Building Construction Type

[Tom Drake]

I'm trying to determine if I can install NM cable in a multifamily building. It is a 4 plex - two story. Concrete walls and ceiling. I am told if it is all concrete. I can not. Is there an easy determination between Types I II III IV and V construction types.

 

[GoldDigger]

I'm trying to determine if I can install NM cable in a multifamily building. It is a 4 plex - two story. Concrete walls and ceiling. I am told if it is all concrete. I can not. Is there an easy determination between Types I II III IV and V construction types.

Yes, using the definitions in the Building Code.
But many read that section of the NEC as depending on what the construction is required to be, rather than what it is.

 

[iwire]

Take a look in the rear of the NEC at "Informative Annex E Types of Construction" and that may help you.

Keep in mind the NEC rules are not based on how the building was constructed but how it could be allowed to be constructed.

In other words you can treat a steel and concrete building as a wood framed building if the building codes would have allowed it to be built with wood.

 

[Strathead]

I'm trying to determine if I can install NM cable in a multifamily building. It is a 4 plex - two story. Concrete walls and ceiling. I am told if it is all concrete. I can not. Is there an easy determination between Types I II III IV and V construction types.

Usually (always in this state) you will find this information on one of the front pages of the Architectural plans. Often entitled, "Building information" It will likely include square footage, square footage allowed, whether the building is sprinkled, has fire alarm, etc. Sometimes found on the Life safety plan but more often the first page or the first page after the cover/index.

 

[iwire]

Usually (always in this state) you will find this information on one of the front pages of the Architectural plans. Often entitled, "Building information" It will likely include square footage, square footage allowed, whether the building is sprinkled, has fire alarm, etc. Sometimes found on the Life safety plan but more often the first page or the first page after the cover/index.

I agree it has a lot of info including building type but isn't that the building type being constructed not necessarily the building type allowed?

 

[Strathead]

I agree it has a lot of info including building type but isn't that the building type being constructed not necessarily the building type allowed?

i dislike the fact you can't just cut and paste a pic in to a post. I don't know what you are asking, but the information is the exact information you need to determine NEC requirements. Another piece is like the one I am looking at. Occupancy class, Assembly - Arena A-4 So I am subject to article 518.

 

[iwire]

i dislike the fact you can't just cut and paste a pic in to a post. I don't know what you are asking, but the information is the exact information you need to determine NEC requirements. Another piece is like the one I am looking at. Occupancy class, Assembly - Arena A-4 So I am subject to article 518.

What I am pointing out is just because a building is made out of concrete and steel and indicates that building type on the prints that may not be enough to know if you can run NM.

A builder can choose to use concrete and steel even though the building code allows wood construction. In that case the NEC allows NM.

 

[mgookin]

What I am pointing out is just because a building is made out of concrete and steel and indicates that building type on the prints that may not be enough to know if you can run NM.

A builder can choose to use concrete and steel even though the building code allows wood construction. In that case the NEC allows NM.

Exactly.

When I did plan review (for decades) most good plan sets had a "Building Code Analysis" table on or near the cover sheet. One of the elements of that table is "Construction Type" and there would be a column for "Required" and another column for "Provided".

It is the "Required" column that applies to the use of NM.

OP:
Table 500 in the FBC allows that building to be of Type V construction. You should be fine pulling NM, but don't do it because I said so. Run it by the plans examiner & electrical inspector for the jurisdiction.

 

[GoldDigger]

...
OP:
Table 500 in the FBC allows that building to be of Type V construction. You should be fine pulling NM, but don't do it because I said so. Run it by the plans examiner & electrical inspector for the jurisdiction.

And also, if it seems appropriate, let the owner know that using NM is allowed but might reduce the good fire rating he is getting from his fire insurance company.

 

[iwire]

And also, if it seems appropriate, let the owner know that using NM is allowed but might reduce the good fire rating he is getting from his fire insurance company.

Do you have any reason to say that or is it a guess?

 

[mgookin]

And also, if it seems appropriate, let the owner know that using NM is allowed but might reduce the good fire rating he is getting from his fire insurance company.

It's in Florida. He's already screwed! :lol:

 

[gadfly56]

What I am pointing out is just because a building is made out of concrete and steel and indicates that building type on the prints that may not be enough to know if you can run NM.

A builder can choose to use concrete and steel even though the building code allows wood construction. In that case the NEC allows NM.

So Thomas Edison's "Concrete House" could be wired with NM if built today, all other things being equal?

 

[GoldDigger]

Do you have any reason to say that or is it a guess?

Total and absolute speculation, but based on the sort of questionaire and inspection done for residential insurance.
Each company has its own actuarial "things" for evaluating coverage.

For example, if INSCO asks what the building construction type IS rather than is required to be, putting in the NM might change the answer to that question.

 

[raider1]

Keep in mind the NEC rules are not based on how the building was constructed but how it could be allowed to be constructed.

In other words you can treat a steel and concrete building as a wood framed building if the building codes would have allowed it to be built with wood.

I would be very careful going down that road.

If, as an Owner of a building, I choose to build my building as a Type II Building so I have the flexibility to change occupancy groups in the future I would want that building wired as a Type II building even if the building could be built as a type III, IV or V.

Chris

 

[GoldDigger]

I would be very careful going down that road.

If, as an Owner of a building, I choose to build my building as a Type II Building so I have the flexibility to change occupancy groups in the future I would want that building wired as a Type II building even if the building could be built as a type III, IV or V.

Chris

A very good point, but more an issue for job specifications and Value Engineering than an NEC issue.

 

[iwire]

I would be very careful going down that road.

If, as an Owner of a building, I choose to build my building as a Type II Building so I have the flexibility to change occupancy groups in the future I would want that building wired as a Type II building even if the building could be built as a type III, IV or V.

Chris

For many years we wired cement and steel buildings with NM specifically because that is what the customer wanted. The least costly method. This pretty much stopped when the prohibition for NM above dropped ceilings came into effect.

In the OPs case it is a muiltifamily those don't usually change into something else.

But regardless it would be worth running by the person paying the bills

 

[iwire]

Total and absolute speculation, but based on the sort of questionaire and inspection done for residential insurance.
Each company has its own actuarial "things" for evaluating coverage.

For example, if INSCO asks what the building construction type IS rather than is required to be, putting in the NM might change the answer to that question.

Thanks.

 

[raider1]

For many years we wired cement and steel buildings with NM specifically because that is what the customer wanted. The least costly method. This pretty much stopped when the prohibition for NM above dropped ceilings came into effect.

In the OPs case it is a muiltifamily those don't usually change into something else.

But regardless it would be worth running by the person paying the bills

I agree in the OPs case it most likely won't be a issue.

As a Building Official I have seen instances where changing an Occupancy type can be affected by Construction Type.

For example if I had a 9,000 square foot office building single floor non-sprinklered it could be built as a VB Building made of wood. But if I wanted to change the building to an any-time fitness gym which is an A-3 then I am limited to 6,000 square feet as a VB wood building but if it was a Type IIB then I could go as large as 9,500 square feet.

Chris