What's the best surface for your spa?

[d8]

The question arises often enough with customers, so I thought I'd ask all the tech/delivery guys/dealers here what they recommend.  

If this horse has been beaten to death, let me know and I'll delete the thread.

Here's my two cents:

Concrete pads are great for delivery. We can trailer up to the site, slide the spa onto casters and have it place in no time at all. The spa customer knows he has a good solid base under his tub. The downside is a lack of drainage for splash-over and cover dripping.

Flagstone, pavers, brick are pretty good for delivery and set up. The drainage thing can be an issue. I've seen a few that weren't that well laid out or leveled, but never one that was really unsuitable for a tub to sit on.

Decks are similar in ease of placement, provide more drainage than a pad, but require enough support for a full tub. I've set up a spa on two on some that I though were marginal. I advise the customer to add extra support in that case.

3/4 crush gravel in a braced 4x4 frame is what we usually recommend. The delivery and set up is slightly more difficult, but we've got some good techniques to set a spa in place without messing up the gravel. The downside to gravel is that sometimes the customor's pad is not really level, or the frame is not big enough and the base of the tub overlaps the 4x4s.

Pea gravel is not recommended because it has a tendency to shift over time and can leave the customer with level problems, or worse, a void under the spa.

We've done a couple on railroad ties, and one on bare ground. The ties work just fine, but the bare ground set up, I'm uncertain about. I wouldn't recommend it for any spa that didn't have a full ABS base.

[hottubdan]

Good info.  I concur.
 

[Vanguard]

I've had a spa on a pea gravel concrete patio and a broom finish patio.  I did put a ever so slight slope to the pads for drainage.  I've never had an issue with water under my tub.  I've been fine with both and both have held up.

[Tailhooker]

I was told today that by a dealer that he prefers and recommends concrete slab over the all other surfaces due to the weight of the spa.  With the spa going pretty close to the side of the house would the slab be a problem?

[Chad]

I was told today that by a dealer that he prefers and recommends concrete slab over the all other surfaces due to the weight of the spa.  With the spa going pretty close to the side of the house would the slab be a problem?

Not at all. Make sure the contractor "ties" in the slab to your existing foundation with 1/2'' rebar.

My spa sits on a slab and is only 3' from my house. I haven't had any problems whatsoever. Not even any hairline cracks. It's tied into my foundation with rebar and is 4'' thick. See pic below.

[BauerN]

3/4 crush gravel in a braced 4x4 frame is what we usually recommend. The delivery and set up is slightly more difficult, but we've got some good techniques to set a spa in place without messing up the gravel. The downside to gravel is that sometimes the customor's pad is not really level, or the frame is not big enough and the base of the tub overlaps the 4x4s.

Missed this one when it was new.

With a larger background in heavy construction and mining than spas, let me add a tidbit:

1)  Gravel pads are simple enough to level and fix for a customer (I love to go an extra mile if I can anyway).

2)  Gravel pads do not require a slope to facilitate drainage (as does a concrete pad).

3)  Contrary to some popular myth - a gravel pad (crushed gravel) is more foolproof than concrete.  It's much easier to screw up concrete and have it fail in the future. (Anyone here ever see a cracked driveway or patio without a spa?)  Properly laid gravel will be every bit as strong and long lasting as concrete (with the exception of the wooden frame - some of my customers have gone to composite materials with great results.

4)  Most importantly - I would stress that this is more of an aesthetic issue, dependant upon situation and individual.  

Any of the previously mentioned methods in this thread (except virgin earth - if someone needs more info on this ask or PM me), are going to be as good as the materials and workmanship.

If you d-i-y:  research first and don't cut corners.
If you hire out:  research first and hire a REPUTABLE contractor.

[Too Tense]

Bauern

Here's my dilemma. Wife wants me to order the spa now will take 3-4 weeks to get here. I just can't makeup my mind which direction to extent my deck for the best view and privacy from 2 of my neighbors. Also once my deck is completed I will have to use a crane to place spa on deck.

I have considered pouring a concrete pad for a temporary fix for now, but it's a little pricy being that it's temporary. Someone told me to place 6" of crushed limestone then I can rest the spa on it after packing it down.
You suggest crushed gravel. So which one is better to use gravel, or limestone and how deep do I need go, do I place anything underneath either one. I will frame with 6x6x10. I live in the midwest and yes it gets very cold here 4 months out of the year. It is very windy were my house is as well if that makes any difference on how I need to prep and install.

This will buy me time to do what I  need to best extend my deck the right way next spring. I want to enclose with screening and a roof 14'diameter to take advantage on the fantastic  view we have.

Any help will be greatly apprecated.

[Calypso]

Not at all. Make sure the contractor "ties" in the slab to your existing foundation with 1/2'' rebar.

My spa sits on a slab and is only 3' from my house. I haven't had any problems whatsoever. Not even any hairline cracks. It's tied into my foundation with rebar and is 4'' thick. See pic below.

