# What are "Mechanical" Floors On Skyscrapers Exactly **URL:** \ **Category:** Factual Questions\ **Created:** [October 25, 2009, 8:26pm UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086 "2009-10-25T20:26:43Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Markxxx](https://avatars.discourse-cdn.com/v4/letter/m/5daacb/32.png) [@Markxxx](https://boards.straightdope.com/u/Markxxx)\ **Post date:** [October 25, 2009, 8:26pm UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086/1 "2009-10-25T20:26:43Z")
I was looking at the [Burj Dubai](http://en.wikipedia.org/wiki/Burj_Dubai), which is the world’s tallest building and the article tells what is on the different floors. Now I noticed the top 46 floors are used for “mechanical.” What exactly does that mean? I know buildings need floors dedicated to electricity and plumbing and a/c and heating and such, but why are so many at the top? Is it just a function to build the building to the world’s highest? Or is it that the building is so high no one would want to rent the floors so high up so they put the mechanics up there? Or perhaps in case of another terrorist attack there’d be less people up top? Here’s a breakdown of floor usage from the Wikipedia > [@](#): > > 160-206 Mechanical > 156-159 Transmission > 155 Mechanical > 139-154 Office > 136-138 Mechanical > 125-135 Office > 124 Observatory > 111-123 Office > 109-110 Mechanical > 76-108 Residential > 73-75 Mechanical > 43-72 Residential > 40-42 Mechanical > 19-39 Hotel > 17-18 Mechanical > 5-16 Hotel > 4 Hotel, Mechanical > 3 Hotel, restaurant > 2 Hotel, lobby > 1 Hotel, lobby, restaurant > Concourse Restaurant, lobby > B1-B2 Parking, Mechanical ---
**Author:** ![Harmonious\_Discord](https://avatars.discourse-cdn.com/v4/letter/h/74df32/32.png) [@Harmonious\_Discord](https://boards.straightdope.com/u/Harmonious_Discord)\ **Post date:** [October 25, 2009, 8:32pm UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086/2 "2009-10-25T20:32:10Z")
The machinery that is used to make the building livable is concentrated there. The top is a good place for much of it because of the vents are at the top. The water is at the top and gravity helps with the distribution. This includes fire suppression. There are some building with stabilization machinery in the top to counter wind and other forces. ---
**Author:** ![Harmonious\_Discord](https://avatars.discourse-cdn.com/v4/letter/h/74df32/32.png) [@Harmonious\_Discord](https://boards.straightdope.com/u/Harmonious_Discord)\ **Post date:** [October 25, 2009, 8:38pm UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086/3 "2009-10-25T20:38:27Z")
Let’s not forget the elevator equipment goes on top. Never forget the elevators.🙂 ---
**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\ **Post date:** [October 25, 2009, 8:44pm UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086/4 "2009-10-25T20:44:40Z")
Elevator machinery, electrical transformers, giant water tanks, boilers/furnaces, plumbing and heating distribution manifolds, phone line termination equipment, network routers/patch panels, building maintenance and security offices, and the big box of Christmas decorations. ---
**Author:** ![Dewey\_Finn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dewey_finn/32/4222_2.png) [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)\ **Post date:** [October 25, 2009, 8:55pm UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086/5 "2009-10-25T20:55:28Z")
> [@Harmonious\_Discord](#): > > Let’s not forget the elevator equipment goes on top. Never forget the elevators.🙂 Also, that floor plan mentions mechanical floors lower in the building, such as on the 17th and 18 floors. As the Wikipedia article mentions that the building has double-deck elevators, my guess is that these floors are for elevator lobbies. (So that you can take a double-deck express elevator to an upper level lobby and then a local elevator to the correct floor.) ---
**Author:** ![Sage\_Rat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sage_rat/32/399_2.png) [@Sage\_Rat](https://boards.straightdope.com/u/Sage_Rat)\ **Post date:** [October 25, 2009, 9:22pm UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086/6 "2009-10-25T21:22:49Z")
Um…like half the floors of the building are marked down as “Mechanical” according to your data. That sounds like something different. ---
