Containment Netting

Online comments: 1

• Yosep Blake Bak - NYS PE 107881

  COMMENT ON PROPOSED RULE – CONTAINMENT NETTING (PROPOSED 1 RCNY §3307-02)
  Reference: DOB-215 / 2026 RG 031
Submitted by: Yosep Blake Bak, P.E., New York State Professional Engineer, License No. 107881
Capacity: Individual

  I am commenting in an individual capacity. I was one of the engineers who performed the containment netting calculations, oversight, and field verification for the City’s netting pilot at 88-11 Sutphin Boulevard, Queens. My statements about that project are my own field observations. I do not speak for any agency, owner, or contractor, and I am not alleging misconduct by any individual. Each statement of fact is tied to the rule text, a cited document, or my direct observation. Opinions are labeled OPINION.

  1. POSITION AND THE QUESTION
  This comment neither supports nor opposes the rule. Unlike my other comments, it is mainly a question, and I am asking it sincerely:
  What problem is containment netting intended to solve, and what comparison shows that netting solves it better than a shed?
  OPINION: I am not opposed to pilots. I am opposed to predetermined decisions wearing a thin veil of science. I would welcome being shown that this rule is not one.

  2. WHAT THE RULE ITSELF REQUIRES
  Under proposed §3307-02(b), netting is permitted only before façade repair begins. Under (c), the area below must be closed, or protected by a sidewalk shed or equivalent, whenever netting is installed, removed, maintained, or adjusted. Under (d), Code-required pedestrian protection must be in place before façade work starts and before the netting is removed.
  Read together, a netted exposure goes through this sequence:
(i) pedestrian protection and access equipment go up so the netting can be installed;
(ii) the netting stays in place for some period;
(iii) pedestrian protection goes up again for the repair;
(iv) the netting is removed under that protection, and the repair is performed.
  Pedestrian protection is therefore mobilized at least twice for the same exposure, and the netting adds its own installation and removal. At 88-11 Sutphin, installing the netting required scaffold access over an area larger than the repair area, because the netting must be anchored beyond the defective zone. After multiple pull tests failed at the top anchorage, we anchored through the slag-surfaced roof.
  OPINION: Netting would make sense if it could be installed without a shed or scaffold. The rule text says it cannot.
  My specific question is this: what cost and duration comparison did the Department rely on for shed-only versus shed + netting + demobilization + remobilization? A complete comparison would include:
  * overhead protection or closure during installation;
  * access equipment;
  * anchor design, pull testing, and special inspection under BC §1705.37;
  * netting certification;
  * daily and periodic inspections;
  * debris clearing;
  * netting removal;
  * remobilizing protection for the repair;
  * restoring every anchor hole.
  The Mayor’s Office of Operations certified under Charter §1043(d) that this rule minimizes compliance costs. The posted rulemaking record contains that certification but no supporting analysis. I am also not aware of any published evaluation of the 88-11 pilot.

  3. FIELD OBSERVATIONS FROM THE 88-11 PILOT
  (a) Anchor spacing. My calculations for that site governed anchor spacing at 2′-0″ on center. In practice, this meant drilling at 2′-0″ o.c. through both deteriorated and sound masonry around the perimeter of the netted area of a historic courthouse. Each of those holes must be restored when the netting comes down.
  (b) Single-anchor sensitivity. Once debris is caught, the loss of one anchor compromises the section of netting it supports, because the adjacent anchors are designed for the 2′-0″ span, not double it.
  OPINION: I describe this system as fragile. It performs as designed under ideal conditions, but its performance depends on every edge anchor remaining sound in a wall that is, by definition, deteriorating.
  (c) Terminations. The net edges at terminations are exposed.
  (d) Birds. Exposed terminations allow pigeons to get behind the net. At multiple sites with unmaintained bird netting, I have observed birds trapped or nesting behind the net, leaving droppings that slowly deteriorate the masonry.

