Spiraling Down
I built a 60 sq. ft. loft in my studio on the parlor floor of a brownstone in Park Slope. The loft is mainly supported by a spiral staircase in the center, and the co-op is concerned about having so much weight concentrated on such a small area. What are general tolerance levels for brownstone…
I built a 60 sq. ft. loft in my studio on the parlor floor of a brownstone in Park Slope. The loft is mainly supported by a spiral staircase in the center, and the co-op is concerned about having so much weight concentrated on such a small area. What are general tolerance levels for brownstone floors? Does anyone know an engineer who could look at it?
I think so . You can find the solution easly with no problem!!
Regards
Fabrizio
http://www.marmidicarrara.com
I don’t see what the problem is. An engineer can be hired to do a report. That’s what they do. In fact if they won’t do a formal report, why hire them? I can give you a coupla respected engineering firms, pls email me, see my profile.
I would like to agree with you CMU but it’s exactly the formal report part of the issue that I am addressing — OP states that information is needed to settle the issue between himself and his coop. Very different than your getting a quick gut answer from your neighbor (sure that’s done all the time and as you point out totally reasonable), the coop is likely to be seeking a written statement identifying responsibility.
This is a very different situation even from the OP owning the whole brownstone, where this might hardly matter. I don’t even think this is necessarily a safety risk, but certainly the loading condition creates a risk of cracking apart the ceiling plaster in the unit below. Plaster only requires very slight deflection before it cracks alarmingly, even if the structural joists are relatively sound. There have been lawsuits started over far less in our city.
And as an additional point, it’s both true and not true about a brownstone being difficult to calculate loads. Sure brownstone construction is usually straightforward wood joists spaced evenly and spanning the width of the building between masonry walls. Nothing complicated about that. But what I am assuming here is that the building is also 100+ years old, in which case creep and settlement has over the 100 year period created conditions where walls not bearing load gradually become bearing walls. Again not a concern if you have a whole building to yourself, but these 19th century brownstones become fairly intricately tied together structurally in terms of doing work on one floor that doesn’t impact finishes on another floor. That’s what I meant about the complexity of the issue, it’s less a point about safety than creating damage to other floors not owned by the OP.
That might be true, smokeychimp, but it’s a sad statement based on liability issues, not competence.
But your statement about “jerry-rigged condition” is doubtful…if that were true, how would an architect/engineer ever be able to do a renovation plan given the age of our buildings?
There’s nothing about a brownstone that makes it inherently more difficult to calculate loads. Any engineer could easily figure out whether the load was safe or not. And suggest a remedy if not.
In a similar situation, I asked my neighbor, a structural engineer, to look at a deck support and he categorically assured me that it was fine. I accepted his “advice”.
I suggest OP talk with an engineer who’d give him a suggestion w/o a formal report.
I doubt you will find one. Engineers don’t just look at a jerry-rigged condition and take a guess at whether it’s safe, that’s not how they work. To simplify a bit: an engineer analyzes the stresses and reactions involved in loading, and then creates a set of parameters (span, member size, connector type size and quantity, connector detail, etc) to respond to that condition. The parts of the assembly are assumed to be new. The engineer’s instructions then become legally binding documents for a contractor to follow, with procedure for controlled inspections. Even when operating in such a “controlled” scenario the engineer’s professional insurance premiums are staggering and probably their largest cost after payroll and office rent — an engineer accepts legal responsibility for their analysis for good.
So if you do find a good preservation engineer with experience in loading conditions for brownstones (and there are good ones out there), it’s unlikely that they would issue a formal report or document that would be useful in a decision between you and a coop board. Unless they could determine the exact conditions of the loads and connections in your setup, no engineer worth his or her salt will come up with a guess and then accept that liability.
Really, who would want to take over the responsibility for an amateur-built point load in the center of a span of a hundred year old framed floor, constructed without permits?