**Author:** ![Markxxx](https://avatars.discourse-cdn.com/v4/letter/m/5daacb/32.png) [@Markxxx](https://boards.straightdope.com/u/Markxxx)\ **Post date:** [October 25, 2009, 9:27pm UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086/7 "2009-10-25T21:27:20Z")
Is there any reason why the top floors are mechanical though? I was just wondering about that more than anything. I know the latest trend in building tall buildings is to get them high and through the use of spires and such they can achieve this height without having to add any functionality. So I was thinking perhaps the reason there were so many “mechanical floors” was simply to increase the height of the building. That way instead of putting all the mechanical equipment on the lower floor that is bigger they could divide it up and put less on each floor and make the building taller. ---
**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\ **Post date:** [October 25, 2009, 10:32pm UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086/8 "2009-10-25T22:32:55Z")
Water tanks and elevator mechanics have to go on the top, so you might as well put other stuff there too. ---
**Author:** ![Harmonious\_Discord](https://avatars.discourse-cdn.com/v4/letter/h/74df32/32.png) [@Harmonious\_Discord](https://boards.straightdope.com/u/Harmonious_Discord)\ **Post date:** [October 25, 2009, 10:36pm UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086/9 "2009-10-25T22:36:31Z")
The reasons I gave are reasons for them to be near at the top. Water can’t be properly supplied from the lower floors only. I know there are films describing how come they are built how they are. Maybe a search for these is in order. ---
**Author:** ![Harmonious\_Discord](https://avatars.discourse-cdn.com/v4/letter/h/74df32/32.png) [@Harmonious\_Discord](https://boards.straightdope.com/u/Harmonious_Discord)\ **Post date:** [October 25, 2009, 10:43pm UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086/10 "2009-10-25T22:43:09Z")
I give up on the search. There is to much garbage in the results. ---
**Author:** ![runcible\_spoon](https://avatars.discourse-cdn.com/v4/letter/r/9fc29f/32.png) [@runcible\_spoon](https://boards.straightdope.com/u/runcible_spoon)\ **Post date:** [October 25, 2009, 11:19pm UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086/11 "2009-10-25T23:19:55Z")
Seriously, 40+ floors of mechanical? That sounds like either they’re using very broad terms, or there’s not a whole lot there. Or it’s COBRA’s secret command center. ---
**Author:** ![drachillix](https://avatars.discourse-cdn.com/v4/letter/d/48db29/32.png) [@drachillix](https://boards.straightdope.com/u/drachillix)\ **Post date:** [October 25, 2009, 11:37pm UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086/12 "2009-10-25T23:37:32Z")
> [@Harmonious\_Discord](#): > > There are some building with stabilization machinery in the top to counter wind and other forces. and those things are HUGE. > **[Tuned mass damper](https://en.wikipedia.org/wiki/Tuned_mass_damper)** > > A tuned mass damper (TMD), also known as a harmonic absorber or seismic damper, is a device mounted in structures to reduce mechanical vibrations, consisting of a mass mounted on one or more damped springs. Its oscillation frequency is tuned to be similar to the resonant frequency of the object it is mounted to, and reduces the object's maximum amplitude while weighing much less than it. > TMDs can prevent discomfort, damage, or outright structural failure. They are frequently used in power transm... The OP’s hotel has 11 of them ---
**Author:** ![Telemark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/telemark/32/372_2.png) [@Telemark](https://boards.straightdope.com/u/Telemark)\ **Post date:** [October 26, 2009, 12:09am UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086/13 "2009-10-26T00:09:31Z")
> [@runcible\_spoon](#): > > Seriously, 40+ floors of mechanical? That sounds like either they’re using very broad terms, or there’s not a whole lot there. Or it’s COBRA’s secret command center. Those top floors are pretty small. They might not be much use as office or residential space, but I bet they’d be fun. ---
