Cockroach Control in Greenwich Village

Why does one riser decide the whole building?

Because the building was designed that way, and the design is still doing what it was designed to do.

A tenement plan is an efficiency exercise. On a standard twenty-five-by-hundred-foot lot, the type put four apartments on each floor in railroad layout and stacked the wet rooms of every floor into a single vertical line so one riser could serve the building. That is why an old-law dumbbell could hold three hundred people in eighty-four units, and it is why by the turn of the twentieth century there were roughly eighty-two thousand old-law tenement buildings citywide, more than half of them in Manhattan.

Read as a plumbing diagram, it is sensible. Read as a habitat, it is a purpose-built distribution system.

Every apartment on that line has at least one wall that opens into the riser void — around the waste pipe, behind an escutcheon plate where a supply line enters, under a cabinet toe kick, behind a cabinet back. The clearances involved are measured in millimeters, and a German cockroach is not troubled by that. The void itself is warm, because heating and hot supply share it. It is damp, because a cold line sweats and an old joint weeps and a slow leak inside a boxed chase never reaches a ceiling and never gets reported. And it is never opened, by anybody, for any reason.

So the question a resident asks — why me, when my kitchen is clean — has an answer that has nothing to do with them. The answer is that your flat sits on that riser, and somewhere along it a population is being fed. It may be four floors below. It may be behind a shop at street level. It may be an apartment where somebody has been managing quietly with retail products for two years and has told nobody.

What follows from that is the entire method. Where the insects are exploiting the structure, the scope of work has to match the structure. An apartment treated in isolation is an island in the middle of a habitat.

For the general approach see cockroach control; for the rest of the neighborhood’s stock, pest control in Greenwich Village.

What does a railroad plan change about the work itself?

It removes the room as a unit of containment and spreads the harborage along every wall in the flat.

In a modern apartment the rooms are discrete: a corridor, doors, a kitchen you can close. In a railroad flat the rooms open one into another with no corridor at all, so the kitchen is a through-route between the front of the building and the back. Three consequences follow, and none of them is obvious from a floor plan.

Furniture is pushed to the walls. With rooms functioning as circulation, everything gets pressed against the perimeter to keep the through-route clear. That puts the backs of wardrobes, sofas, bookcases and beds hard against wall surfaces along the entire length of the flat, and each of those contacts is harborage.

There is no containment. A treatment scoped to “the kitchen” in a railroad flat is treating one segment of a continuous space. The insects do not encounter a door on the way out.

Some rooms have no window. Interior rooms in these plans depend on light and air from an adjoining room or from a shaft, which means they run darker, warmer and less ventilated than the rest of the flat. Those are the best rooms in the building from the insect’s point of view and the least likely to be inspected.

The practical version of all this is that treatment in a tenement flat means treating harborage — the void behind and under the cabinetry, the riser penetrations, the appliance recesses, the wall line behind heavy furniture, the hinge and pivot points where insects shelter — rather than the visible surfaces of a kitchen. Spraying a baseboard along a railroad flat achieves very little and disperses what it does reach.

Why does flat-by-flat treatment leave the building infested?

Because pressure on part of a continuous population is a displacement mechanism, not a reduction one.

This is worth stating carefully, because it is counter-intuitive and because it costs small landlords a great deal of money over a decade.

When a treatment reduces numbers in one flat, it does not create a vacuum that stays empty. It reduces competition on that segment of the riser, and where the material used is one the insects can detect, it makes the treated apartment temporarily unattractive. Both effects push individuals along the route. In a tenement, along the route means the apartment above, the apartment below and whatever else the riser reaches. A one-apartment problem has become a three-apartment problem, and there is an invoice proving something was done.

Repeat that monthly, attending to whoever called that month, and the outcome is a stable, permanent, mid-level infestation distributed along the line. The population is never taken below the point at which it recovers between visits, and none of the routes is ever closed. The file shows a great deal of activity and no trend at all. Cornell’s work in multifamily housing puts the general case bluntly: monthly spraying is a poor substitute for prevention and non-chemical control, partly because insects shelter where residue is not, partly because resistance develops, and partly because the method requires the insect to walk across a deposit that is degrading from the day it goes down.

What replaces it is a different unit of work.

Monitor the whole line, including the quiet flats. Small passive monitors in the kitchen and bathroom of every apartment on the riser, plus the cellar, for a defined period, then read. That produces counts by location rather than complaints by resident. Proactive monitoring in multi-unit housing repeatedly finds severe infestations that complaint-driven service never saw, because every unit was examined rather than only the ones that called.

Weight treatment to the source. The apartment with the highest count is where the work matters. Treating six flats evenly is a way of spending a budget without changing an outcome.

