Hot Tub Forum

Original => Hot Tub Forum => Topic started by: dazedandconfused on May 21, 2004, 10:07:41 pm

Title: Spa Bottoms
Post by: dazedandconfused on May 21, 2004, 10:07:41 pm
Are there any spa manufacturers that use a solid plastic cover on the bottom?  What do Sundance and HS use?

I hate to see my future spa resting in water over the years.  I can't imagine what it would do to all the wood inside.
Title: Re: Spa Bottoms
Post by: Mendocino101 on May 21, 2004, 10:12:42 pm
Marquis spas do....They have what they call there durabase foundation...I believe that Sundance also has something simluar....
Title: Re: Spa Bottoms
Post by: dazedandconfused on May 21, 2004, 10:15:44 pm
Has anyone had trouble with moisture coming thru the bottom of their spas and decaying the wood structure?  ANything I could do to prevent this from happening?
Title: Re: Spa Bottoms
Post by: rick on May 21, 2004, 11:46:58 pm
My Calspa experienced what you just described.  
A neglected leak that caused the whole foundation to rot out.  (when they came to haul it out, it would not move in one piece, it just started falling apart and they ended up sawing it into pieces to get it out of there.)When I first noticed the leak I called around and nobody wanted to touch it with a 10 foot pole, it being a full foam job.  I then opened up the paneling and saw first hand what full foam looks like.  It looks like somebody just started cramming assorted chunks of foam into this guy. I now pity anybody who is tasked with digging out such a leak.  
Now my Calspa was pretty old too.  It was probably close to 15 years old,  it came with the house when I bought it.  
So when the leak got so bad, (close to 1 foot loss of water per day), I started shopping and researching.  
No, I claim to be no expert in spa design and while what I learned in my 3 weeks of searching is nowhere close to becoming an expert in the field, I did learn about the thermopane design and when I walked into the Coleman dealer I was doubly impressed with its all metal foundation.  No wood whatsoever.   This spa is also now much lighter than the "regular" spas,(unfilled of course)  meaning easier to move in case I decide to change residences one day.  I didn't spend over $8000 on a toy that I plan to leave with this house if I ever sell it.  My toy is going with me to my new house, and I hope that it outlasts the 15 years that the CalSpa gave me.  
To me, it just seems like common sense that the spa industry will move to this kind of design but you say the word thermopane on boards like this and the full foam guys just start bashing and making all kinds of claims of inherent problems with this design.  I just don't know.  Maybe they're all right.  Maybe the day my warranty runs out this guy is going to start leaking like a sieve and running up my electric bill.  Only time will tell, but I just have a better feeling all around about how my spa's made.  
Title: Re: Spa Bottoms
Post by: Steve on May 22, 2004, 12:13:27 am
Great question Dazed.

Personally, I find floors on the bottom of a hot tub somewhat redundant.

From a moisture perspective, if the materials used are pressure treated, this will never be an issue. Anyone built a deck recently?

The other reason would be to prevent rodents and such from entering the cavity. If this same 2X4 structure sealed the entire bottom edge, they would either need to come up through the cement foundation or eat through the pressure treated wood. Neither scenario is realistic.

The question should be, what materials are being used for the structure and will it be susceptible to rot? Does plastic break down over time? Does steel rust?

As for Rick, comparing a 15 year old design to concluding what type of insulation method is best currently, isn't really relative. This isn't a comparison on thermal "pain"  ;)  and it really has nothing to do with the question. I'm sure your tub will give you many years of pleasure but the decision of purchasing a fully insulated spa or not, equates to about 5% of the significant factors in this purchase.

Steve
Title: Re: Spa Bottoms
Post by: rick on May 22, 2004, 12:19:03 am
See what I mean?
And I disagree with the 5% figure.  I'd add a 0 to the end of that 5.  But that's just my opinion as a former "full of it"  foam owner.  :)
See, I can play nice.  
Title: Re: Spa Bottoms
Post by: Steve on May 22, 2004, 12:36:30 am
No problem Rick... You are allowed to disagree. :)

Steve
Title: Re: Spa Bottoms
Post by: Electro on May 22, 2004, 12:39:18 am
dazedand confused,               ::)        :)

I think this is an interesting topic and hope there are folks who can shed some light on what the big 6 hot tub makers actually have on the bottom.  I don't think any sales literature addresses this.

What about it, dealers?

