Wood vs metal frame

[HotTubMan]

I object to the house analogy. Yes there are houses still standing that do not have metal or pressure treated frames. Are these houses holding hundred of gallons of water? Do these houses have leaks that expose the framing to the moisture? No that goes down to the concrete foundation.

Dont get me wrong, I was the first in the thread to say it isn't that big a deal. To compare a tub to a house is a weak comparison. Why dont we compare the tubs to cars? They use metal frames that dont last nearly as long as tub frames or house frames. Does that mean that wood is in fact superior or does it mean that the cars metal frame is exposed to different environmental factors?

HTMan

[TALKCalgary.com]

Boy that sounds familiar.  You full foamers make a living out of saying full foam is a  better way to go than thermo(pain).

Guess thermopane is a gimmick too.

New definition of gimmick:

Any implementation used on a spa that the "full foam junta" does not like because they don't use it.


I'm not a rocket scientist or a metalurgist but if you were to poll people walking down the street, not knowing a thing about spas, and ask them if they had a choice of a metal or wood frame I think 99% of those polled would choose metal.   The reason Watkins, et al, do not use metal yet is because production costs would go up and they know they already overcharge the public for the product they make.   Thus, they would have to raise the price even more, thus hurting their precious sales.  

Just get over it.  Thermopane and metal frames are here and aren't going away anytime soon.  At least until someone invents the thermo-gravitational force field that will make up the spa of the future.  Just think of it, no frame, no shell, no foam, just a blob of water suspended in air to soak in.  Privacy issues would have to be addressed of course.  

This has to be two of the most sensible and unbiased postings I have read for months :-)

Well said Rick & Spahappy

[spahappy]

This has to be two of the most sensible and unbiased postings I have read for months :-)

Well said Rick & Spahappy

Thanks, it's good to be back!!

Spahappy

[Kelley]

Hi All,
I'm the husband that Kelley spoke of in the original post.
My concern over wood frames comes from crawling under my house and replacing 2x6 joists under the bathroom. Obviously the shower, sink and tub are not supposed to leak, but they did - and will eventually leak.

I'm nervous in this situation; several hundred gallons of water running through hoses secured with crappy clamps (look at the hose clamps on your car's radiator hoses for an example of a real hose clamp), and the possibility of water flowing out of the tub when it is accidentally overfilled, all of this happening within inches of wood, ready to absorb water into that kiln dried goodness....

Pressure treated wood works, metal frames are just a long term insurance policy. Not stronger, nor will they last longer than the expected life span of a spa. But if an accident happens I know that steel can handle a single, unseen, water exposure better than wood.

I don't own a spa. The frame of the spa I buy might actually be made of wood - but I'll regularly check underneath for any moisture.
The frame is not a deal breaker but it might swing me one way or the other.

Great advice here - although I can smell the salesmen a mile away

[ebirrane]

This has to be two of the most sensible and unbiased postings I have read for months :-)

Well said Rick & Spahappy

[ebirrane]

Boy that sounds familiar.  You full foamers make a living out of saying full foam is a  better way to go than thermo(pain).

Guess thermopane is a gimmick too.

New definition of gimmick:

Any implementation used on a spa that the "full foam junta" does not like because they don't use it.

Rick, did a full foam hot tub harrass you and take your lunch money when you were in high school? You've got some serious full foam bigotry in you.  

As for the wood versus metal I wouldn't base my argument on "any Joe Schmoe" walking on the street to have any kind of informed opinion unless they have researched it.  Presumably, people on these boards *have* researched it.  Some here, obviously, haven't.

Pressure treated wood will stand up as well if not better than metal.  Why do I say better? To keep costs and weight down some use inferior metal with inferior coatings to keep cost and weight down.  When done that way it *is* a gimmik. Improper use of wood rots and threatens structural integrity.  Improper use of metal rusts and threatens structural integrity.

And yes, untreated wood under a spa skirt can be a problem. Pressure treated will not be. A quality manufacturer will ensure that it is not an issue, either from use of wood or from use of metal.  

But when someone is in the market for a tub and they just post generic questions, you don't know if they are looking at a reputable brand or not and so you do have to address the wool that can be pulled over peoples eyes.

-Ed

[ebirrane]

I object to the house analogy. Yes there are houses still standing that do not have metal or pressure treated frames. Are these houses holding hundred of gallons of water? Do these houses have leaks that expose the framing to the moisture? No that goes down to the concrete foundation.

The wood or metal in a hot tub is not exposed to water unless there is a leak in the hot tub just like the wood in your house is not exposed to water unless there is a leak in your tub, pipes in the walls burst, appliances leak, toilets overflow and flood, you live in Florida or New Orleans right now,  etc..

The house analogy wasn't to try and justify use of non-pressure treated wood in a hot tub. Your hot tub, most likely is outside and a 1/2" piece of plastic skirting doesn't change that. It will most likely, over the course of its life, experience the outside environment.

A better analogy might be a deck using pressure treated wood which gets *much* more exposure to the environment that the wood inside a hot tub skirt.  