Close the route while you have it open. Riser penetrations, escutcheons, cabinet voids, the top and bottom of the chase. This is the only part of the work that changes the building rather than the moment, and it is the same list as under structural exclusion.

Return for the eggs. The female carries the egg case until shortly before hatching, so the nymphs that emerge after the first round are why a single visit never finishes this insect.

What is the cellar contributing, and is it the same insect?

Usually not the same insect, and the distinction changes which trade you need.

Village cellars are shallow, often with soil contact on two sides, under buildings of three to six stories with drainage laid in the nineteenth century for a very different pattern of use. They are damp by construction. That supports a permanent below-grade population that has nothing to do with kitchens.

Oriental cockroaches are the most diagnostic of the group. Dark, sluggish, and reliably associated with standing water and organic sludge: a blocked yard drain, a cellar floor that holds water, a failed floor drain, the ground around a sump.

American cockroaches are large, reddish-brown, and travel drain lines. They can appear in a top-floor bathroom having come up a stack from a cellar, which is why they occasionally turn up in apartments with no local source at all. Where they appear indoors the finding is usually a dry floor drain, a broken drain line or an open cleanout below.

The reason to separate them from the kitchen problem before writing a scope is that the money goes somewhere completely different. A German cockroach problem is answered with monitoring, targeted material in harborage, sealing and access along a line of flats. An Oriental or American problem is answered with drainage repair and moisture correction, and if the drainage is not corrected nothing applied above it will hold. That work overlaps almost entirely with rodent control in Greenwich Village, because the house drain and the cellar line are the same features in both.

One more organism deserves naming because it exploits the same voids and behaves unlike a cockroach: pharaoh ants are an ant, and they are the case where the wrong material makes the problem structurally worse by splitting the colony. Small yellow-brown ants trailing in a bathroom are a different question entirely.

What does a rowhouse cut into flats add to the picture?

A second, retrofitted wet line and a set of penetrations made by whoever was cheapest at the time.

A large share of the Village’s apartments are not in purpose-built tenements at all. They are in Federal and Greek Revival rowhouses built for one household, later subdivided — sometimes into two flats, sometimes into five, sometimes with a commercial floor at the bottom. Some have been converted, reconverted and converted again as the building went from residential to commercial to institutional and back.

Every one of those conversions cut new holes through floors and party walls, and closed them to whatever standard the trade of the day thought sufficient. That produces a different geometry from the tenement.

The stack runs where it could. In a purpose-built tenement the riser is where the plan says. In a converted house it went wherever the joists allowed and wherever it could reach the house drain, which means it can be in a corner, in a boxed-out closet, in furring against a party wall, or in three different places on three different floors.

There are usually several generations of it. A house converted after the war, reconfigured in the eighties and altered again this century has three sets of penetrations, each cut through the previous set’s closures.

The party wall is in play. Where a retrofitted stack was run against a shared party wall, the joist pockets in that wall — never closed on nineteenth-century construction — connect the chase to the building next door.

Finding it is a physical exercise. Start at the house drain in the cellar, because every riser lands there, and follow what leaves it upward. Then look for the boxing: furring, a built closet, a fabricated bulkhead. Those are almost always open at the top and the bottom, because the trade that built them was hiding a pipe rather than closing a cavity.

Does the old air shaft carry this insect as well?

Where it was closed up, yes — and it is the route people never think to look at.

The 1879 Act required every habitable room to have a window on plain air, and the dumbbell plan answered it by indenting the sides of the building to form a shaft between adjoining structures, in some cases as little as twenty-eight inches wide. It was a poor shaft. The 1901 Act abolished the type, but the buildings remained, and over the following century a great many of those shafts were roofed over, floored across at a level or two, built against by an adjoining development, or closed during a renovation because they were doing nothing.

A closed shaft is a better habitat than an open one. It is inside the thermal envelope now, so it is warm. It is undisturbed, because there is no reason to open it. It is shared between two separately owned buildings. And it has openings into it at every floor: the old window reveals, which were rarely properly blocked, plus every pipe and cable that has been run through it since somebody realized it made a convenient vertical route.

That last point is the one that matters here. Where a closed air shaft has been used as a services chase — and in this stock it very often has — it is functionally a second riser, serving a different set of rooms from the first one, with no plan recording it. A building that has monitored its wet line thoroughly and found the counts do not explain the pattern is a building that should be looking for the shaft.

The same is true of dumbwaiter shafts, which survive behind panelling or inside cupboards on each landing far more often than owners realize, and which connect the cellar to the top floor without passing through a single occupied room.

What does a bar or a restaurant downstairs add?

A commercial kitchen’s worth of warmth, grease, waste and standing water, connected to the apartments above by the drainage and risers they share.

