We’re putting in a pool, and need to decide whether to build in a spa. What’s it cost to heat one of those suckers, the kind of size that fits say 6 people, the typical built-in ground kind?
We have a jacuzzi tub in our bathroom already, but rarely use it.
Where do you live? That will make a huge difference in heating costs.
I ended up removing mine because: 1) as an athlete soaking in hot water is the opposite thing you usually need after a workout, 2) when it was 0 degrees outside we would cringe every time we heard the electric heater kick on. Overall in the winter is was really fun to sit out there in the evening with the snow falling but during the summer after it has been 90 degrees the last thing I wanted to do was sit in a hot tub when it finally cooled off at night. We just didn’t use it enough.
FWIW, we’ve never used jets in the bath either, but the type of use we get out of the outdoor spa is completely different. We (the adults) prob use the spa more than than the pool (smallish pool not suited for lap swimming). Like JT, we use the spa mostly in the winter months. Nothing better than firing it up on a nice cold evening and climbing in with an adult beverage and a good cigar. We built ours so we have an unobstucted view of the tv and have outdoor speakers, so we can watch tv, a ball game, or a movie from the spa if we want. New Years Eve is always in the spa with a bottle of bubbly.
Our heater is propane fired. Cost is about 5 gallons of propane per use to heat it up when it’s cold and an hour or so of soaking on average. Propane is running us about $4/gallon right now so figure $20 or so for an evening in the tub. It’s not an every night thing…maybe 4 or 5 times a month in colder weather, less when it’s warm. As you’d expect, in warmer weather the cost drops quite a bit…maybe as much as 30%.
We also have a control unit for the heater/pump inside as well as at the spa itself…something that I highly recommend.
Hope that helps.
You could look into heating using solar panels. I think it saves a lot… down the road.
When we were looking for a house, the owner told us that the solar panels really helped with the heating costs for the pool.
I have a 6 person above ground hot tub, about $50-60 per month to run in Southern California.
I’ll come visit if you do. 
Sitting in the hot tub with a glass of wine after a long bike at Xantusia is one of life’s great pleasures.
clm
When we added a garage to the side of our house, we built a sunroom behind it to house the hot tub. It has big glass sliding doors to walk out to the pool and since it faces south, gets a lot of warming on winter days. The only problem is we never use it in summer.
I know that it seems like a great idea and all, and you might be able to afford it, but I think you really need to consider the environmental impact another hot tub in this world would have. What gives you the right to flaunt your wealth and good fortune like this?