We are building an in ground pool and spa in Iowa and need advice on the system design and plumbing with some special considerations due to the northern and extreme winter climate. I have a good foundation of knowledge because of TFP and my previous home’s in-ground pool. We are coming from the southwest so there are things I need to learn about prior to beginning this endeavor. I have had plenty of experiences in the past where I knew more than a contractor did and want to have a basic idea of what our needs and considerations should be prior to hearing advice from our PB.
We would like the ability to keep the spa open during at least some of the winter. No plan for a spa spillover due to the need to isolate the two bodies of water and keep the pool winterized and closed during winter. Our home builder thinks we need two completely separate systems but we have not spoken to a pool builder yet while I learn about this more in depth.
Our ideas and questions are listed:
We would like the ability to keep the spa open during at least some of the winter. No plan for a spa spillover due to the need to isolate the two bodies of water and keep the pool winterized and closed during winter. Our home builder thinks we need two completely separate systems but we have not spoken to a pool builder yet while I learn about this more in depth.
Our ideas and questions are listed:
- The pool will have an autocover and planning to use a thick custom foam cover for the hot tub.
- Looking to build perhaps a ~18’ x 36’ rectangular pool (so it can be easily covered), with tanning shelf, a spa large enough for 8 people or so, prefer look and customizability of gunite. Possible small pool water feature, such as a weir.
- Considering a vanishing edge on the pool due to looks and performance for skimming but I do have some concerns for longevity and durability in this climate and this will undoubtedly require close attention to construction and reinforcement if we go this route, from what I’ve read.
- SWG for sanitization of both bodies of water with acid injector, particularly important for the spa - I had a previous SWG drop-in on a stand-alone spa and the pH was always high, there never was enough time or testing to keep pH in check.
- Natural gas water heater, possible future solar supplement, also toying with the idea of smaller natural gas heater for spa and a heat pump for pool if going two separate systems route since the pool will not be heated during very cold weather.
I plan to have interior location space allocated for the pool equipment to improve the longevity out of the elements.- Can a pool heat pump be located inside of a warm interior room (if large enough) and draw heat in that way, with a small cooling effect as a by-product? (I think the answer is no)
- Automation system with acid injection (Pentair?)
- What pool automation system and model is recommended? I did liked my Pentair pump and SWG at my old home. Pentair has so many models of automation systems and components that I don’t know where to start.
- I am also a very handy DIY and installed my SWG and a pool heater with some help from my dad at my old home. I’m not opposed to doing some stuff myself to save money, especially for implementation of automation which I’m guessing gets expensive quickly.
- We may need to have a home generator to run pool (spa) equipment in the event of an outage during the coldest part of winter when not winterized. At minimum, we will probably have the wiring for this in place at the time of build.
- How should this pool/spa combo with the need to isolate the winterized pool be plumbed?
- Do we need a completely separate, duplicate system? Is there a way we can plumb the system using 2 pumps and sharing one heater, one SWG, one acid injector, etc…? Is there any scenario where some/a few components can be shared? Perhaps only automation controllers can be shared?
- The idea of having the ability to mix some of the pool water into the spa when the pool is not winterized to assist with chemistry and cleanliness is attractive, but perhaps this is not needed? I’m coming from a home with above ground spa and chemistry was not easy, draining and refilling required several times per year with very light use (it would be nice to avoid that). Perhaps I’m worrying about it unnecessarily if we have an acid doser and SWG on the spa with better filtration than what is found in stand-alone spas. Recommendations?
- If we were to do a shared plumbing system, I would want the automation system to be able to automatically switch between which body of water is being filtered and heated automatically so I don’t have to worry about the spa getting out of check.
- Does anyone have experience or recommendations for ground insulation around the walls and floor of the spa? I’ve read the frost line can be as deep as 4 feet here so anything we can do to lessen heat loss to the ground and improve efficiency will be good.
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