**Author:** ![The\_Second\_Stone](https://avatars.discourse-cdn.com/v4/letter/t/bbe5ce/32.png) [@The\_Second\_Stone](https://boards.straightdope.com/u/The_Second_Stone)\ **Post date:** [October 26, 2009, 12:23am UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086/14 "2009-10-26T00:23:33Z")
Is there an observation deck or restaurant at the top? ---
**Author:** ![The\_Second\_Stone](https://avatars.discourse-cdn.com/v4/letter/t/bbe5ce/32.png) [@The\_Second\_Stone](https://boards.straightdope.com/u/The_Second_Stone)\ **Post date:** [October 26, 2009, 12:39am UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086/15 "2009-10-26T00:39:42Z")
I see in the wiki article that the 123rd (1444 feet and 440 meters) floor will be an indoor outdoor observation deck with 700 feet of spire still going up. ---
**Author:** ![Sage\_Rat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sage_rat/32/399_2.png) [@Sage\_Rat](https://boards.straightdope.com/u/Sage_Rat)\ **Post date:** [October 26, 2009, 4:52am UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086/16 "2009-10-26T04:52:29Z")
> [@Telemark](#): > > Those top floors are pretty small. They might not be much use as office or residential space, but I bet they’d be fun. Yes but those top 40 floors are not the only “mechanical” floors. Like I said in my post, the data that is provided in the OP seems to something like half of all floors in the building as being “mechanical”. ---
**Author:** ![Sunspace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sunspace/32/1250_2.png) [@Sunspace](https://boards.straightdope.com/u/Sunspace)\ **Post date:** [October 26, 2009, 5:12am UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086/17 "2009-10-26T05:12:58Z")
Accirding to the gang at SkyscraperCity, a lot of [those upper floors](http://www.skyscrapercity.com/showpost.php?p=25772920&postcount=10302) in the Burj Dubai are pretty small, being up in the spire. So azside from things like water tanks and the tuned mass damper, they’re probably antenna floors: transmitting equipment, weather sensors, etc. ---
**Author:** ![HongKongFooey](https://avatars.discourse-cdn.com/v4/letter/h/c4cdca/32.png) [@HongKongFooey](https://boards.straightdope.com/u/HongKongFooey)\ **Post date:** [October 26, 2009, 5:22am UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086/18 "2009-10-26T05:22:08Z")
> [@runcible\_spoon](#): > > Seriously, 40+ floors of mechanical? That sounds like either they’re using very broad terms, or there’s not a whole lot there. Or it’s COBRA’s secret command center. Just a WAG. I’m not sure if it would be the same type of thing but anyone who’s had to do work in a hospital has probably been in one of those little crawlspace type floors in between the main floors. They’re not even big enough to stand up in, they are hot and cramped and full of pipes and conduit and various things but they provide better access to various lines and runs than would otherwise be available. Maybe in this building they assigned numbers to those types of floors where in other buildings they aren’t given separate numbers like that except on a service elevator maybe. ---
**Author:** ![fiddlesticks](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/fiddlesticks/32/18129_2.png) [@fiddlesticks](https://boards.straightdope.com/u/fiddlesticks)\ **Post date:** [October 26, 2009, 3:31pm UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086/19 "2009-10-26T15:31:09Z")
> [@The\_Second\_Stone](#): > > I see in the wiki article that the 123rd (1444 feet and 440 meters) floor will be an indoor outdoor observation deck with 700 feet of spire still going up. The _Amazing Race_ put a cluebox on what looked like the under-construction 123rd floor observation deck two episodes ago. After reading about the construction standards in the UAE, I’m not sure if I want to ever get within blow-over range of this building… ---
**Author:** ![qazwart](https://avatars.discourse-cdn.com/v4/letter/q/5fc32e/32.png) [@qazwart](https://boards.straightdope.com/u/qazwart)\ **Post date:** [October 27, 2009, 3:51am UTC](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086/20 "2009-10-27T03:51:32Z")
Usually, the 13th floor is reserved for mechanical stuff in very tall buildings. I was surprised by your layout that the 13th floor is being used for a hotel. [Next page](https://boards.straightdope.com/t/what-are-mechanical-floors-on-skyscrapers-exactly/515086.md?page=2)