  4. DRAFTING QUESTIONS IN THE RULE TEXT
  (a) Scope. The Statement of Basis and Purpose describes Local Law 47 as calling for netting rules in two situations: areas with no public access, or an exposure adjoining the one where façade work occurs. Subdivision (b) states neither limit. Please confirm whether (b) is intended to be limited to those two situations, and if so, say so in (b).
  (b) Spacing. Subdivision (e)(1)(i) requires grommets “at least 2 ft on center.” As written, that sets a minimum spacing. If 2 ft is intended as a maximum, it should read “not more than.” Buildings Bulletin 2023-006 required construction documents to show the maximum allowable fastener spacing. Subdivision (g)(7) drops the words “maximum allowable.”
  (c) Anchorage substrate. Subdivision (e)(3)(iii) does not say what the anchors must engage. BB 2023-006 referred designers to BB 2016-005 for post-installed anchors in masonry; the proposed rule does not. Under 1 RCNY §103-04, a cavity wall veneer depends on metal ties to the backup wall for lateral stability, and since Cycle 9 the Department has required probes to confirm those ties exist. Anchoring a net to a veneer loads those same ties. The rule should require that anchors engage the structural backup, not veneer, cladding, or the unsafe element itself, and that terminations be flush. As a practical matter, this limits netting to solid masonry walls.
  (d) Safety factor. Subdivision (e)(2)(i) says loading criteria “should” have a safety factor of 1.3, while (e)(3)(v) says it “must.” The notice defines “shall” and “must” as mandatory but does not define “should.”
  (e) Inspection. Subdivisions (k)(4)–(6) assign inspections to a “qualified person” designated by the permit holder, a term the rule does not define. No inspection scope is specified, and reports are kept on site rather than filed with the Department.
  (f) Duration. The rule sets no maximum time that netting may remain before repair begins. The July 24, 2023 “Get Sheds Down” announcement described buildings using netting as exempt from the proposed monthly shed penalties. The rule does not say whether the Local Law 48 and 51 milestones apply to netting.
  OPINION: “Get Sheds Down” treats the shed as the disease. The shed is the treatment; the disease is the unsafe façade. Measuring success by fewer sheds is like measuring cancer care by how quickly chemotherapy stops. Without a duration limit, netting puts the condition out of sight and out of mind. It also shifts the practical burden of maintenance away from the owner, who must repair, and onto the professionals who must keep inspecting.

  5. REQUESTS
  If the Department adopts this rule, I ask, at minimum, that it:
  1. Duration. Set a maximum period that netting may remain before repair commences, with penalties for delay equivalent to those that apply to sheds under Local Laws 48 and 51.
  2. Robustness. Require that the loss of any single anchor not release the net edge, for example by using an inverted termination bar that captures the net so it holds after a local anchor failure. This is the principle behind the alternate-load-path compliance option in BC §3307.6.4.2.3 for sheds, under which the loss of one vertical member must not cause localized or global failure.
  3. Inspection. Mandate a periodic inspection schedule with a defined scope, filed with the Department. The scope should include photographs of every net end and termination, confirming proper termination and no bird intrusion. Define “qualified person.”
  4. Record. Publish the comparison and the §1043(d) analysis described in Section 2, along with any evaluation of the 88-11 pilot, and clarify items 4(a) through 4(d).
  I would rather understand the Department’s reasoning and be persuaded by it than assume there is none. If there is a comparison, I would like to read it.

  Respectfully submitted,

  Yosep Blake Bak, P.E.
New York State Professional Engineer, License No. 107881

  REFERENCES
  1. DOB, Proposed Rule – Containment Netting, proposed 1 RCNY §3307-02, DOB-215 / 2026 RG 031.
  https://rules.cityofnewyork.us/wp-content/uploads/2026/09/Proposed-Rule-Rule-relating-to-Containment-Netting-1.pdf

  2. DOB Buildings Bulletin 2023-006 (July 25, 2023).
  https://www.nyc.gov/assets/buildings/bldgs_bulletins/bb_2023-006.pdf

  3. 1 RCNY §103-04.
  https://www.nyc.gov/assets/buildings/rules/1_RCNY_103-04.pdf

  4. NYC Mayor’s Office, “Get Sheds Down” announcement, July 24, 2023.
  https://www.nyc.gov/mayors-office/news/2023/07/mayor-adams-dob-commissioner-oddo-plan-remove-unsightly-sheds-scaffolding-nyc

  5. NYC Building Code §3307.6.4.2.3.
  https://codelibrary.amlegal.com/codes/newyorkcity/latest/NYCadmin/0-0-0-186183

  Comment attachment
  Ref.pdf

  Comment added October 5, 2026 12:18pm