NFPA 13 Attic Sprinkler

[Jo_engineer]

I'm writing a paper on NFPA 13 Attic Sprinklers and am trying to gather information on why they are expensive and difficult to protect. Does anyone have a sense of how expensive it would be to protect say a 1000ft space above a theatre? What are the issues associated with this?

 

[MatthewJWillis]

An attic is a combustible space, with framing less than 3'-0" O.C., having a slope of 4/12 or greater.
Not sure a theater is wood framed?

The more specific criteria was added in the 2002 edition. Testing indicated the fire would basically rush right past the sprinklers and gather at the peak. Therefore, the spacing was adjusted to form sort of a wall..

Attic sprinklers require lots of water, several types, and different slope configurations.

Your system could be anywhere between $1,000.00 - $100,000.00.

R/
Matt

 

[cdafd]

Jo

Where do you get they are expensive?

Where do you get they are difficult to protect?

It is just either part of the building fire sprinkler system, or a designer may choose to have a separate system to protect the attic area only.

Just for your paper, trying to clarify the information you put into it.

 

[Jo_engineer]

Just researching online:

http://www.pmengineer.com/articles/89255-potential-pitfalls-of-unsprinklered-and-sprinklered-attics

I know there are freezing concerns, difficulty getting water up to the top of the building, etc.

 

[cdafd]

I am not an engineer or designer

I do not think that article supports your thesis.

Let's stick with a one story Building, even your theater with a higher roof, and simple rectangle attic.

If you build it in south Florida, you should not have a freeze problem. So a wet system could be used. Just extend the system in the theater and extend it into the attic area. You only required to maintain the pipe to 40 F.
You add the cost of pipe. You can use standard sprinklers or attic sprinklers.


Move the same project to Montana and you are more than likely going to do a dry pipe system. You will already have a water supply into the building. So add a dry pipe valve, compressor to the attic system you installed in Florida.

To me the only other issue, if you have a good water supply, is standard sprinklers of attic sprinklers.

Standard you will install more pipe in the attic.

Attic less pipe less labor.

Just think of it back to the one story example, adding attic protection, you basically have two floors of protection.


Check page 18 for these attic heads::
One line of pipe with sprinklers, attic done.

https://www.tyco-fire.com/TD_TFP/TFP/TFP610_08_2014.pdf

Just my non engineer thoughts. Attics can be hard depending on roof line layout, but when required to have protection, you are just adding another layer of pipe and sprinklers, like if you had a second floor.

 

[cdafd]

Maybe read through this to see if it adds to the discussion

http://www.tyco-fire.com/TFP_common/AtticSpecApp2.pdf

Add;::;

http://www.fireapparatusmagazine.com/articles/company-news/2016/07/tyco-attic-sprinklers.html

 

[TravisMack]

You have many variables to consider with attic protection:
Is it a flat / shallow attic requiring specially listed sprinklers and draft curtains?
Is it a slope of 4:12 or greater? That comes with a certain spacing requirement.
Is is wet or dry system?

You could be a wet system designed for 900 sq ft using small orifice sprinklers. Or, you could have a dry system that requires a 2535 sq ft design area with K5.6 sprinklers. As such, the costs vary as widely as those two criteria. Also, is it being built in Honduras or in San Francisco? That all has an impact on costs.

Travis Mack
MFP Design, LLC

http://www.mfpdesign.com

"Follow" us at

https://www.facebook.com/pages/MFP-Design-LLC/92218417692

 

[cdafd]

It could be said that a system for interior protection can get complicated and costly also.

The interior could wind up costing more than an attic system, in the same building.[pre][/pre]

 

[Jo_engineer]

Thanks for all the great info. What I'm trying to pin down are which types of attics are notoriously difficult to retrofit and why? I have some sense of the problems but no real sense of the extent of the difficulty and how widespread the issues.

 

[cdafd]

Ok now we are retrofitting.

You have a moving target.

Have not done to many attic retrofits. The ones I have done are normally half burned down if not more. So access for the sprinkler fitters is not much of a problem.

I go back to my last answer ::

"""It could be said that a system for interior protection can get complicated and costly also.

The interior could wind up costing more than an attic system, in the same building.""""


There are to many variables to your question.

To me it is not a good thesis topic is not good.

 

[MatthewJWillis]

"I have some sense of the problems but no real sense of the extent of the difficulty and how widespread the issues"


This is the very statement that can be applied to every attic that has ever crossed my desk. We simply do not know until presented with it.

I really wish there was a more specific answer.

Think of it this way, How much is a vehicle?

R/
Matt

 

[cdafd]

Plus

I am not on the saleing side so not sure if they do a complete break down of price.

Most of the time you do not install just an attic system.

So I guess you could add up all the sprinklers used in the attic, cost for all the pipe, and labor cost.

I am sure the companies have a few formulas to figure labor and material costs for different systems