humfrz swimming pool project - help
 

OK, fellow OT-ers, I am pondering a situation, that you construction/structural minded folks may be able to help me with.

Well, it’s that time of year to put up the pool for the granddaughters.

Since they are bigger, I got a bigger pool which is 10 feet in diameter and holds 1,000 gallons of water.

(to help you with the math ….1,000 gallons of water weighs about 8,380 pounds (plus (2) 50 lb. kids = 8,480 pounds.)

I usually put the kids pool (which was smaller) on the corner of our deck.
Now that the pool is bigger, thus heavier, should I still try to put it on the deck.. ??

The deck is about 30 years old, but in good condition.

Referring to the underside picture, the center of the pool would be about where that back vertical rod is hanging down.

The two posts that are shown are 4’ apart, 8’ tall, 4”x8” in diameter. They are set on concrete piers.

The cross member over the posts is 4”x10” ; the floor joists are 2”x8” on 16” centers.

The decking is made up of 2”x6”

First question is …. do you think I would need additional support to support the filled pool .. ??

If so, would 2 additional 4’x4” vertical posts, set on concrete pillars, topped by a 8’ 4”x4” placed this side of and parallel with that 4”x10” cross member be sufficient .. ??

If not, what would you suggest ... ??

TIA

humfrz

Personally, I wouldn't support 4+ tons on a wooden deck. This would be like driving a large U-Haul truck onto a wooden dock. Just too much risk of the deck collapsing IMO.

i would probably not do that. to give you an idea, the extra weight of our composite decking needed the joists to be 12 O.C.

you'd probably have to do a structural load take down equation to see if everything works. (it's beens years since i've done one)

Key words when talking 30 year old outside structures ^^^^^


I will throw in with the others and advise against.

It's not a stationary load either. "There will be sloshing!"
Random weight transfer and torsional loading on the stringers. Are the deck boards nailed or screwed down?

In my limited experience I think a couple extra posts would support the weight side it's spread out BUT the deck is 30 years old. Probably safer for them and your home owners insurance if you didn't put it on the deck. Consult a professional if you really want to make this happen

yeah i think cedar is supposed to be good for 25-30 years.

More support definitely if 30yrs. Especially if you want it to last another 30. I am thinking humidity will speed up the rotting and deterioration of the pool surrounding...also if it ever freezes there will be a tad extra weight. My uncle built a medium sized (14ft deep by 10ft approx radious pool) and it caved in once in winter, then once in summer. He resolved this by adding [rubber] cement below it. Then, added marble tile below. This added more weight and the pool over time has gone crooked.

I helped him install the tile but that's it so I don't have much experience in this. But, I would definitely reinforce things. Just in case...


P.s. his home was built in 1957. Pool was put in the 1960's. Rebuilt in 1984 and then 2011 with me. Oh and his house is on a hill.

Nailed down ...... that is one of the granddaughters spring time jobs ...... is to pound the nails back down.......takes them a while ........ :)


humfrz

How big was the last pool

Good point. I will consult with my son-in-law, who is in construction and builds houses. After all, these granddaughters, who will be using it, are his daughters ...... ;)


humfrz

The old pool was about 10' x 6' x 1.5' deep.


humfrz

So*roughly* half the size? I'd definitely talk to the son/inlaw/whatever. Do you have an alternative location for this thing? Did you save the receipt?