Electro
Title: Re: Spa Bottoms
Post by: Chas on May 22, 2004, 02:08:38 am
The bottom of a HotSpring spa is sealed with a layer of 60# density closed cell polyurethane foam.

It is almost as hard as the shell material - but thinner. It works well - my delivery guys can't even ram the tips of the forks on my forklift through the stuff, and believe me - they try.
Title: Re: Spa Bottoms
Post by: doodoo on May 22, 2004, 08:28:11 am
Dazed and condused. We looked at an Arctic Spa that had a full plastic bottom. Kinda like a full shell about 1/4'' thick and coming up about 4-6'' on the sides producing a mini casing that the tub sits in. I think?

In looking at the other method which is described by Steve is IMO more effective as it seals the base from moisture penetration.
Title: Re: Spa Bottoms
Post by: dazedandconfused on May 22, 2004, 08:34:26 am
Thanks.

Any Sundance dealers or owners out there?  What is on a bottom of a Sundance?
Title: Re: Spa Bottoms
Post by: tony on May 22, 2004, 08:36:41 am
I am not a dealer, but Sundance uses a hard plastic sheet attached to the bottom, different than the Jacuzzi Premium ABS pan.
Title: Re: Spa Bottoms
Post by: Tubber on May 24, 2004, 07:47:21 am
Sundance has a full plastic hard sheeting underneath.  With the front panels removed you can clearly see it.

"The bottom of a HotSpring spa is sealed with a layer of 60# density closed cell polyurethane foam. It is almost as hard as the shell material - but thinner. It works well - my delivery guys can't even ram the tips of the forks on my forklift through the stuff, and believe me - they try. "

This would make servicing the tub a little harder
Title: Re: Spa Bottoms
Post by: dazedandconfused on May 24, 2004, 10:19:09 am
So there is a definate plastic 'tray' under a Sundance?  

I looked inside the HS's and Sundances and was surprised to see 2x4's for support!  Wood!  How long will that last?

I am surprised!
Title: Re: Spa Bottoms
Post by: Brewman on May 24, 2004, 11:03:07 am
Pressure treated pine will last a good long time.
So will naturally rot resistant woods like cedar and redwood.  
I really have not observed what type of plastic sheeting is underneath our Optima, or how thick it is.  But when I remove the service panel to access the drain, it seems good and dry inside.  
Unless the plumbing springs an internal leak, I'd suspect it would stay dry.
Brewman
Title: Re: Spa Bottoms
Post by: dazedandconfused on May 24, 2004, 12:56:30 pm
Can anyone post a picture of the bottom of a Sundance or HS?

THanks
Title: Re: Spa Bottoms
Post by: Spatech_tuo on May 24, 2004, 04:37:31 pm
Unless you're living in the swamps of Louisiana, I think maybe you're worrying a bit too much here and even in wet environments like Fla and La a well designed tub shouldn’t have much of an issue. There are multiple ways used to make a spa bottom but I doubt it rarely comes into play unless someone is using untreated lumber.
Title: Re: Spa Bottoms
Post by: poopsy on May 24, 2004, 04:50:55 pm
i am intrigued by the spa bottoms.I do like the rewards bottom dish like thing..its a good concept.....

i also like that coleman uses steel reinforcement instead of wood,,....seems like a good gimic although wood may retain heat longer then steel.....but strength wise steel is better.......

Title: Re: Spa Bottoms
Post by: Brewman on May 24, 2004, 06:15:29 pm
I don't think the thermal properties of either material really matter.  And wood is not automatically inferior to steel, it all depends on the engineering.  
I'd let other criteria steer my decision.  Unless you insist on steel framing, which narrows your options considerably.  
Brewman
Title: Re: Spa Bottoms
Post by: Tubber on May 24, 2004, 08:31:52 pm
Sundance uses treated Redwood or cedar. isolated from the insulation by a liner.
Title: Re: Spa Bottoms
Post by: superted on May 28, 2004, 03:39:20 pm
Have you ever moved an old tub (ten years plus) they all have rot on the wooden structure. The bottom sits on the ground where moisture begins to eat at the wooden structure. Even redwood or pressure treated pine will eventually rot, but is sped up by leaks in the spa. I have moved hundreds of spas and when tipping them on edge a lot of them are rotted throughout. Even the pressure treated ones. The thicker the frame the longer it last's. 2x4 out lasts 2x2 and steel outlasts 2x4.