Hot tub on existing deck?

[B.Spilner]

Has anyone around here done this?

How did you reinforce? Piles?

Any info would be greatly appreciated.

[C_Dave45]

Originally posted by sikid111
Has anyone around here done this?

How did you reinforce? Piles?

Any info would be greatly appreciated.





Put mine on my patio. Didn't do a thing to it.

http://i123.photobucket.com/albums/o312/CalgaryDave/House/pic-1152.jpg

http://i123.photobucket.com/albums/o312/CalgaryDave/House/IMG_3791.jpg

[B.Spilner]

What's supporting underneath, Dave?

[B.Spilner]

Here's my setup,

20x10 deck.

Lag bolted every 16"
3 6ft piles at the front
2x8 on 16" oc, doubled up under the hot tub (technically a 4x6)

I had it full yesterday, then found a leak in the light so I emptied it. Showed no signs of stress underneath but I'm still sketched out by it....total weight with water and 4 adults would be 4500lbs.



http://i46.photobucket.com/albums/f115/uknowsikid111/4EA78FA4-0894-43BB-B167-5187C1714AA4.jpg
http://i46.photobucket.com/albums/f115/uknowsikid111/AA51FC11-55D1-4D78-A9F7-D354E12A3307.jpg

[C_Dave45]

Nothing under mine. The garage is under it. It works out to under 100 lbs per Sq ft. Any proper deck should be able to support that and more. It's been there for 7 years. I've had as many as 6 ppl in it. No problems.

[CapnCrunch]

Originally posted by C_Dave45
Nothing under mine. The garage is under it. It works out to under 100 lbs per Sq ft. Any proper deck should be able to support that and more. It's been there for 7 years. I've had as many as 6 ppl in it. No problems.

Any proper deck is designed for a 40psf live load and a 10psf dead load. Anything over that and you're on your own.

[ExtraSlow]

The thing with a hot tub is that it's that much load PLUS whatever else is happening on your deck. If we get a heavy and wet snowfall, that'll accumulate a couple thousand pounds, PLUS the hot tub, which weights as much as a mid-sized SUV.

I can't help you with the engineering solution, but just some food for thought.

[sxtasy]

Wow I would never put a hot tub on a deck sitting on patio pavers on disturbed soil. Concrete piles below frost is the way to go.

[bspot]

As CapnCrunch said, a permitted deck in Calgary has to be designed to 40psf.

A hot tub base is about 36 sq ft, 4500 lbs, plus 1 ft of wet snow at 20psf, you're sitting at 145psf.

That is crazy.

[C_Dave45]

Originally posted by bspot
As CapnCrunch said, a permitted deck in Calgary has to be designed to 40psf.

A hot tub base is about 36 sq ft, 4500 lbs, plus 1 ft of wet snow at 20psf, you're sitting at 145psf.

That is crazy.

I better get my hot tub off of there right away!! :nut:

First of all, your numbers are a little skewed in my case.

My hot tub is 49 sq ft. With a filled weight of 3,340 lbs. Also, while a standard deck is "rated" at 40psf, that is a minimum standard for all areas of all decks, no matter what finished decking is used. A 15 foot span of 2x10's, covered with 2x4 planks, is going to have a much lower "psf" rating than a deck with a span of 8 feet, covered with 3/4" plywood. Also the force of something placed in the middle of a large span will be much higher than the same weight siting close to the edge of the supporting walls.

My "70 psf" tub, sits on a span of 2x10's of 9 feet. Also it sits right on the edge of all three bearing walls.

Does that mean that my completely filled fridge, weighing roughly 400 lbs sitting on 6 sq ft is in danger?
Or when my 300 lb friend stands on one foot, exerting roughly 1500 psf, might fall through the floor??

As you can see...a "psf rating" can vary greatly. Add to that, the safety factor built into "codes". After 10 years, and multiple "parties" with as many as 40 people on my entire patio, I don't think my hot tub is going anywhere.

OP might want to consider his own situation completely different though.

[bspot]

I'm saying unless I had access to the load tables myself, I'd get it engineered.

[Cos]

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[Tik-Tok]

Originally posted by Cos
How much does the hot tub crane cost to do dave? Do they charge you extra to swing it that way?

*insert hot tub and swinging joke here*

[C_Dave45]

Originally posted by Cos
How much does the hot tub crane cost to do dave? Do they charge you extra to swing it that way?

Bear in mind this was 10 years ago; I used H&H Crane services and they charged $110/hour for that particular crane. It was a long way from the road too. About 40 feet. Total charge was 1 1/2 hours for a total of $173.