John in, Lou Schaff
25,199 8As the recent collapse of the front part of a building on Madison Avenue and 55 Street, and other events around the city, suggest that problems with construction and weathering can cause brick to fall off the main part of the structure.
Due to the recent accident, the city appears ready to strengthen the facade inspection requirements and extend it to the entire exterior of the building, not just the part overlooking the sidewalk.
This in turn prompted some property managers to use new technologies to measure the condition of brick facades more accurately.
Fiber optic devices can observe the interior of the wall through relatively small holes, so there is no need to cut the entire part, and the laser measuring system can produce accurate written and visual reports on the location, over time, the position of each part of the brick in the facade changes.
If the bricks appear to be in a different position during subsequent inspections, managers have reason to suspect that something is wrong.
Engineers say the brick facade of modern building space is one to 2 inch away from the main structure of the building, adding a layer of insulating air
Pane storm window.
Although the advertisement looks from the outside that the brick wall is continuous from the bottom up, there is actually a steel shelf on each floor, explained Anthony pagonota, an engineer at HLW International, so the bricks at the bottom don't have to bear a higher weight, a New York Construction Engineering Company.
In order to link bricks to the main structure of the building, brick layers should use thousands of metal bars called Wall bricks, fix them in buildings, and insert mortar that combines individual bricks together.
It's a good practice to use a tie on other brick paths about 6 inch apart vertically and horizontally, SirPagnotta said.
City officials said it was the lack of these connections that caused the facade of a building at 540 Madison Avenue to partially collapse at the end of last year.
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But other things can go wrong, most of which involve water.
If the rain penetrates between the bricks and gathers in the air gap, the Wall bond and the support frame corrupts and destroys the stability of the facade.
City regulations require landlords to hire a qualified architect or engineer to conduct a visual inspection of the front of a building above six floors and the side walls of the top 20 feet.
They will look for signs of cracking, rust and other pain.
But some managers say they want to get an earlier warning to make repairs before the problem spreads and becomes more expensive.
Bill Porceller, manager of Sage real Corporation, said: "any property manager who relies on city minimum checks is crazy . ".
He said that a laser measurement would produce a report that would position the brick facade in-
16-inch, more accurate than visual inspection.
Others say that when trouble has developed, detailed checks on the opposite side are the most economical.
John Santara, senior general manager at Kushman & Wakefield, said: "Laser is a great technology, but it's better to use it when you have a problem . " It manages 60 million square feet of property in the metropolitan area of New York.
Lon Best, president of one of the Best contracting companies specializing in facade maintenance, said that in one inspection, the laser light source was installed near the brick wall and a vertical light wall parallel to the wall was emitted.
With this, the worker on the scaffold placed the instrument directly on the laser beam and measured it from there with a ruler to the surface of the brick.
With this information and follow-up
After checking, the building manager or owner can decide whether the part of the wall moves because of deterioration, or whether the ups and downs on the wall are the result of the original building, as they do not change year by year. Mr.
Best said it plans to repair $4 million on 425 Park Avenue on 55 th Street due to a laser survey and was cut to $360,000.
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A version of this article was printed on page B00006 of the National edition on February 25, 1998, with the title: commercial real estate;
A new diagnosis of the building facade.