Just a quick aside, off topic, Alot of people were using those metal "2x4"s for construction. They are always straight, lighter, and cheaper.  In a fire a 2x4 will burn for a good while.  In a fire, once the metal hits its melting point *poof* goodbye metal stud.  Something to think about if you are paranoid.

-Ed

Just had to edit this in: You need pressure treated wood if it is pine that makes up your tub frame.  If you use woods like cedar, rosewood, Douglas Fir (I think..)  they do *not* require treatments.

[Brewman]

Far be it for me to toss gas on the fire, but are those metal studs you refer to used as structural support walls, or just for divider walls?  In our office here, they use the metal studs to put up divider walls.  But I haven't seen any houses built with steel support walls.

As far as price goes, I looked into the steel thing for my latest basement construction project, and while the studs themselves were cheaper than a 2 X 4 stud, by the time you get all the other pieces you need, top and bottom runners, gromet inserts for protectting the electric lines, the prices were too close to be of any issue.  So I went wood.  One thing nice about the steel studs may be that they are all the same.  No having to sort thru the wood pile to find acceptably straight boards.  


Gimick count: (aka: arguments that are un-winnable)

Full foam vs thermopane
Circ Pump vs not.
wood frame vs steel
ford vs chevy
my dad can beat up your dad

Brewman

[BobRex]

One of the things to keep in mind with pressure treated is that as it dries out it tends to twist and warp.  Now I don't know if that's an issue with the relatively small pieces used in a tub frame, but I would be concerned if the only connectors holding the frame together were staples.  Does anybody use screws to build frames?

Along the same lines, if the frame were made of douglas fir, then that frame should be treated with some sort of preservative.  Untreated doug fir will rot.

One advantage of metal frames is if you need to bore through the stud to run plumbing or wiring, the metal stud will retain a greater portion of its strength than a wood stud.

Honestly though, I doubt there is any real difference between the two materials in the context of a tub.  In home construction, metal studs are generally used for fire retardation or where mold may be an issue (wet basement).  In the "sealed" environment of a spa (assuming no leaks or leaks are properly attended to) the mold issue should be minimized.  An id case of a fire, well, there are other issues to be dealt with  .

[HotTubMan]

But Brewman! My dad can beat up your dad!

 

[tazman]

I agree that pressure treated will be an issue! It's very hard to keep 2x8 joist on a deck from warping, have you ever gone through a pile of them at the lumber yard trying to find a straight one? Now, think about it being a pressure treated 4x4 or 2x2 that’s even worse. I agree with rocket on the Cedar frame probably being the best, every signpost, mailbox post or fence post we put in the ground is cedar. It stays straight and doesn't rot.

Rick, I don't think TP is a gimmick but I also personally prefer FF. I would be interested in your experience with FF that left you so passionate against it! Did you have a bad experience or just a very good salesman for FF!

[empolgation]

I agree that pressure treated will be an issue! It's very hard to keep 2x8 joist on a deck from warping, have you ever gone through a pile of them at the lumber yard trying to find a straight one? Now, think about it being a pressure treated 4x4 or 2x2 that’s even worse.

I'm not sure what the issue will be, but it certainly can be hard to keep a 2x8 joist straight and lumber quaility in a retail yard is terrible.

The bigger the span of lumber the greater the chance of warping, bowing, crowning etc...  if you get the chance, take a look at 4x4 and 2x2 pressure treated wood at lengths 8 feet and under and compare their quality to long lengths of 2x8. Compare pressure treated lumber that is incised with lumber that is not incised. Also note what grade all the lumber is; there's a big difference between select structural and No. 2.

[ebirrane]

I agree that pressure treated will be an issue!

Who are you agreeing with, and what's the issue? BobRex wasn't sure it is an issue at smaller lengths. The 2x8x12s I bought for my deck were straight.

Again, go back to the house example. If wood twisted and warped so much our decks would resemble a mobius strip by now!  Our house walls would be inside out.  Every wooden fence in the world would rot out, fall off, and twist itself into pieces.

Please, stop the insanity!

-Ed

[Tman122]

Any one who says metal will last longer than wood is dead wrong. I have gone through 2 babacue grills on the same deck! Water is worse on metal than treated wood. Now if the metal was an inch thick? But thin galvinized will rot faster than good treated wood. Now lets talk rivets ohhh wait don't get me started. Both are good and should not be used as a superiority trait over the other. Comfort in the dealer and the tub on your back side. Oh............ metal is noisy, rivets vibrate loose...ooops sorry I wasn't going to do that!

[BobRex]

Ummm, Tman, I've got a Weber grill that's 7 years old, sits outside, albeit under a roof (can we agree that that's similar to the environment that a tub frame is exposed to?), no cover, and has no rust!  I've got a galvanized watering can that always has water in it.   Guess what... no rust after 5 years.  I can remember having galvanized trash cans that took 10 years to show serious signs of rust.

Now tell me that a tub frame will be in a similar environment (constant contact with water, exposed to the elements, victim to all sorts of "trashy" liquids) and I might agree that galvy might be a bad idea for a frame.  But since it's not, I won't.