That would be a nice little detail. All you see on the outside is the actual connectios, and not a standpipe. I'm sure you all have seen them, the brass fittings on the outside of a multistory building. Some buildings have a combination standpipe and sprinkler connection, and some buildings have a seperate connection for each. They will be right next to each other.
The local FD's SOP will determine which one to hook up to first. The visible part of the stand pipe is found in the staircases of the building, with a hose connection at each floor.
Mike.
My You Tube
Guys,Ray brings out some interesting information and points out a detail we modelers overlook on the outside of our industrial buildings-the stand pipes.
Thanks Ray! I now have a excellet detail idea for my Walthers background buildings.
Larry
Conductor.
Summerset Ry.
"Stay Alert, Don't get hurt Safety First!"
Ray,
Thanks for the Cliff's Notes version of THAT...but people now know where to find more info on this, too.
Mike Lehman
Urbana, IL
It's all about fire insurance. The reason we have access to all those wonderful historic Sanborn maps is to determine fire insurance ratings.
I just completed design of a fire suppression system and emergency diesel fire pumps and building for a large power plant in Northern Nevada. I'm a registered civil/mechanical engineer, but the field is so specialized that I had to work with one of our registered fire protection engineers on specific code issues.
A building's fire demand (flow and duration) is a function of occupancy, size, material of construction, exposure, srinklers, etc. The demand can easily exceed 5,000 gallons per minute (gpm) for two hours. Most public water supply systems are only required to provide 1,500 gpm, so the facility has to make up the difference from on-site storage. For large storage requirements, the tank is usually at ground level and diesel fire pumps are used. For smaller storage requirements, a roof top tank and gravity feed might be better.
The fire pumps or the tank supply the building's fire suppression standpipes which connect to the interior hose outlets and sprinklers. The standpipe system can be either "wet" or "dry". There is usually a Fire Department Connection (FDC) on the exterior of the building. The FDC allows the fire department to connect their pumper hose to a nearby fire hydrant and connect discharge hoses between the pumper truck and the FDC. That lets them boost the pressure/flow in the standpipe. The fire suppression standpipe system is not connected to any of the other building plumbing.
All the requirements are spelled out by NFPA (National Fire Protection Association) and Factory Mutual.
Ray
I think that in many cases, water pressure and fire suppression are both covered by rooftop tanks. One need is 24/7 and the other is "I really hope not" but fires on the upper floors require lots of water, so they can act to supplement water pressure to ensure that.
Many tall buildings also have a fire supply system plumbed down to the street so that a pumper truck can hook up to add to the building's internal supply in case of emergency.
Do we have any plumbers in the house to help explain how this all works together? I'm pretty sure the two in the first paragraph are linked (with suitable backflow valvling, etc) but the street-to-roof fire supply system is totally separate, IIRC.
Although the majority of water tanks were there for the everyday use of the people in the building, there were some early (c.1900) skyscrapers that were built with rooftop tanks for fire suppression. The problem was that buildings got taller than fire hoses could reach. The concept was that, in case of a fire, they could somehow release the water in the tank and it would pour over the building to put out the fire - kind of like "The Towering Inferno" movie from the 1970's.
Not sure if it ever was attempted, or if it worked if it was tried. I would think the water would just run over the side of the building. My guess is pretty quickly it was realized the water in the tank could be connected to a sprinkler system instead. BTW since the water was on the roof, gravity could force the water through the sprinklers even if the fire had damaged the electrical / water pumping system.
I can remember when I'd see many wood water tanks on the roofs of older warehouse and industrial district type structures in Milwaukee. But what I recall is that most were of fairly modest size, and some were downright small. In his kitbashing book the late Art Curren sometimes used N scale water tanks for the roofs of his HO buildings.
Dave Nelson
Although I am from the NY metro area, and I am quite familar with the famed wooden water tanks of NYC (I think Mike Rowe on a 2008 Dirty Jobs episode helped rebuild such a wooden water tank), building water tanks can take on many forms, including just cylindrical metal tanks on the roof.OK, for those of you not familiar with the many "Factoid" YouTube channels out there, the reason for the image of the young Asian woman on the right side of that linked picture: She is Elisa Lam, and in a tragic mystery she was found dead a few years ago in Los Angeles, in those very hotel water tank pictured on the left side of the image. Yes, her body was only discovered after the guests started to complain about the odd smell & taste of their water.
BigDaddyI suppose it is one of water pressure and plumbing back in the day. You might have great water pressure in your home, but imagine if there were 7 floors above you. The guy on the 8th floor might only have a trickle. It was probably technolgically easier to pump it into a tank on the roof and distribute it by gravity rather than pump it to each floor and do that so it was adquate on the 8th floor and wouldn't blow out the pipes on the ground floor. Today the technology exists to supply 100 story buildings but tanks are still in use:
You are correct.
I tried to sell my two cents worth, but no one would give me a plug nickel for it.
I don't have a leg to stand on.
DSchmitt beat you to it, Henry. He has the same link in his post, above yours, plus a couple of others.
Where I worked in 1967-68 our building had a moderate size tank on the roof to give an iintial water supply to the sprinkler (fire) and Safety Showers (chemical mishap).
This was never used in the year I was there.Hopefully it never was. But some one must have thought the original cost was worth it.
Dave
Interesting question. I remember many tanks growing up in the 50's around Baltimore. The whole city burned down in 1904 so they came after that.
I suppose it is one of water pressure and plumbing back in the day. You might have great water pressure in your home, but imagine if there were 7 floors above you. The guy on the 8th floor might only have a trickle. It was probably technolgically easier to pump it into a tank on the roof and distribute it by gravity rather than pump it to each floor and do that so it was adquate on the 8th floor and wouldn't blow out the pipes on the ground floor.
Today the technology exists to supply 100 story buildings but tanks are still in use:
http://www.amny.com/real-estate/city-living/water-towers-nyc-s-misunderstood-icons-1.6982696
Henry
COB Potomac & Northern
Shenandoah Valley
Here is an article about rooftop water tanks in New York.
City of Chicago rules for rooftop water tanks http://www.cityofchicago.org/city/en/depts/bldgs/supp_info/roof-top-water-tank.html
Water Supply in Tall Buildings http://www.pacopumps.com/Documentation/WhitePapers/Roof_Tank_Whitepaper.pdf
Hi
I have seen many models and pictures of layouts that show older structures that have huge water tanks on the roof of the structures. Why were these water tanks needed? What was the time frame that they were in use? How do you determine whether or not a water tank would be appropriate for an industry that you want to place on your layout? I am working in HO during the transition from steam to diesel. Thanks for your help.
wdcrvr