Fire Suppression 2

8m 15s

In this ARE 5.0 NCARB-approved Project Planning and Design Exam Prep course you will learn about the topics covered in the ARE 5.0 PPD exam division. A complete and comprehensive curriculum, this course will touch on each of the NCARB objectives for the ARE 5.0 Project Planning and Design Exam.

Instructor Mike Newman will discuss issues related to the generation or evaluation of design alternatives that synthesize environmental, cultural, behavioral, technical and economic issues.

When you are done with this course, you will have a thorough understanding of the content covered in the ARE 5.0 Project Planning and Design Exam including design concepts, sustainability/environmental design, universal design, and other forms of governing codes and regulations. 

So we've been talking about specialty systems like fire suppression systems and sprinkler systems and all the things that go with that. The standpipes and the fire pump rooms which might have multiple fire pumps and even a few electrical backup systems. So I've got lot of things happening in there. Generators and all that. So we've got all these things going on. And it's interesting to sort of put this into a little bit of context. If you've spent any time in any of the older cities around the United States, you've probably sort of wondered, looked up at the sky and seen those old water tanks up on the old buildings.

So you have a bunch of great big buildings with big water tanks up on the roof. What's that about? Well it does two different things, actually three different things. One possible thing that it does is, if I have a water main in the street, that water main is going to be under pressure. And so when I tap off of that into my building, I'm going to have pressure in my building solely because the water main is already under pressure.

But it's only under pressure to such a degree that it'll push the water up to the second floor pretty easily usually, first floor certainly, and maybe the third floor, possibly the fourth floor. But it's likely to not push it up any higher than that. So one of the ways, sort of old school ways, of doing this is you would then have a very small pump or just use a very low-level pressure that it will allow and push water up to this tank up on the roof.

And that's going to pressurize all of your sinks and toilets and all of those. It's gonna, by lifting that water up, and I can do it all night and then let it come down. So I don't have to have the system that's filling the tank be a very robust system at all. It can just be a little, tiny sort of pumping system. And just fill it all the way up.

And then that creates pressure for my potable water system. So that's one of the things that those tanks are doing. The other thing that those tanks are doing though, the thing that's really important from the city's standpoint, is that they provided a reservoir of water. And that reservoir of water, first of all, if something went drastically wrong in the city, if there was suddenly a situation where the water got contaminated or if the power went out in the city so nobody had the ability to get water pumping, well then that building has its own sort of pressurized system.

And you could live off that water for a few days. So you'd have people have access to fresh water. They'd have the ability to cook and kind of keep themselves sort of reasonably clean and sanitary, to flush away the toilets and things like that. So you're not creating an unsanitary situation. So having that tank of water is a big advantage in that kind of a situation.

And then the third thing that those tanks were doing is that, in the same way that we had the tank pressurizing our potable system, it also probably was used to pressurize the fire suppression system. So we have a bunch of sprinklers that can spread around the building. And instead of them being pressurized from water coming from the street, they get pressurized by this big tank that's sitting up at the top.

And if we need a whole bunch of water, that water can go for quite a while. It's a lot of water up in one of those tanks. And it will spread down through the building and move out into the space and through the sprinkler. So those old tanks were kind of this great low tech way, all you had to do was just get enough water that it would fill up the tank eventually, and then you just keep topping it off over time. And as you use a little bit, you top it off, as you use a little bit, you can keep topping it off so you always have that full tank.

But then if I have this big need for emergency reasons or for just pressure reasons, then I have that water available to me. There's obviously a couple problems with having those tanks up on the roof. One is there's this huge, heavy tank up on the roof, there's a big structural issue there and that's a big problem for these things, that the buildings have to withstand this massive big load of this big thing of water up on the roof.

So that's one of the problems. The other problem is you have this big tank on the roof that's getting ice and snow on it, it's freezing, the pipes are freezing, the solar gain in the summer with the UV rays, it's treating the wood difficultly, there's expansion and contraction from the hot sun. All these different difficulties about being up on the roof, it's a very hard place to be 'cause it's getting the most wind, the most snow, the most UV rays because it's not shaded by anything, it's way up high.

So that tank is very hard to maintain. So generally, over the last 30 years or so, most cities have seen all those big old tanks starting to go away or empty out, so they might be still sitting there, but they're probably not using them anymore and they're now going to these more straightforward systems of having, instead of a big tank up on the roof, having a big fire pump room in the basement with a big fire pump in it, possibly a booster pump for the potable water as well, and finding ways to pressurize that system instead of from the tank, they're doing it through the pumps.

The obvious problem with that, and the reason that I have a very fond feeling towards those tanks is there's something really beautiful about the idea that these tanks can pressurize these systems off of such a low tech simple way. And you imagine in an emergency, what's the first thing that's gonna go?

Well, it's gonna be the power. What do we need in order to make the water work? Power for the pumps. So not only do I need pumps, that pumps break and fail and need to be maintained, but now I need to have the backup generators, and backup generators break and fail and need to be maintained. When are you gonna test your backup generators? Well, the way you're gonna find out that it's not working is an emergency happens and you kick them on and they don't go on.

Or it turns out that nobody ever replaced the gas after the last time or whatever it happens to be. So the new systems make sense for lots of reasons. And there's, I'm sure, a lot of thought that has gone into it. But it is sort of a sad state that those beautiful old tanks that were up on these roofs that answered all of these issues so straightforwardly and in such a low tech way, it is sort of sad that they're all going away. You will still see in certain settings these large tanks up on the roof.

Not usually as exposed as the old school ones, but in different settings. Especially if you go in different parts of the world where the electrical is not always so, you can't count on the electrical quite so much, so the systems will pump up water up onto the roof so you'll always have at least some potable water, and that way you can kind of live by a power outage of an hour or two or five hours or something.

And everybody just knows to be a little careful with the water when the power goes out. So you will see it in certain parts of the world and certain parts of the country, but essentially, they've been going away for all those reasons that we said. So it's sort of sad, same time, this is the realization you either have to figure out a way to make that work and make those tanks work in order for that to answer all of those issues, or you've gotta make space for the stand pipes, for the fire pumps, for the backup generators, and all those other things that you would need in order to have a system that works no matter what problem comes at you.

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From the course:
ARE 5.0 Project Planning & Design Exam Prep

Duration: 31h

Author: Mike Newman