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NFPA 70, NATIONAL ELECTRICAL CODE, NEC 2011
SIMTRA® SMART CABLE APPLICABLE NEC ARTICLES
Code Standards herein are listed for reference only, including revisions by issuing authority, form
a part of this specification section to the extent indicated. Standards listed are identified by
issuing authority, authority abbreviation or acronym, designation number, title or other designation
established by issuing authority. Standards subsequently referenced herein are referred to by
issuing authority abbreviation and standard designation.
Chapter 3 Wiring Methods and Materials
Article 300 Wiring Methods
300.1 Scope.
(A) All Wiring Installations. This article covers wiring methods for all wiring installations unless
modified by other articles.
300.2 Limitations.
(A) Voltage. Wiring methods specified in Chapter 3 shall be used for 600 volts, nominal, or less
where not specifically limited in some section of Chapter 3. They shall be permitted for over 600
volts, nominal, where specifically permitted elsewhere in this Code.
300.3(C) Conductors of Different Systems.
(1) 600 Volts, Nominal, or Less. Conductors of ac and dc circuits, rated 600 volts, nominal, or
less, shall be permitted to occupy the same equipment wiring enclosure, cable, or raceway. All
conductors shall have an insulation rating equal to at least the maximum circuit voltage applied to
any conductor within the enclosure, cable, or raceway.
Informational Note No. 1: See 725.136(A) for Class 2 and Class 3 circuit conductors.
Clarification note: National Electrical Code Handbook 2011. Section 300.3(C)(1) makes it clear
that the maximum circuit voltage in the raceway, not the maximum insulation voltage rating of the
conductors in the raceway, is what determines the minimum voltage rating required for the
insulation of the conductors for systems of 600 volts or less.
Article 330 Metal-Clad Cable: Type MC
330.1 Scope.
This article covers the use, installation, and construction specifications of metal-clad cable, Type
MC
II. Installation
330.10 Uses Permitted.
(A)(2) For power, lighting, control and signal circuits.
(B) Specific Uses. Type MC cable shall be permitted to be installed in compliance with Parts II
and III of Article 725 and 770.133 as applicable and in accordance with 330.10(B)(1) through
(B)(4).
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Article 334 Nonmetallic-Sheathed Cable: Types NM, NMC, and NMS
334.1 Scope.
This article covers the use, installation, and construction specifications of nonmetallic-sheath
cable.
334.2 Definitions.
Nonmetallic-Sheathed Cable. A factory assembly of two or more insulated conductors enclosed
within an overall nonmetallic jacket.
Type NM. Insulated conductors enclosed within an overall nonmetallic jacket.
Type NMS. Insulated power or control conductors with signaling, data, and communications
conductors within an overall nonmetallic jacket.
334.6 Listed.
Type NM, Type NMC, and Type NMS cables shall be listed.
II. Installation
334.10 Uses Permitted.
Type NM, Type NMC, and Type NMS cables shall be permitted to be used in the following:
(5) Types I and II construction where installed within raceways permitted to be installed in Types I
and II construction.
III. Construction Specifications
334.100 Construction.
The outer cable sheath of nonmetallic-sheathed cable shall be a nonmetallic material.
334.104 Conductors.
The 600-volt insulated conductors shall be sizes 14 AWG through 2 AWG copper conductors or
sizes 12 AWG through 2 AWG aluminum or copper-clad aluminum conductors. The
communications conductors shall comply with Part V of Article 800.
334.112 Insulation.
The insulated power conductors shall be one of the types listed in Table 310.104(A) that are
suitable for branch-circuit wiring or one that is identified for use in these cables. Conductor
insulation shall be rated at 90C (194F).
Informational Note: Types NM, NMC, and NMS cable identified by markings NM-B, NMC-B, and
NMS-B meet this requirement.
334.116 Sheath.
The outer sheath of the nonmetallic-sheath cable shall comply with 334.116(A), (B), and (C).
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(A) Type NM. The overall covering shall be flame retardant and moisture resistant.
(B) Type NMC. The overall covering shall be flame retardant, moisture resistant, fungus resistant,
and corrosion resistant.
(C) Type NMS. The overall covering shall be flame resistant and moisture resistant. The sheath
shall be applied so as to separate the power conductors from the communications conductors.
Article 336 Power and Control Cable: Type TC
336.1 Scope.
This article covers the use, installation, and construction specifications for power and control tray
cable. Type TC.
