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#### bluejay1

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We have a small roof deck - about 20' x 15' over two steel beams, on top of a
small brownstone building.

Wondering if a small inflatable pool, @ 10 ft x 6 ft (which holds about 200 gallons of water) or something smaller holding @ 175 gallons, would be dangerous or if the deck would not support such weight.

I can calculate the weight of the water (8.35 lbs x 200 =1600 lbs), but I don't know the construction data re: the deck.

My girlfriend keeps saying it's too heavy, but what if we have 10 people who weigh 150 lbs?
It's the same thing. (I think).

Any help appreciated. Thanks

#### tpolk

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ok if i say yes and it collapses will you be mad at me for not telling you to grt it engineered which you know you should right?

bluejay1

#### bluejay1

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#### Grumpy

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Here is my take on it... 1) Was the roof designed for a Deck? 2) Was the deck designed for a roof? 3) Was the framing structure designed for the load necessary to carry the deck and the pool?

That pool will be alot of weight. I have seen on one projct at least where the ceiling was cracking from the weight of the small pool like you mentioned. The customer was concerned her ceiling was going to cave in, but more concerned that she wouldn't have a pool for the pool party she invited all her friends the coming week end. My advice to her was simple, as soon as the party is over remove this pool! Not only was the roof not designed for a deck, the deck was not designed for the roof, and I doubt that the roof structure was engineered to carry all the weight of the pool, or else the ceiling wouldn't be cracking. I recommended she consult and engineer, and gave her a price for a new roof properly constructed and a new deck on the roof again properly constructed and she never returned my phone calls after that.

Here is a good read: Chicago Roof Decks: What You Need to Know.

I was just bidding a project, a 2 flat in the city of Chicago. They wanted to pu a deck on their roof. I gave them a price for the roof and the number to an engineer. They hired me to replace the roof and called the engineer. I met witht he engineer, we opened an area of the roof and he came back with his report. The reinforcement necessary to carry the weight of the deck would have literally doubled the cost of the roofing job. The customer declined to have that done, but the good news is we discovered that in a past remodel that a load bearing wall had been removed. It caused the ceiling to sag down 3" so as part of the roofing project we will be supporting the ceiling joists. That has nothing to do with a roof deck though

My advice call an engineer, but it'll cost you a few grand and probably have to drop a ceiling or open up the roof to examine the framing. However I am not sure about those steel beams, are they supported on the outside walls? Pics may help, but only an engineer will be able to give you a stamp of approval.

#### Leah Frances

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What's the worst that could happen????

Before anyone jumps on me, I'm OBVIOUSLY joking. Listen to Grumpy, he knows what he's talking about.

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