Our building received a new roof and a thorough waterproofing in 2006-2007. These pics show installation of corrugated metal sheets along the brick portion of the roof and elevator and dumbwaiter shafts. Originally coated with a thick black tar, there were too many small leaks that let water into the brickwork (and then down into the apartments). Jon Wickers, owner of a prestigious building restoration firm (who has a long relationship with the co-op) did a complete evaluation to see where our leaks were coming from. He discovered the tar coating actually trapped moisture inside the 2 layers of brick, and designed this system to cover the side and top of the masonry with an aluminum skin.

The first step involved literally slicing into the brickwork to insert a thick sheet of copper flashing. This ensured any water would drip down, hit this and end up on the roof instead of heading down through the entire brick walls of the house. Once this was installed, the bricks were cleaned up and the aluminum skin was mounted.

The historic district required nothing this modern be visible from the street, so the terra-cotta front portion got a thorough, but old-fashioned waterproofing, with sandblasting, re-grouting and pointing.

As you can tell, this job was done in the fall, when the workers won't collapse from the heat! The following spring, a layer of white roofing material was laid down, to complete the job. Air vents were installed to let hot air out, and the original skylights were pronounced good enough to be repaired instead of replaced, thanks to their good old-fashioned thick glass and galvanized steel frames. Unfortunately, the dumbwaiter "mini" skylights were too far gone, and were capped off, leaving our dumbwaiters in the dark for the first time in 80 years. It was a small price to pay for waterproofing, though. The top floor apartment owners were able to throw away their rain buckets and umbrellas, the operation was a success!

You can see the brick dust after a stout saw blade sliced through the tar and a few inches into the bricks. In this slot, the copper flashing was inserted into the wall. The horizontal metal strips will support the new skin.

The cylindrical air vent lets hot air out without a fan, and allows any moisture to escape.

All done, the new white aluminum covering should last a long, long time. Later, white metal caps will cover the top stone "cap" of the brickwork, keeping any water out of our walls.

The elevator shaft receives it's metal walls. As the work was being done, it was noticed that the rain gutter on this structure was mis-placed, and during a storm was directing some water into the air shafts (the arrow shaped appendage) that ventilate the elevator and your sun-room closets. The mystery of how rainwater ended up in the lower floor apartments every now and then was solved!

The stairs to the roof fully encased, even the 4 fireplace flues got the treatment, to keep any water out!

Here's the 'before' shot, with the old layers of bubbling tar shown. Each 'bubble' drained out really old water when they were pierced, this section of the old tar was not removed because it was only covering the chimney flues.
You'd never guess from the street that we have a white energy efficient water repellant roof up here. The terra-cotta on the left was later re-grouted and any chips or cracks sealed with a color-matched stone cement.
The TV antennae were removed from the wall and attached to the plumbing vent, not even a screw or nail was allowed to pierce the buildings new skin. On the ground is the aluminum cap for the old dumbwaiter skylights, which were rusted beyond repair.