Non-potable water systems distribute water that is not designed for human consumption but are an efficient and environmentally friendly way to operate a wide range of appliances, including toilets and irrigation systems. However, it is imperative that this type of system is installed and inspected properly to avoid leaking, or worse, contamination of drinking water. As such, there are eight tests and visual inspections, specified in Sections 108, 312, and Sections 1302.12.1 through 1302.12.7 of the 2022 NYC Plumbing Code, that must be performed to ensure proper installation.

Collection pipe and vent:

Collection pipes and vents can be tested using water, air, or smoke, but must have no leaks and be tight at all points.

Storage tank:

Storage tanks must also be tested for leaks, but there are 3 specific parts of the storage tank that require close inspection. The overflow system must be verified to have no leaks and proper drainage, the tank drain must be observed for proper operation, and the makeup water system must be observed not only for proper operation but also for automatic shutoff of the system at the refill threshold.

Water supply system:

On top of all the previous leak tests, the entire system (or in some cases just the completed portion) must be pressure tested for leaks above its working pressure. This must be done using potable water.

Backflow prevention assemblies:

Errors or defects in backflow prevention assemblies pose some of the highest risk to public health, in that they can contaminate potable water systems. Because of this, all backflow prevention assemblies must be inspected and tested after installation or repairs and annually thereafter. This includes but is not limited to air gaps, spill-proof vacuum breakers, pressure vacuum breaker assemblies, and hose connection backflow preventers.

Vermin and insect protection:

As many non-potable water systems use air gaps and vents, proper measures must be taken to protect the system (and thus the buildings and people who use it) from insects and other vermin.

Water quality:

Though it is not necessary for every system, some non-potable water systems treat the water before it is used. When they do, the water quality must be tested and monitored to ensure safe use.

Cross connection control:

A lot of work goes into backflow prevention and inspection, but all of this becomes for nothing if the nonpotable water system is connected to a potable water system without the proper air gap. On top of this proper signage must be displayed to reduce the risk of future cross connections, and the pipes that carry non-potable water must be purple in color.

Roofwasher (if applicable):

Roofwashers must be tested by introducing water into the gutters to verify that enough rainwater is diverted in order to clear debris, that the amount of diverted water is field adjustable, and that diverted water is drained properly. On top of this, it must be verified that the roofwasher operates automatically and is accessible for maintenance and service.

Every system is unique and poses a unique set of challenges. No matter the type of non-potable water system, we at EPIC are always prepared to provide the diligent oversight and code-required inspections that these systems require.

EP Inspections & Commissioning hit a major milestone as the firm has officially expanded its Class 1 Accreditation from the International Accreditation Service (IAS) to cover all Special Inspections offered in New York City.

This achievement builds on EPIC’s initial Class 1 accreditation, obtained in May 2021 for a limited number of inspection types. Since then, the team has worked diligently through the rigorous annual renewal process and added 34 additional inspection categories—broadening their capabilities to include inspections for projects of any class and size, from small renovations to large-scale high-rise developments.

With this expansion, EPIC is now authorized to conduct critical inspections such as support of excavation, structural foundations, deep foundations, seismic resistance, and all types of mass timber construction, in addition to their existing specialties like mechanical systems, sprinkler and standpipe systems, and emergency power systems.

As a fully accredited Class 1 firm, EPIC continues to set the standard in the industry—known for their engineer-led approach, clear communication, and commitment to quality. This expanded scope reinforces EPIC’s role as a trusted partner on complex construction projects across New York City.

As large Mass Timber construction has become more of a reality in New York City in recent years, there has been a lot of code development for Mass Timber construction in NYC and International building codes, having both design and inspection implications. (See this DoB presentation regarding the most recent code changes regarding Mass Timber). To appropriately specify the correct inspection types when filing projects on DoB Now, it's important to distinguish between Engineered Wood Products and Conventional Wood Construction.

Engineered wood products, such as Cross Laminated Timber (CLT), Structural Composite Lumber (SCL) or Structural Glued-Laminated Timber (Glulam) are described are defined in the NYC Building code as follows:

• CROSS-LAMINATED TIMBER (CLT): A prefabricated engineered wood product made of at least three orthogonal layers of graded sawn lumber or structural composite lumber (SCL) that are laminated by gluing with structural adhesives.