II. Installation
336.10 Uses Permitted.
Type TC cable shall be permitted to be used as follows:
(5) For Class 1 Circuits as permitted in Parts II and III of Article 725.
Chapter 7 Special Conditions
Article 725 Class 1, Class2, and Class 3 Remote-Control, Signaling, and Power-Limited
Circuits
725.1 Scope.
This article covers remote-control, signaling, and power-limited circuits that are not an integral
part of a device or appliance.
725.136 Separation from Electric Light, Power, Class 1, Non-Power-Limited Fire Alarm
Circuit Conductors, and Medium-Power Network-Powered Broadband Communications
Cables.
(B) Separated by Barriers. Class 2 and Class 3 circuits shall be permitted to be installed together
with the conductors of electric light, power, Class 1, non-power-limited fire alarm and medium
power network-powered broadband communications circuits where they are separated by a
barrier.
(I) Other Applications.
(1) Either (a) all of the electric light, power, class 1, non-power-limited fire alarm and mediumpower network powered broadband communications circuit conductors or (b) all of the Class 2
and Class 3 circuit conductors are in a raceway or in metal-sheathed, metal-clad, non-metallicsheathed, or Type UF cables.
(2) All of the electric light, power, Class 1 non-power-limited fire alarm, and medium-power
network-powered broadband communications circuit conductors are permanently separated from
all of the Class 2 and Class 3 circuit conductors by a continuous and firmly fixed nonconductor,
such as porcelain tubes or flexible tubing, in addition to the insulation on the conductors.
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Article 760 Fire Alarm Systems
760.1 Scope.
This article covers the installation of wiring and equipment of fire alarm systems including all
circuits controlled and powered by the fire alarm system.
760.136 Separation from Electric Light, Power, Class 1, NPLFA, and Medium-Power
Network-Powered Broadband Communications Circuit Conductors.
(B) Separation by Barriers. Power-limited fire alarm circuit cables shall be permitted to be
installed together with Class 1, non-power-limited fire alarm, and medium-power networkpowered broadband communications circuits where they are separated by a barrier.
(G) Other Applications.
(1) Either (a) all of the electric light, power, class 1, non-power-limited fire alarm and mediumpower network powered broadband communications circuit conductors or (b) all of the powerlimited fire alarm circuit conductors are in a raceway or in metal-sheathed, metal-clad, nonmetallic-sheathed, or Type UF cables.
(2) All of the electric light, power, Class 1 non-power-limited fire alarm, and medium-power
network-powered broadband communications circuit conductors are permanently separated from
all of the power-limited fire alarm circuit conductors by a continuous and firmly fixed
nonconductor, such as porcelain tubes or flexible tubing, in addition to the insulation on the
conductors.
Article 770 Optical Fiber Cables and Raceways
770.1 Scope.
The provisions of this article apply to the installation of optical fiber cables, raceways, and cable
routing assemblies. This article does not cover the construction of optical fiber cables and
raceways.
770.2 Definitions.
Composite Optical Fiber Cable. A cable containing optical fibers and current-carrying electrical
conductors.
770.3 Other Articles.
(B) Composite Cables. Composite optical fiber cables shall be classified as electrical cables in
accordance with the type of electrical conductors. They shall be constructed, listed, and marked
in accordance with the appropriate article for each type of electrical cable.
770.133 Installation of Optical Fibers and Electrical Conductors.
(A) With Conductors for Electric Light, Power, Class 1, non-Power-Limited Fire Alarm, or Medium
Power Network-Powered Broadband Communications Circuits. When optical fibers are within the
same composite cable for electric light, power, Class 1, non-power-limited fire alarm, or mediumpower network-powered broadband communications circuits operating at 600 volts or less, they
shall be permitted to be installed only where the functions of the optical fibers and electrical
conductors are associated. Nonconductive optical fiber cables shall be permitted to occupy the
same cable tray or raceway with conductors for electric light, power, Class 1, non-power-limited
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fire alarm, Type ITC, or medium-power network-powered broadband communications circuits,
operating at 600 volts or less.
Exception No. 5: Where all of the conductors of electric light, power, class 1, non-power-limited
fire alarm, and medium-power network-powered broadband communications circuits are
separated from all of the optical fiber cables by a permanent barrier or listed divider.
Chapter 8 Communication Systems
Article 800 Communications Circuits
800.1 Scope.
This article covers communications circuits and equipment.
