347-392-6356Contact Us
N
Nacmias Law Firm, PLLC

NYC Building Code

§ 405.4.2 — § 405.4.2

Talk to an AttorneyView on AmLegalCall 347-392-6356

Brooklyn since 2014All five boroughsSame-day response during business hours

What is NYC BC § 405.4.2?

Quick Answer

This section establishes requirements for compartment separation in buildings, mandating a minimum 2-hour fire barrier wall construction from floor slab to floor deck. It specifies limitations on penetrations, fire door assembly protections, and independent air supply and exhaust systems for each compartment. Applies to building owners responsible for compliance with fire safety regulations.

General informational summary. Not legal advice for your situation. Consult an attorney before acting on any specific matter.

Michael Nacmias - Founding PartnerMichael Sargo - Partner
From the team atNacmias Law Firm, PLLCBrooklyn-based attorneys representingproperty owners across all five boroughsMeet the team →

405.4.2 Compartment separation.

BC § 405.4.2

The separation between the two compartments shall be of minimum 2-hour fire barrier wall construction that shall extend from floor slab to floor deck above. Penetrations between the two compartments shall be limited to plumbing and electrical piping and conduit that are firestopped in accordance with Section 714. Doorways shall be protected by fire door assemblies that are automatic-closing by smoke detection in accordance with Section 716.5.9.3 and are installed in accordance with NFPA 105 and Section 716.5.3 of this code. Where provided, each compartment shall have an air supply and an exhaust system independent of the other compartments.

Common Questions

Our team

Meet the people you will work with

View all team members

Resources & updates

Practical resources for NYC legal problems.

Browse practical legal articles, violation-code tools, city-agency resources, and searchable references without leaving the landing page.

DOB Violations

NYC DOB Certificate of Correction: New DOB NOW Safety Portal Launches December 2025

The new DOB NOW: Safety portal is live as of December 15, 2025. Learn the 5 key changes, step-by-step submission process, and how to avoid the 20 common disapproval reasons.

8 min readOpen
Building Code Violations

What Are the Critical NYC DOB Updates for December 2025?

NYC property owners face urgent DOB deadlines: a historic basement legalization program, year-end inspection reports due December 31st, and the new 2025 Electrical Code effective December 21st. Here's what you need to know.

8 min readOpen
DOB Violations

Understanding DOB Violations: A Complete Guide

Your complete guide to understanding, navigating, and resolving NYC Department of Buildings violations with confidence. Learn about violation classes, penalties, and resolution strategies.

15 min readOpen
Traffic Violations

NYC Failure-to-Yield (§ 19-190[b]) at OATH: What to Expect

Complete guide to NYC Admin Code § 19-190(b) 'Failure to Yield Causing Physical Injury' summonses at OATH. Learn about phone hearings, flat fee structure, and what to expect from the process.

8 min readOpen
1 / 2

Need something specific? Search the full resources library for articles, agencies, violation codes, and legal-code references.

Search all resources

Free case review

Have a matter that touches § 405.4.2?

Free 15-minute case review with the attorney handling your matter. Same-day response during business hours across all five boroughs — OATH hearings, Housing Court, and real estate closings.

Schedule ConsultationCall 347-392-6356

Or email us

[email protected]

An attorney reads every message.

  • Same-day response

    During business hours

  • Direct attorney access

    Same lawyer from intake to close

  • Flat-fee pricing

    On most OATH and closing matters