Rommex Installation

[Dennis Alwon]

Yes everything past the framing and its sheathing is outside. Exterior sheating has an inside and outside.

If the NM is 'protected from the weather' (outside) this is a damp location. Violation of 334.

Yes I use more than the NEC. Sorry about your blood pressure.

What do crawl spaces have to do with the discussion at hand?

If the OP's question was NM stapled to the outside of sheathing, and we do not know if this was his question, it is a violation to install it there.

The crawl space has everything to do with it since the wiring is often below the framing in a damp area.

Tell me how water gets under the siding any more than it would in the wall. NM can be fastened to the cinder block wall.

If you have a shed with no insulation and run the wires in walls do these walls need UF cable? Suppose there wasn't any sheathing but diagonal 2x4 framing would you require UF cable or the like?

 

[jxofaltrds]

The crawl space has everything to do with it since the wiring is often below the framing in a damp area.

Tell me how water gets under the siding any more than it would in the wall. NM can be fastened to the cinder block wall.

If you have a shed with no insulation and run the wires in walls do these walls need UF cable? Suppose there wasn't any sheathing but diagonal 2x4 framing would you require UF cable or the like?

This is from a couple of weeks ago. Water entering the stucture around the J channel.

 

[Dennis Alwon]

This is from a couple of weeks ago. Water entering the stucture around the J channel.

That is fine but that doesn't mean you make the rules. In the case we were talking about the siding would be on the furring strips and the wire would be 3/4" or more from the sheathing or siding. I don't see the issue or the code to support your claim.

 

[jxofaltrds]

That is fine but that doesn't mean you make the rules. In the case we were talking about the siding would be on the furring strips and the wire would be 3/4" or more from the sheathing or siding. I don't see the issue or the code to support your claim.

You are correct. I do not make the rules. NM can not be used under the siding per 334.12(B)(4).

 

[ike5547]

You are correct. I do not make the rules. NM can not be used under the siding per 334.12(B)(4).

If "under the siding" is "exposed or subject to excessive moisture or dampness," they'll be tearing the siding off to repair dry rot long before the romex is affected.

 

[jxofaltrds]

If "under the siding" is "exposed or subject to excessive moisture or dampness," they'll be tearing the siding off to repair dry rot long before the romex is affected.

From: http://www4.iccsafe.org/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=4;t=007118#000003



The proper application of a weather resistive barrier is a very important component of the wall and is a building code requirement for walls constructed using plywood or OSB sheathing.

I understand that the question is based on the 2001 California Code (UBC) but the most current code development is based on improved industry knowledge and shouldn?t be overlooked.

Reference 2004 IBC and IRC Supplements:

IBC Section 1404.2: "Water-resistive barrier. A minimum of one layer of No. 15 asphalt felt, complying with ASTM D 226 for Type1 felt, shall be attached to the studs or sheathing, with flashing as described in Section 1405.3, in such a manner as to provide a continuous water-resistive barrier behind the exterior wall veneer."

IRC Supplement Section R703.2: "Weather-resistant sheathing paper. One layer of No. 15 asphalt felt, free from holes and breaks, complying with ASTM D 226 for Type1 felt or other approved weather-resistive materials shall be applied over studs or sheathing of all exterior walls. ?" The section goes on to describe acceptable application referring to Table 703.4 and certain limited exceptions.

"Exceptions: Omission of such felt or material is permitted in the following situations:
1. In detached accessory buildings.
2. Under exterior wall finish materials as permitted in Table R703.4
3. Under paperbacked stucco lath when paper backing is an approved weather-resistive sheathing paper."

IRC Supplement Table R703.4 stipulates that a weather resistive barrier is required under vinyl siding. Footnote m. of the table states, ?Vinyl siding shall comply with ASTM D 3679.?

Both APA The Engineered Wood Association (APA) and the Vinyl Siding Institute (VSI) recommend weather resistant barriers.

The "Build a Better Home" section of APA's website, http://www.apawood.org, provides recommendations to help assure moisture protection. APA's publication on walls addresses the proper use of weather-resistant barriers. It is available online at: http://www.apawood.org/level_c.cfm?...es&pD=Yes&pF=Yes&CFID=114470&CFTOKEN=21646285

In their paper "VSI Weather Resistant Barrier Statement" VSI states, "Vinyl siding has always been designed as an exterior cladding, not a weather resistant barrier. Vinyl siding is designed to allow the material underneath it to breathe; therefore, it is not a watertight covering. Because of its design and application, it provides a supplemental rain screen that enhances the weather resistant barrier system by reducing the amount of water that reaches the underlying weather resistant barrier." The entire VSI paper is available online at: http://www.vinylsiding.org/vsic/VSIWeatherResistantBarrierStatement.pdf



We are always happy to assist with questions related to engineered wood, southern pine or SIP product's. Available weekdays 7 AM to 5 PM (Pacific).