800.2 Definitions.
Communication Circuit. The circuit that extends voice, audio, video, data, interactive services,
telegraph (except radio), outside wiring for fire alarm and burglar alarm from the communications
utility to the customer's communications equipment up to and including terminal equipment such
as a telephone, fax machine, or answering machine.
V. Installation Methods Within Buildings
800.110 Raceways for Communications Wires and Cables.
(A) Types of Raceways. Communications wire and cables shall be permitted to be installed in any
raceway that complies with either (A)(1) or (A)(2).
(1) Raceways Recognized in Chapter 3. Communications wires and cables shall be permitted to
be installed in any raceway included in chapter 3. The raceway shall be installed in accordance
with the requirements of Chapter 3.
(2) Other Permitted Raceways. Communication wires and cables shall be permitted to be
installed in listed plenum communications raceway, listed riser communications raceway, or listed
general-purpose communications raceway selected in accordance with provisions of 800.113,
and installed in accordance with 362.24 trough 362.56, where requirements applicable to
electrical nonmetallic tubing apply.
800.133 Installation of Communications Wires, Cables, and Equipment.
(A) Separation from Other Conductors
(1) In Raceway, Cable Trays, Boxes, Cables, and Enclosures
(d) Electric Light, Power, Class 1, Non-Power-Limited Fire Alarm, and Medium-Power NetworkPowered Broadband Communications Circuits in Raceways, Compartments, and Boxes.
Communications conductors shall not be placed in any raceway, compartment, outlet box,
junction box, or similar fitting with conductors of electric light, power, Class 1, non-power-limited
fire alarm, or medium-power network-powered broadband communication circuits.
Exception No. 1: Where all the conductors of electric light, power, Class 1, non-power-limited fire
alarm, and medium-power network-powered broadband communications circuits are separated
from all of the conductors of communications circuits by a permanent barrier or listed divider.
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(2) Other Applications. Communications wire and cables shall be separated at least 50 mm (2 in.)
from the conductors of electric light, power, Class 1, non-power-limited fire alarm, or mediumpower network-powered broadband communications circuits.
Exception No. 1: Where either (1) all the conductors of the electric light, power, Class 1, nonpower-limited fire alarm, and medium-power network-powered broadband communications
circuits are in a raceway or in metal sheathed, metal-clad, nonmetallic-sheathed, Type AC, or
Type UF cables, or (2) all of the conductors of communications circuits are enclosed in raceway.
Exception No. 2: Where the communications wires and cables are permanently separated from
the conductors of electric light, power, Class 1, non-power-limited fire alarm, and medium-power
network-powered broadband communications circuits by a continuous and firmly fixed
nonconductor, such as porcelain tubes or flexible tubing, in addition to the insulation on the wire.
VI. Listing Requirements
800.179 Communication Wires and Cables.
Communications wire and cables shall be listed in accordance with 800.179(A) through (I) and
marked in accordance with Table 800.179. Conductors in communications cables, other than in a
coaxial cable, shall be copper. Communications wire and cables shall have a voltage rating of not
less than 300 volts. The insulation for the individual conductors, other than the outer conductor of
a coaxial cable, shall be rated for 300 volts minimum. The cable voltage rating shall not be
marked on the cable or on the under carpet communications wire. Communications wires and
cables shall have a temperature rating of not less than 60C.
(A) Type CMP.
(B) Type CMR.
(C) Type CMG.
(D) Type CM.
(E) Type CMX.
(G) Communications Circuit Integrity (CI) Cables. Cables suitable for use in communications
systems to ensure survivability of critical circuits during a specified time under fire conditions shall
be listed as circuit integrity (CI) cable. Cables identified in 800.179(A) through (E) that meet the
requirements for circuit integrity shall have the additional classification using the suffix "CI".
(H) Communications Wires. Communications wires, such as distributing frame and jumper wire,
shall be listed as being resistant to the spread of fire.
(I) Hybrid Power and Communications Cables. Listed hybrid power and communications cables
shall be permitted where the power cable is a listed Type NM or NM-B conforming to the
provisions of Article 334, and the communications cable is listed Type CM, the jackets on the
listed NM or NM-B and listed CM cables are rated for 600 volts minimum, and the hybrid cable is
listed as being resistant to the spread of fire.