Be very careful if you are tying into your existing foundation. If the previous contractor for the house did not provide adequate compaction or there is "soft" soils below your house foundations you could end up settling your house foundation and/or cracking the foundation at that location. The soft soil layer could be up to 10 feet below your house and this added surcharge may be enough to introduce long term settlement or "creep"

Your should pour the reinforced concrete pad independenly of your house foundation and ensure that this pad is on a suitable compacted granular sub base.

Concrete is the way to go!

From D8

Concrete pads are great for delivery. We can trailer up to the site, slide the spa onto casters and have it place in no time at all. The spa customer knows he has a good solid base under his tub. The downside is a lack of drainage for splash-over and cover dripping.

Splash over on the concrete is not an issue. Concrete is easy to clean and you will not get any debris into your hot tub, bugs and rodents will not get underneath so you do not need a plastic base, your tub will never settle, your can colour or imprint designs into the concrete, roots will not move your tub etc. I could add a few more. Concrete is the best option and will add less than $700 to your costs over and above a gravel pad. If you are spending $10,000 or more on a spa you want your pad to last for at least  10 years without any issues.

Just my 4 cents worth

[BauerN]

Bauern

Here's my dilemma. Wife wants me to order the spa now will take 3-4 weeks to get here. I just can't makeup my mind which direction to extent my deck for the best view and privacy from 2 of my neighbors. Also once my deck is completed I will have to use a crane to place spa on deck.

I have considered pouring a concrete pad for a temporary fix for now, but it's a little pricy being that it's temporary. Someone told me to place 6" of crushed limestone then I can rest the spa on it after packing it down.
You suggest crushed gravel. So which one is better to use gravel, or limestone and how deep do I need go, do I place anything underneath either one. I will frame with 6x6x10. I live in the midwest and yes it gets very cold here 4 months out of the year. It is very windy were my house is as well if that makes any difference on how I need to prep and install.

This will buy me time to do what I  need to best extend my deck the right way next spring. I want to enclose with screening and a roof 14'diameter to take advantage on the fantastic  view we have.

Any help will be greatly apprecated.

Being that this is a temporary set-up, I would use 4" of whichever one cost me less.  If this was a more permanent set-up I would recommend the crushed gravel (as limestone will break down faster).

4" will be sufficient, given that your topsoil doesn't have too high of a clay content (how soft does it get when it's wet - softer = more material needed).  You may want to vary the depth to make the spa sit more level.

With either material, I recommend a wooden frame around it, made from lumber no smaller than 4" x 4".

Especially in your case I recommend this type of pad.  Regardless of what anyone says, I have removed a lot of concrete (with a sledge or jackhammer - once with a Dozer), I have also removed enormous amounts of earth by hand over the years - the gravel/limestone is a LOT easier to remove.

As to the high winds:  I would strongly recommend adding cover tie-down straps.  The one's I've seen from Doc's site look very substantial, and he gets some of the best customer reviews I've seen.
On a side note, when it's close to zero degrees F, four people in and out of a spa - splash over does become an issue known as ice.

[Calypso]

On a side note, when it's close to zero degrees F, four people in and out of a spa - splash over does become an issue known as ice.

In the winter we can use rubber mats with holes in them on top of  the concrete in case there is a slipping hazard. It is sure nice to sweep the soil/leaves/grass off the concrete in the other months instead of getting it in the tub.

Without concrete you can have a heave issue because of the water in the ground freezing and thawing.

Just my other 2 cents worth

[edit]wow that 2 cents worth has made me a full member [/edit]

[BauerN]

Without concrete you can have a heave issue because of the water in the ground freezing and thawing.

If your material is properly prepared and chosen with gravel, this is rarely an issue.  This is why we want crushed, angular material, instead of round.

Let's not forget, enough frost heave will crack concrete.  And if it's enough to move 4" of gravel, with over a ton of spa and water on it - it is certainly enough to damage concrete.

Again, after working with concrete and gravel, the gravel is easier to repair.

[Calypso]

Let's not forget, enough frost heave will crack concrete.  And if it's enough to move 4" of gravel, with over a ton of spa and water on it - it is certainly enough to damage concrete.

A properly reinforced concrete pad with a properly prepared sub base will not crack. There may be minor hairline cracks, but nothing significent. The reason slabs would require removal is they were not installed correctly for the conditions they would be subjected to.

We will just have to agree to disagree as I believe concrete is the best option. Besides the wife likes the concrete so then concrete must be the best right?  

Permanent installation = concrete.
Temporary = whatever is the cheapest that works

[BauerN]

We will just have to agree to disagree as I believe concrete is the best option.

Sounds fair.  But, I do want to note that the proper gravel will match or exceed the subgrade used in a proper concrete setup - giving the same resistance to the formation of voids and humps.  

 

Besides the wife likes the concrete so then concrete must be the best right?  

The ultimate deciding factor!    We're SUV shopping at home and I'm gettin' killed!