APA and Southern Pine Council Help Desk
Tel: 253-620-7400
E-mail: help@apawood.org

 

[ike5547]

Looks like you've made your point. I assume if vinyl siding needs to "allow the material underneath it to breathe," and so "therefore, it is not a watertight covering" other forms of siding do as well. So, on this technicality NM would not be allowed, supposedly.

 

[Dennis Alwon]

You are correct. I do not make the rules. NM can not be used under the siding per 334.12(B)(4).

And yet you fail to answer my questions about the crawl space and accessory buildings... You got the power to do what you will but I must say I really think you are fishing-- I am glad you are in Ohio.

 

[jxofaltrds]

And yet you fail to answer my questions about the crawl space and accessory buildings... You got the power to do what you will but I must say I really think you are fishing-- I am glad you are in Ohio.

NM allowed in the crawl and in the accessory buildings. I never questioned that.

 

[Dennis Alwon]

NM allowed in the crawl and in the accessory buildings. I never questioned that.

And this is okay, in spite of the fact that it is damp in most crawl spaces and basements

 

[ike5547]

And this is okay, in spite of the fact that it is damp in most crawl spaces and basements

That's true. By the same logic, attic spaces are not water tight. They are allowed to breathe. There are all sorts of openings to the exterior. Water molecules are allowed to enter.

In fact, water molecules are everywhere.

Therefore: NM should be banned.

 

[Dennis Alwon]

Therefore: NM should be banned.

Or just not get bent out of shape about it being in a damp location. I have seen NM underground that was there for 20 years and still working-- Please understand I don't condone that type of work but I won't worry about NM being installed behind siding, etc.

 

[ike5547]

Or just not get bent out of shape about it being in a damp location. I have seen NM underground that was there for 20 years and still working-- Please understand I don't condone that type of work but I won't worry about NM being installed behind siding, etc.

I think there may be a cognitive disconnect between what a siding manufacturer considers damp and what the NEC does. The code says "excessive dampness" not water molecules in ppm.

 

[jxofaltrds]

I saw NM hanging from a tree at a party last night. Worked fine. The problem is it is not allowed.

 

[ike5547]

I saw NM hanging from a tree at a party last night. Worked fine. The problem is it is not allowed.

I'm sure no one will disagree with that.

 

[jxofaltrds]

I'm sure no one will disagree with that.

We will wait and see.

 

[ike5547]

We will wait and see.

Maybe they were just using it as a rope swing.

 

[Dennis Alwon]

I saw NM hanging from a tree at a party last night. Worked fine. The problem is it is not allowed.

Mike, well since it is temp. maybe someone will disagree but that is not the point. You seem to be adamant about nm not being allowed in a damp location and calling the area behind the siding a damp location but yet you will allow nm in a damp crawl space. You are not consistent or being realistic , IMO.

I agree NM is not allowed in a damp area but we differ on what a damp location is defined as. Look at a definition of dry location.

Location, Dry. A location not normally subject to dampness or wetness. A location classified as dry may be temporarily subject to dampness or wetness, as in the case of a building under construction.

Just because a building under construction is an example it is not the only one. So you must think that behind the siding is always damp and / or wet.

 

[jxofaltrds]

Mike, well since it is temp. maybe someone will disagree but that is not the point. You seem to be adamant about nm not being allowed in a damp location and calling the area behind the siding a damp location but yet you will allow nm in a damp crawl space. You are not consistent or being realistic , IMO.

I agree NM is not allowed in a damp area but we differ on what a damp location is defined as. Look at a definition of dry location.



Just because a building under construction is an example it is not the only one. So you must think that behind the siding is always damp and / or wet.

Dennis

Yes I am adamant about it. While a crawl may be damp, the NEC does not call it damp nor do I see that I can call it damp. There is no standard, like a % of moisture, for me to use.

Siding is an exterior covering (Chapter 7 of The Residential Code). It is applied to the outside of the structure. 334 NEC does not allow NM outside.

NM is not allowed to be installed in a structure until it is protected from the weather.
R701.2 Installation.

Products sensitive to adverse weather shall not be installed until adequate weather protection for the installation is provided. Exterior sheathing shall be dry before applying exterior cover.

So even if you wanted to install it under the siding, how could you meet the above code?

Yes the wire would probably out live us but that does not make it code compliant.

 

[iwire]

Mike, it is your opinion firing strips are OK to be used outside?