Article 820 Community Antenna Television and Radio Distribution Systems
820.1 Scope.
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This article covers coaxial distribution of radio frequency signals typically employed in community
antenna television (CATV) systems.
V. Installation Methods Within Buildings.
820.110 Raceways for Coaxial Cables.
(A) Types of Raceways. Coaxial cables shall be permitted to be installed in any raceway that
complies with either (A)(1) or (A)(2).
(1) Raceways Recognized in Chapter 3. Coaxial cables shall be permitted to be installed in any
raceway included in chapter 3. The raceway shall be installed in accordance with the
requirements of Chapter 3.
(2) Other Permitted Raceways. Coaxial cables shall be permitted to be installed in listed plenum
communications raceway, listed riser communications raceway, or listed general-purpose
communications raceway selected in accordance with provisions of 820.113, and installed in
accordance with 362.24 trough 362.56, where requirements applicable to electrical nonmetallic
tubing apply.
820.133 Installation of Coaxial Cables and Equipment.
(A) Separation from Other Conductors.
(1) In Raceways, Routing Assemblies, Cable Trays, Boxes, and Enclosures.
(C) Electric Light, Power, Class 1, Non-Power-Limited Fire Alarm, and Medium-Power NetworkPowered Broadband Communications Circuits. Coaxial cable shall not be placed in any raceway,
compartment, outlet box, junction box, or other enclosures with conductors of electric light, power,
Class 1, non-power-limited fire alarm, or medium-power network-powered broadband
communication circuits.
Exception No. 1: Where all the conductors of electric light, power, Class 1, non-power-limited fire
alarm, and medium-power network-powered broadband communications circuits are separated
from all of the coaxial cables by a permanent barrier or listed divider.
(2) Other Applications. Coaxial cables shall be separated at least 50 mm (2 in.) from the
conductors of electric light, power, Class 1, non-power-limited fire alarm, or medium-power
network-powered broadband communications circuits.
Exception No. 1: Where either (1) all the conductors of the electric light, power, Class 1, nonpower-limited fire alarm, and medium-power network-powered broadband communications
circuits are in a raceway or in metal sheathed, metal-clad, nonmetallic-sheathed, Type AC, or
Type UF cables, or (2) all of the conductors of coaxial cables are enclosed in raceway.
Exception No. 2: Where the coaxial cables are permanently separated from the conductors of
electric light, power, Class 1, non-power-limited fire alarm, and medium-power network-powered
broadband communications circuits by a continuous and firmly fixed nonconductor, such as
porcelain tubes or flexible tubing, in addition to the insulation on the wire.
Article 830 Network-Powered Broadband Communications Systems
830.1 Scope.
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This article covers network-powered broadband communications systems that provide any
combination of voice, audio, video, data, and interactive services through a network interface unit.
V. Installation Methods Within Buildings.
830.110 Raceways for Low-Powered and Medium-Powered Network-Powered Broadband
Communications Cables.
(A) Raceways Recognized in Chapter 3. Low - and medium-power network-powered broadband
communications cables shall be permitted to be installed in any raceway included in Chapter 3.
The raceway shall be installed in accordance with the requirements of Chapter 3.
(B) Raceway Fill for Network-Powered Broadband Communications Cables. Raceway fill for
network-powered broadband communications cables shall comply with either (B)(1) or (B)(2).
(1) Low-Power Network-Powered Broadband Communications Cables. The raceway fill
requirements for Chapter 3 and 9 shall not apply to low-powered broadband communications
cables.
(2) Medium-Power Network-Powered Broadband Communications Cables. Where medium-power
network-powered broadband communications cables are installed in a raceway, the raceway fill
requirements of Chapter 3 and 9 shall apply.
830.133 Installation of Network-Powered Broadband Communications Cables and
Equipment.
Cable and equipment installations within buildings shall comply with 830.133(A) through (C), as
applicable.
(A) Separation from Other Conductors
(1) In Raceway, Cable Trays, Boxes, and Enclosures
(f) Electric Light, Power, Class 1, Non-Powered Broadband Communications Circuit Cables.
Network-powered broadband communications cable shall not be placed in any raceway, cable
tray, compartment, outlet box, junction box, or similar fittings with conductors of electric light,
power, Class 1, or non-power-limited fire alarm circuit cables.
Exception No. 1: Where all the conductors of electric light, power, Class 1, non-power-limited fire
alarm circuits are separated from all of the network-powered broadband communications cables
by a permanent barrier or listed divider.
