13R systems, residential sidewalls and standard QR sidewalls.

[SprinklerDesigner2]

As an example let's use Vikings VK460 residential horizontal sidewall sprinkler [URL unfurl="true"]http://www.vikinggroupinc.com/sites/default/files/documents/110205_0.pdf[/url]

If I have been interpreting this incorrectly over the years then at least I never did anything wrong.

We have an existing care home that requires retrofit and there isn't a space above the ceiling we can place our heads. Everything will have to be exposed below the ceiling so we're looking at exposed steel pipe.

The way I read the cut sheet is you must use the escutcheon as it is part of the listing and places the sprinkler a minimum of 1 3/16 and a maximum of 2 3/8" off the face of the wall or soffit.

Of course the distance down from the ceiling is a minimum of 4" and a maximum of 12".

The way I have always interpreted it is I can not simply run an exposed line placing my sprinklers 4" to 6" off the wall as allowed by NFPA #13 because we are not in NFPA #13.

The only way I can see doing this is run the line behind the wall doing whatever it takes to penetrate and place the escutcheon or install a soffit.

6.2.1.3 Listed quick-response sprinklers shall be permitted to be installed in dwelling units meeting the definition of a compartment, as defined in Section 3.3, where no more than four sprinklers are located in the dwelling unit.

Can't use that; the entire house is a single dwelling unit. Trying to push it so each bedroom is a separate dwelling unit is just hoodoo to me...

But if we wanted to use quick response sprinklers we could but we would have to go to NFPA #13 and all it entails. Density, attic sprinklers and everything else that goes along with it.

Am I right? (I think I am 100% correct but just wanting to make sure).

Thanks

 

[skdesigner]

Sounds like you are right to me. Depending on how much emphasis your client is putting on aesthetics vs. cost, Viking does make a residential upright (VK467) that works well in these situations.

 

[cdafd]

If the pipe is ran exposed, why do you need the eschution??

Call Viking tech and ask the question??

 

[cdafd]

VK460 horizontal sidewall sprinkler deflector shall be located a minimum of 1-3/8“ (35 mm) and a maximum of 6” (152 mm) from the wall on
which it is installed.

 

[SprinklerDesigner2]

I am not so sure. That is under "For systems designed to NFPA 13: ..."

Does that apply to 13R?

I guess I will call Viking tomorrow just to make sure.

 

[MGXFP]

Well, each dwelling unit is probably a compartment according to the definition in Chapter 3.

I have had to use this criteria for an EC HSW in a residential concrete building where the chance to add sprinklers in adjacent walls was not an option so 13 criteria was used because the commercial EC HSW 10 years ago threw further than residential EC HSW.

I would also check the occupancy if R or I to make sure 13R is OK but I know you did that already.

 

[SprinklerDesigner2]

I always check and I always insist the professional of record gives me the appropriate standard to use in writing.

As I explain to the architect I am not an architect or professional engineer. I am not competent to make such a decision and if I tried to assign a standard I would be practicing architecture without a license.

What architect would possibly disagree with me especially when such correspondence is relayed through the owner? I always get an answer back and I really don't care if it is right or wrong because I don't have a dog in that fight.

Had this happen once. The architect has 13R on his signed and sealed drawings but I smelled something wrong so simply asked the question. The professional of record claimed it was a 13R system when it wasn't. The owner was very upset but not upset with me. The worst thing a layout technician can do is play architect or professional engineer.

The building is concrete, can not run heads in the ceiling and the large living room will take a minimum of 6 sprinklers in the compartment.

I need to call Viking.

 

[MGXFP]

What I was getting at is one can use listed, QR commercial sprinklers that are not residential sprinklers in a residential scenario. It follows they must be calculated differently than residential sprinklers.

skdesigner above mentioned residential uprights. They might be a good option for this application. Just be aware residential uprights/pendents must have deflectors 1-4" below the ceiling.

Is there a finished ceiling?

 

[SprinklerDesigner2]

Yes, a finished drywall ceiling so no problem there. With QR commercial sprinklers once you go over four heads in a "dwelling unit" you are forced to leave 13R and go with 13 which means attic sprinklers.

What we have is an existing standard ranch home with five bedrooms just like the house you might live in. The entire house is a dwelling unit and in my opinion to call each bedroom a separate dwelling unit is pushing it to hard.

That is how I've always interpreted it.

 

[MGXFP]

That makes sense. I rechecked NFPA 101 and NFPA 13 which I think Georgia enforces and dwelling unit is kinda the whole building. I'm used to the term in reference to hotels and motels which is much easier to implement.

Interestingly the QR requirement came about as a compromise with the lodging industry that wanted to retrofit lots of buildings in the '80s and EC HSW sprinklers being the easiest way to do this lacked the residential listing. NFPA allowed the use of QR sprinklers but limited them to 4 in a dwelling unit. I guess this explains why I was confused earlier; I've only ever applied this to hotels and motels which is exactly what this exception is designed for!

To sum up I think you are correct. I have done layout for systems like this before using pipe penetrating the walls and decoshield on the side with the pipe. I'm not aware of any residential sidewall that lets the deflector be that far off the wall to run the pipe in the same compartment as the sprinkler it serves. Looks weird but meets code. Another option is to build an 8" or less soffit.

 

[SprinklerDesigner2]

NewtonFP,

What I heard was way back yonder the standard allowed for four QR heads in dwelling unit so standard QR dry pendents and dry systems could be used on the upper floors motels in areas of the far north where it really freezes.

Before I would use a residential sidewall without an escutcheon I would need it in writing from the manufacturer that is was OK to do. Lacking that I would do it a way I knew was right even if it looked bad.