The Village’s commercial corridors run through its residential fabric rather than beside it. Bleecker, MacDougal, Christopher, Greenwich Avenue and the avenue cuts carry a dense concentration of food service at street level, in buildings whose upper floors are flats. The mechanism is unremarkable: a population fed in a prep or dishwash area at ground level travels the same vertical lines that serve the kitchens above, and a residential complaint on the second floor is a commercial question until it is ruled out.

What makes this harder in the Village than in a large mixed-use building is scale and authority. In a twelve-flat building over a restaurant, the residential owner may be one person, the commercial tenant may operate late into the night, and the waste of both goes out onto the same short stretch of sidewalk. There is no managing agent to convene anybody.

Three things help.

Survey the whole vertical section or say honestly that you have not. A proposal that stops at the ground-floor ceiling cannot see the source, and it should say so rather than implying otherwise.

Get the tenancy onto a program built for a food premises. That is what the commercial program and, specifically, restaurant pest control are for, and it is a different discipline from residential work rather than the same work at a different address.

Fix the slab between them. Collaring the penetrations where plumbing crosses from the commercial floor to the first residential one is the single highest-value repair in a building of this kind, and it is usually a day’s work.

How does an owner get access in a building with no managing agent?

By making it routine before it is urgent, because in a small building there is nobody whose job it is to insist.

This is where these programs fail in the Village far more often than they fail technically. A tenement or converted house with four apartments has no superintendent, no managing agent and no house rules that anyone has read. When a case arrives, the owner is negotiating access with people who are simultaneously their tenants and their neighbors, at a moment when everyone is embarrassed.

Access rights and notice practice come from the lease and from law, and that is a question for counsel rather than for a technician. But four things are within any owner’s gift and all of them help.

Write a routine access and notice practice into tenancies before you need it, framed as maintenance rather than as an accusation.

Make it explicit that reporting is confidential. A tenant who fears being identified to the neighbors does not report, and silence is the single most expensive thing that can happen to a building with this insect.

Do not make the neighbor pay to be cleared. Inspecting the flats either side of a reported case is the building’s cost, not the tenant’s, and charging for it produces refusals.

Ask what has already been used. Retail products change where the population has gone. Disclosure is diagnostic, not embarrassing, and treating it as embarrassing costs you the information.

The duties behind this sit with the owner. Once a building is arranged for three or more independent households it is ordinarily a multiple dwelling, and the Housing Maintenance Code puts the obligation to keep the premises free of insects and other pests on the owner — NYC Housing Maintenance Code — extermination and rodent eradication. Local Law 55 treats cockroach infestation as an indoor allergen hazard and adds periodic investigation, remediation by integrated pest management and sealing in durable materials, and says directly that pesticide use does not substitute for those measures. Anyone letting apartments should read landlord and tenant pest responsibilities; it catches a great many Village owners who have never thought of themselves as landlords.

What has to be repaired rather than sprayed?

A short list, done once, that a small owner can actually budget.

Riser penetrations at every floor, closed in material that cannot be gnawed or pushed past.

The top and bottom of the chase. A chase closed at both ends stops being a vertical corridor.

Escutcheons, cabinet backs and toe kicks, fitted and closed rather than resting loose against a wall.

The leaks. A weeping joint in a chase, a sweating cold line in uninsulated boxing, a drip under a sink. Moisture inside a heated cavity decides whether a population survives between visits or dies away.

The cellar drainage. Where the below-grade species are present this is the whole job: a floor drain that holds water, a repaired house drain, a cleanout with its cover on.

Party-wall pockets, whenever a ceiling or wall face is open. They can only be closed at that moment, so it is worth remembering during any renovation in the building.

Door sweeps closing gaps to no more than a quarter of an inch — sensible practice and the standard the law sets.

Applications in a residence must be made by an applicator licensed by the state (NYS pesticide applicator requirements), and in a multiple dwelling they carry notification duties (Local Law 36 pesticide notification, the New York neighbor notification law). Boards of converted buildings should read co-op and condo board obligations; anyone comparing proposals, choosing a pest control contractor.

For comparison, SoHo shows the same insect in a converted loft with a commercial ground floor — cockroach control in SoHo — and Park Slope across the river is the brownstone-cut-into-flats version at cockroach control in Park Slope. Within your own building, the same riser and party wall carry bed bugs: bed bug treatment in Greenwich Village.

If one line in your building is active and the rest reports nothing, the quiet apartments are where the survey should start. Get in touch and describe the building rather than the count.

Related

• Cockroach Control — how we approach it
• All pest control in Greenwich Village
• Rodent Control in Greenwich Village
• Bed Bug Treatment in Greenwich Village