(2) Other Applications. Network-powered broadband communications cables shall be separated
at least 50 mm (2 in.) from the conductors of electric light, power, Class 1, non-power-limited fire
alarm circuits.
Exception No. 1: Where either (1) all the conductors of the electric light, power, Class 1, nonpower-limited fire alarm circuits are in a raceway or in metal sheathed, metal-clad, nonmetallicsheathed, Type AC, or Type UF cables, or (2) all of the network-powered broadband
communications cables are enclosed in raceway.
Exception No. 2: Where the network-powered broadband communications cables are
permanently separated from the conductors of electric light, power, Class 1, non-power-limited
fire alarm circuits by a continuous and firmly fixed nonconductor, such as porcelain tubes or
flexible tubing, in addition to the insulation on the wire.
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NEC Article 725 Class 1, Class 2, and Class 3 Remote-Control, Signaling, and PowerLimited Circuits
This article covers the installation of remote control, signaling, and power-limited circuits that are
not an integral part of a device or appliance. Also provides safeguards to limit the amount of
energy that can be introduced into low-voltage components and circuits and provides
requirements related to the products of combustion and flame-spread ratings for signaling
systems and remote-control wiring. To know when to use the requirements for control, signaling,
and power-limited circuits we should know the following descriptions:
Remote-Control Circuit
Any electrical circuit that controls any other circuit through a relay or an equivalent device.
Signaling Circuit
Any electrical circuit that energizes signaling equipment.
Circuit Classification
Circuit classification is based primarily on the circuit power supply. The classes of circuits are
divided into Class 1, Class 2, and Class 3 and are classified as remote control, signaling, and
power-limited circuits by the NEC. These circuits are differentiated by their function and power
limitation, which isolates them from lighting and power circuits. Also these circuits are categorized
according with their specific voltage and power limitations.
Class 1 Circuit
The portion of the wiring system between the load side of the over current device (fuse or circuit
breaker) or power-limited supply and the connected equipment. Class 1 circuits shall comply with
Part I and II of the NEC article 725.
Class 1 circuits are classified either as power-limited circuits and shall comply with the power
limitations of the NEC Section 725.41.(a) or they are classified as remote control and signaling
circuits and shall comply with the power limitations of the NEC Section 725.41.(b).
Insulation on conductors for Class 1 circuits is required to be suitable for 600 volts. Conductors
larger than No. 16 shall comply with the requirements of NEC Article 310.
Class 1 Power-Limited Circuits
These circuits are used for functions other than signaling or remote control. These circuits shall
be permitted to be either AC or DC and shall be supplied from a source that has a rated output of
not more than 30 volts and 1000 volt-amperes. These circuits are provided with a current limiter
on the power source that supplies them. This limiter is an over current device (fuse or circuit
breaker) or power-limited supply (transformer) that restricts the amount of supplies current on the
circuit in the event of an overload, short circuit, or ground-fault.
Typical use of Class 1 Power-Limited circuits: Low-voltage under counter lighting system, 24 volt
circuit used to operate low-voltage damper motors to control environmental airflow.
Class 1 Remote-Control Circuits
These circuits are used to control another circuit through a relay or equivalent device. These
circuits shall not exceed 600 volts. The power output of the source is not required to be power
limited. These circuits shall satisfy the majority of the same wiring requirements for power and
light circuits.
Typical use of Class 1 Remote-Control Circuits: Elevators, conveyors, 120 volt circuit that
operates the coil of a motor starter or lighting contractor, the 24 volt circuit for a garage door,
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motor controllers which operate mechanical process, shunt-trip circuits for circuit breakers,
equipment controlled from one or more location.
Class 1 Signaling Circuits
These circuits are used to energize signaling equipment. These circuits shall not exceed 600
volts. The power output of the source is not required to be power limited. These circuits shall
satisfy the majority of the same wiring requirements for power and light circuits.
Typical use of Signaling Circuits: Doorbells, buzzers, signal lights, annunciators, burglar alarm,
electric clock system, factory call system, listed nurse call system with a power supply with an
output of 500 watts at 24 volts, and other detection indication or alarm devices.