• STRUCTURAL COMPOSITE LUMBER: Structural member manufactured using wood elements bonded together with exterior adhesives.

• STRUCTURAL GLUED-LAMINATED TIMBER: An engineered, stress-rated product of a timber laminating plant, comprised of assemblies of specially selected and prepared wood laminations in which the grain of all laminations is approximately parallel longitudinally and the laminations are bonded with adhesives.

The products listed above come with sets of rules for attachment, notching, bearing, connector installation, erection, etc., that are usually listed by the manufacturer.

Engineered wood products can fall under the full list of Wood Construction Inspections per NYC Building code, found in section 1705.5, depending on the EoR specifications. These inspection types are:

1. 1705.5.1 High-Load Diaphragms

2. 1705.5.2 Metal-Plate-Connected Wood Trusses

3. 1705.5.3 Prefabricated Wood I-Joists and/or Glued Prefabricated Parallel Chord Wood Trusses

4. 1705.5.4 Other Structural Wood Construction 

5. 1705.5.5 Special Inspection for Seismic Resistance

6. 1705.5.6 Type IV Construction

Conventional light framed wood construction inspections fall under the progress inspection 1705.5.4 Other Structural Wood Construction:

All other structural wood construction shall be subject to progress inspections for the structural frame to the extent required by Section 110.3.3.

110.3.3 Structural Wood Frame Inspection (in the Administrative chapter of the Building Code) states:

Inspections shall be performed for wood structural framing to determine compliance with the approved construction documents.

The reality is that with New York City's overwhelming existing building stock of townhouses, rowhouses, tenements and 1-2 family detached houses, the bulk of construction and inspection work in terms of wood construction comes down the conventional wood construction. Types of buildings listed above rely on wood framed floors, diaphragms, and sometimes wood framed bearing walls. Any time the framing is altered, the load path needs to be re-established, framing and sheathing designed and inspected as per code.

EPIC provides a comprehensive inspection program for wood construction, whether it be type IV construction, light framed wood construction, high load diaphragms, or any other wood construction type. With our qualified staff and detailed inspection checklists we deliver high quality oversight of the wood construction to ensure adherence with construction documents and all code requirements.

As of December 11, 2024, the definition of “Major Building” is changing in New York City. The definition of "Major Building” is found in the NYC Building Code Chapter 2, Section 202. Currently the definition reads that a Major Building is:

An existing or proposed building 10 or more stories or 125 feet (38,100 mm) or more in height, or an existing or proposed building with a building footprint of 100,000 square feet (30,480 m^2) or more regardless of height, or an existing or proposed building so designated by the commissioner due to unique hazards associated with the construction or demolition of the structure.

The new definition, affecting all projects filed on December 11th and therafter, will be:

An existing or proposed building seven or more stories or 75 feet (22,860 mm) or more in height, or an existing or proposed building with a building footprint of 100,000 square feet (30,480 m^2 ) or more regardless of height, or an existing or proposed building so designated by the commissioner due to unique hazards associated with the construction or demolition of the structure.

The change lowers the height of a Major Building by 50 feet, down to 75 feet, or by 3 stories, down to 7 stories total. The definition of Major Building affects what projects qualify as Class 1 for the purposes of special inspections. As previously discussed in an EPIC Knows article, a Class 1 Special Inspection Agency can inspect:

• The construction of a new major building;

• The full demolition of a major building;

• The alteration of a major building including:

• The removal of an entire story or more;

• The partial demolition of twenty thousand (20,000) square feet or more of gross floor area; or

• The partial demolition of twenty (20) percent or more of the gross floor area.

• The enlargement of a major building by more than ten thousand (10,000) square feet of gross floor area.

Due to this change to the definition of Major Buildings, more projects in New York City will fall into the Class 1 category, requiring an International Accreditation Service, Inc. (IAS) or an equivalent accreditation agency accredited Special Inspection Agency to perform their special and progress inspections. EP Inspections + Commissioning is a Class 1 accredited Special Inspection Agency in a vast variety of TR1 inspection types, and is qualified to perform inspections on Class 1, Class 2, and Class 3 projects.