Michael Stern

By Michael Stern, JDS Development Group The question an architect asks me first about the base of a tower is why so much of it goes to cars. On a site where the rules require parking, the number of spaces is fixed before the plan is drawn, and a number of spaces is a volume of building with a geometry of its own. This is written for the developers, architects and planners who have to decide what the bottom of a building must be before they can decide what it might be. A parking space stops being a number the moment it reaches a drawing. It becomes a stall of a given size, reached by an aisle of a given width, served by a ramp at a slope a car can climb, under a structure with the headroom a vehicle needs and a floor to floor height no apartment would ever ask for. Where the rules require parking, the requirement attaches to the residences on the zoning lot and is written as a count. That count is the first fixed quantity on many sites. Floor area can be moved, massing can be argued...

By Michael Stern, JDS Development Group 111 West 57th Street and The Brooklyn Tower both have to answer the same question, and the question has nothing to do with how either one looks. It is what the building actually does in wind once it is finished, occupied and standing in weather that no model produced. This is written for structural engineers, for wind consultants, and for the developers who end up paying for the instruments that answer it. The first is the tallest and most slender residential building in the Western Hemisphere, built in the courtyard of the landmarked Steinway Hall and designed by SHoP Architects. The second is Brooklyn's first supertall, rising out of the landmark Dime Savings Bank. One is a needle threaded into a constrained site and the other grows up out of a masonry banking hall, and those two starting conditions hand the wind two very different objects to push on. Measuring a scale model in a wind tunnel has been the accepted basis for tall building...

By Michael Stern, JDS Development Group A steel column standing inside an old building usually carries nothing on it that says what it is made of. The mill that rolled it worked to its own practice, the drawings that specified it have often not survived, and the strength of the metal is a question rather than a recorded fact. This is written for the developers, structural engineers and preservation consultants who have to decide what that column may be asked to carry before a conversion is drawn. Why Old Structural Material Has No Reliable Paper Record Structural steel and structural masonry were in heavy use before the trades that made them agreed on common grades and common ways of describing them. A mill sold what its own furnaces produced, a brick came from whichever yard was close enough to cart from, and the building that resulted was a record of local supply in a particular year. Two columns on two floors of the same frame can be different metal. Masonry is worse in this re...

By Michael Stern, JDS Development Group Photo by Gio L on Unsplash A shop drawing comes back from a fabricator with a note in the corner saying the radius shown can be held on three of the four unit types and not on the fourth. That one sentence decides more about a facade than the elevation it was submitted against. On a building with few precedents it usually arrives before anyone has agreed what the building will finally look like. This is written for developers and architects working on buildings whose assemblies no product line already answers. The note records the boundary of what one particular shop can make. That boundary is the governing constraint on the piece, and it appears nowhere in the drawings the design team produced. What a Shop Drawing Actually Governs A shop drawing is produced by the company that will make the thing. The architect draws intent, dimension and performance, and the fabricator draws the object that will exist, including its joints, its tolerances...

By Michael Stern, JDS Development Group Photo by Julien Riedel on Unsplash A lot I looked at recently carried a base district designation that anyone could read off the public zoning map in a few seconds. The rules that actually governed what could be built there took a zoning consultant the better part of a month to assemble. The designation was accurate, and it was also the smallest part of the answer. A special district had been drawn over that block, a contextual rule governed the street wall along one frontage, and the lot carried a designation that no district color on any map records. This piece is for developers, architects and land use professionals who have to decide whether a site is worth a full analysis before anyone has paid for one. What the base district on the map actually decides The base district is the layer everyone starts from because it is the layer the map is drawn to show. It sets the broad quantities: how much floor area the lot may hold, what uses are p...

By Michael Stern, JDS Development Group Photo by C Cai on Unsplash The question arrives early and it is always put the same way. Can we get the column out of the corner. On a narrow floor plate that question is the plan rather than a detail of it, because the corner is where the rooms want glass on two sides and where the structure wants something solid. This is written for architects, structural engineers and developers working on footprints small enough that the answer changes the building. The honest answer takes a few minutes to give properly. It starts with what the column is actually holding. What a Corner Column Is Actually Holding Under gravity alone the corner column is the least consequential column on the perimeter. It collects load from a quarter of a bay where an interior column collects a full one, and on that arithmetic it looks like the easiest thing on the floor to delete. Under wind it is doing something else. A tall building resists overturning by pushing down...

By Michael Stern, JDS Development Group Put two of our buildings beside each other on a single variable, which is how much of the new work a person standing on the sidewalk can actually see. The Brooklyn Tower rises from the landmark Dime Savings Bank, and everything added there is visible from several neighborhoods away. Walker Tower is a Ralph Walker Art Deco telephone building conversion that added roughly 50,000 square feet, and almost none of that area announces itself to someone on the street below. That difference is not a matter of taste. On a designated building, new work above the existing roof is reviewed for what can be seen from the public way, so the shape of a rooftop addition is generated by lines of sight rather than by the floor plate that wants the area. This is for developers looking at a designated building with unused area above it, and for the architects and preservation consultants who will have to draw the thing. What a Rooftop Addition Is Measured Agai...