Class 2 Circuit
The portion of the wiring system between the load side of a Class 2 power source and the
connected equipment. Due to its power limitations, a Class 2 circuit considers safety from a fire
initiation standpoint and provides acceptable protection from electric shock. In general, a Class 2
circuit work at 30 volts or less with a power supply not exceeding 100 VA, and the current to 5mA
for circuits over 30 volts. See NEC Chapter 9, Table 11(A) where provides the power limitations
for the power source. Class 2 circuits shall comply with NEC Article 725 Parts I and III, which are
referenced by FPN No.2 to 725.52.
Typical use of Class 2 Circuits: Circuits used to interconnect computers for the intention of
transfer data, thermostats for heating system, small bell or buzzer system, annunciators systems,
small intercom phone systems in which a battery and the ringing circuit supply the voice circuit. A
dry cell battery shall be considered an inherently limited Class 2 power source, provided the
voltage is 30 volts or less and the capacity is equal to or less than that available from series
connected No, 6 carbon zinc cells.
Class 3 Circuit
The portion of the wiring system between the load side of a Class 3 power source and the
connected equipment. Due to its power limitations, a Class 3 circuit considers safety from a fire
initiation standpoint. Since higher levels of voltage and current than for Class 2 are permitted,
additional safeguards are specified to provide protection from an electric shock hazard that could
be encountered. In general, a Class 3 circuits are used when the power demand exceeds 0.50
VA and the power supply not exceeding 100 VA, for circuits over 30 volts. See NEC Chapter 9,
Table 11(B) where provides the power limitations for the power source. Class 3 circuits shall
comply with NEC Article 725 Parts I and III, which are referenced by FPN No.2 to 725.52.
Typical use of Class 3 Circuits: Circuits used to interconnect computers for the intention of
transfer data, Class 3 circuitry and accessories can be designed to alleviate the problem of
excessive voltage drop, hospital nurse call system with a power supply rated at 100 VA and 100
volts.
Building Construction Types
All buildings are classified according to their construction type. Type I is least combustible and
Type V is most combustible. The more combustible a building is and the more hazardous the use
is, the more the maximum allowable area is limited. All construction types and use groups are
allowed to have increased areas by using sprinklers.
Building Construction Type I
Type I construction is fire-resistive with non-combustible construction materials. This type of
construction is for “all occupancy type” and can be of unlimited height (Commonly found in highrise buildings, Group 1 occupancies, mid-rise office and Group R Buildings). Typically these are
concrete frame buildings made of noncombustible materials. All of the building elements
(structural frame, bearing walls, floors and roofs) are fire resistance rated.
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Building Construction Type II
Type II construction has 3 categories with non-combustible construction materials, fire-resistive,
one-hour rated, and non-rated. The number of “stories” permitted varies from 2 to 12, depending
in the category rated (Commonly found in newer school buildings, commercial buildings, etc.).
These buildings are constructed of noncombustible materials. Typically these are masonry
bearing walls structures with steel studs for walls and steel bar joists for floor and roof structures.
IIA has fire rated building elements (structural frame, bearing walls, floors and roofs). IIB is the
most common construction type for commercial buildings because the building elements are not
required to be fire resistance rated but still must be non-combustible.
Building Construction Type III
Type III construction has 2 categories with protected combustible or unprotected combustible
construction materials, non-rated, non-rated with sprinkler, one-hour rated, and one-hour rated
with sprinkler. The number of “stories” permitted varies from 4 to 5, depending in the category
rated commonly found in “warehouse districts of older cities, multifamily dwellings buildings, etc.
Type III construction is the type of construction in which the exterior walls are of noncombustible
materials and the interior building elements are of any material permitted by the code
(combustible or non-combustible). This is typical of buildings with masonry bearing walls and
wood roofs or floors.
Building Construction Type IV
Type IV has 1 category with heavy timber and heavy timber with sprinkler. The number of
“stories” permitted varies from 4 to 5 depending in the category rated (commonly found in
multifamily dwellings buildings, etc.). This is Heavy Timber construction which is not common
except perhaps in some worship facilities.
Building Construction Type V
Type V construction has 2 categories with protected wood frame or unprotected wood frame
construction materials, non-rated, non-rated with sprinkler, one-hour rated, and one-hour rated
with sprinkler. The number of “stories” permitted varies from 2 to 4, depending in the category
rated (commonly found in newer apartment buildings, etc.). Type V construction is typically wood
frame construction. V-A requires fire rated assemblies for all building elements (structural frame,
bearing walls, floors and roofs); this is often seen in older construction that predates sprinklers
but still not commonly used. V-B is very common because it does not require any fire rating.
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