washington state wac rules

[rickl]

hi i have a couple of questions on the wac rules
QUESTION: 1: wac 296-46b-334, whats is the definition of structure type III,IV,V construction

QUESTION 2: i hope i'm wrong but the way i read the 2004 rules you can now install nmb in commerial offices & buildings that are structure type III,IV,V? as long as the cable is concealed and has a 15 minute fire rating. before it was cut and dry,[NONMETALLIC-SHEATHED CABLE NOT ALLOWED,except in one-and two-family dwellings.]

QUESTION 3: on new commercial building, the property owner or primary lessee can do all the electrical work on the property as long as the new building is not intended for rent, sale, or lease.
so basicily the state has open the flood gates to all the handyman who for years have be doing residential work illegaly to start doing commercial work illegaly. please somebody remind me why i pay $$$$ every year for my master and contracting license. SORRY JUST VENTING

QUESTION 4: what are class b work labels ( wac 296-46b-905{15}) page 47

 

[paul]

Re: washington state wac rules

WAC 296-46B-334 reads as follows:

Wiring methods and materials -- Nonmetallic-sheathed cable.

010 Nonmetallic-sheathed cable.

(1) The building classification, for subsections (2) and (3) of this section, will be as determined by the building official. For the purposes of this section, Type III, IV and V may be as defined in the International Building Code adopted in the state of Washington. The installer must provide the inspector documentation substantiating the type of building construction and finish material rating(s) prior to any electrical inspection.

(2) This section replaces NEC 334.10(2). In multifamily dwellings, Type NM, Type NMC, and Type NMS cable(s) may be used in structures of Types III, IV, and V construction except as prohibited in NEC 334.12.

(3) This section replaces NEC 334.10(3). In all other structures, Type NM, Type NMC, and Type NMS cable(s) may be used in structures of Types III, IV, and V construction except as prohibited in NEC 334.12. All cable(s) must be concealed within walls, floors, or ceilings that provide a thermal barrier of material that has at least a 15-minute finish rating as identified in listings of fire-rated assemblies.

==============================================

There are only minor changes between the WAC and the NEC. I believe it's only for clarification purposes. As far as running NM in commercial spaces, it was allowed before if under a certain sq. footage. I can remember only one job where we did this at the customers request to shave costs however possible because of their cash flow at the time.

As for the ratings, they are fire ratings for combustable buildings. Taken from: http://dl.ccc.cccd.edu/classes/internet/bldg300/ss3.htm

Types of Construction ? Construction Classification

Type I buildings are noncombustible, and the building elements are also provided with a mandated degree of fire resistance. This type of construction requires the highest level of fire protection specified in the code. Type II buildings are also of noncombustible construction; however, the level of fire resistance is usually less than that required for Type I structures. Buildings of Type II construction may have a limited degree of fire resistance (Type IIA), or no fire resistance whatsoever (Type IIB).

Type III buildings are considered combustible buildings and are either protected or unprotected. This building type was developed out of the necessity to prevent conflagrations in heavily built-up areas where buildings were erected side-by-side in congested downtown business districts. To limit the spread of fire from building to building, exterior walls were required to be of both noncombustible and fire-resistant construction.

Referred to as ?heavy-timber,? buildings of Type IV construction are essentially Type III buildings with an interior of timber members. To conform to Type IV construction, building members must be of substantial thickness. Given the characteristics of massive wood members, there is little chance for sudden structural collapse during or after a fire.

Type V buildings are essentially construction systems that will not fit into any of the other types of construction specified by the IBC. While the construction normally considered Type V is the conventional light-frame wood building, any combination of approved materials can be considered Type V construction. Section 602.1 indicates that a building is not required to conform to the details of a type of construction higher than that type that meets the minimum requirements based on occupancy, even though certain features of such a building actually conform to a higher construction type.

 

[rickl]

Re: washington state wac rules

NONMETALLIC-SHEATHED CABLE NOT ALLOWED,except in one-and two-family dwellings.this is a quote from 2000 washington wac rules. maybe the city you were working in had there on rules. i've known a couple of apartment complexs that were wired with nmb but only after the contractor got the ok from the state. what happen ec bid 150 unit complex using nmb then found out he couldn't use it, he pention the state to change the rule or he was going to lose his butt and they did.

 

[dedbrk]

Re: washington state wac rules

Rickl, WAC 296-46B-334 is stating that type NM cable not allowed in any structure exceeding three floors above grade with the exception of one and two family dwellings. There is still many commercial occupancies that are being wired in NM cable without any noncompliance with NEC or WAC.