Pool construction simultaneously with house construction - Your assessment

We have received the first of three offers today. It is the PP version. We had two offers calculated: a small version measuring 6.7 x 3.3 x 1.5 m and a large version measuring 9 x 3.7 x 1.5 m. Both are intentional, a "medium version" would then lie in between. Some items are logically the same, price differences are mainly in the pool, bench, spotlight, and underfloor roller shutter.

The offer includes the basin, double-walled sheets behind it (for stability and insulation), a non-continuous staircase on one end, and a bench on the other end, PVC underfloor roller shutter, technology package (filter container, pump, measuring and control unit, UV-C disinfectant), 4 inlet nozzles, bypass, 1 or 2 LED underwater spotlights, piping, delivery up to the sidewalk edge.

Missing are: heat exchanger or heat pump, electrical installation, crane, foundation, and concrete.

In total, the small version comes to 43,870 euros including VAT and the large one to 50,417 euros.

My questions:
1. What do you say about the price/performance ratio?
2. How important are the double-walled sheets behind the PP walls? These cost 4,000 or 4,900 euros.
3. Our contact person could not say for sure whether a heat pump is necessary or if a heat exchanger is sufficient. That would depend on the final pool size. I have no idea about this. Can you enlighten me? What price range are a heat exchanger/heat pump in? Photovoltaics will be installed on the roof.
4. In what price range do you estimate a) excavation and construction of the concrete foundation b) crane and c) backfilling with concrete, if the pool is built simultaneously with the house?

1. Without more detailed information about the technology, it is not really possible to assess. I would not choose a PVC roller blind. Only polycarbonate, preferably in a solar version. The price is probably not totally unrealistic.
2. Important because of PP. Requires stability and insulation.
3. How much heating power you need I already mentioned. At least half the pool volume in heating power. You certainly don’t have that “spare,” especially not if the house is heated by heat pump. Whether heat pump or via heat exchanger on the primary heating system has nothing to do with the pool size. How big is the photovoltaic system. I think you underestimate the required heating power and energy. We are talking about 20kW heating power or more. The fact that the contact person has no knowledge regarding heating would make me very suspicious. (Or he would be immediately disqualified). Heat pump for this size is about €7,500 plus installation.
4. Depends on the ground, whether it has to be disposed of or not... Costs for installation of electricity, water, wastewater, control also have to be added.

We had our second consultation today and the first one with a GFK pool builder. The conclusion upfront: It was much more detailed, went significantly deeper, and was therefore a very big difference from the first consultation. He showed us the alternative, gave a recommendation, and then accepted our decision. He was either a very good salesperson or the vibe just fit. Probably a mix of both.

Here are the key facts:
- GFK Riviera pool Ancona D-Line in 6.5 x 3.2 x 1.5m
- Full inverter heat pump with paddle switch (?), outdoor unit about 70 x 70 x 120cm, suction from three sides
- Fully automatic measuring and dosing technology with multilayer filter grain using AFM
- Manual dirt filter cleaning (?)
- PP solar underfloor roller shutter
- Waiver of the approx. €6000 countercurrent system (although I really enjoyed the swimming pool during my sports studies, but one has to pick their poison)

Super practical was that he had installed exactly the same pool with PP solar underfloor roller shutter in our preferred roller shutter and pool color privately. He invited us to view it after the conversation, so we are very clear about the color choice of the pool and the PP roller shutter and the pool size.

My new questions:
1. He wanted to know from us what our preferred water temperature is. We said 26°C. Is that a sensible value for an "all-in-one" pool?
2. Suggested option: save on the heat pump and instead install a larger heater. What do you think about that?
3. Does the KFW funding not also depend on that?
4. He gave us extensive information about the topic of quartz sand filter media or AFM. What do you think about that?

As a supplement:
Our photovoltaic system is supposed to cover the entire roof. We are unsure about the storage system and are currently leaning towards foregoing it.

Ricky, even if this is more of a dialogue between the two of us here, I am very grateful for your input and at the same time look forward to further comments from other users.

- 26°C is for swimming. For children and paddling, it should be around 29°C. It also depends on the outside temperature.
- What kind of heating have you planned? How far is the pool from the heating system?
- AFM has a slightly better filtration performance than sand. It may last one to two years longer. However, this depends on water care and regular backwashing. It might make a difference of about 100€.

What kind of filter (diameter, amount of sand...) and pump does he offer?
Definitely install an automatic backwash (Besgo)? Otherwise, you will have to manually operate the multiport valve and pump on/off weekly.

My new question: 1. He wanted to know from us what our preferred water temperature is. Here we mentioned 26°C. Is that a reasonable value for an "egg-laying-wool-milk-sow" tank? 2. Suggested option: save the heat pump and instead install a larger heater. What do you think about that? 3. Doesn't the KfW funding also depend on that? 4. He gave us a long briefing on the topic of quartz sand filter media or AFM. What do you think about that?

Hello, if it's still possible, I would size the heat pump of the house so that it can also heat the pool. Provided the pool is not located too far from the house. In that case, I would also try to install the pool technology in the house's basement (usually 2 m² are sufficient for that). I would recommend AFM. It is somewhat more expensive, but it needs to be replaced much less frequently. The pool heater should be sized so that you can maintain the water temperature at at least 28°.

- 26°C is for swimming. For children and splashing around it should be about 29°C. It also depends on the outside temperature
- What kind of heating have you planned? How far is the pool from the heating?
- AFM has a slightly better filtering performance than sand. Might last one or two years longer. But that depends on water maintenance and regular backwashing. Maybe makes a difference of 100€.

What kind of filter (diameter, amount of sand...) and pump does he offer?
Definitely install automatic backwashing (Besgo)? Otherwise, you have to deal with the multiport valve weekly, pump on/off/on/off.

We have planned an air-water heat pump. The technical room is in the basement in the south/southwest and the pool is above it. That means the distance is quite short because there are no rooms in between, only the terrace. There would also be a convenient spot for the pool heat pump, but without an outdoor unit I would of course prefer that for aesthetic reasons.

I can’t name the exact filter yet. I will provide that as soon as I have the offer.

Regarding the automatic backwash, I am really unsure. He said the automatic washes way too often and it can be done quite quickly and easily manually. The hardest part is "remembering to do it." He also said that officially you have to backwash every week, but it can also last up to three weeks.

Hello,
if it’s still possible, I would dimension the heat pump of the house so that it can also heat the pool. Provided that the pool is not too far from the house. In that case, I would also try to accommodate the pool technology in the basement of the house (normally 2 m² is enough for that). I would recommend AFM. It’s a bit more expensive but has to be replaced much less frequently.
The pool heating should be dimensioned so that you can keep the water temperature at least 28°.

Exactly! Pool technology should go in the basement. He also recommended the larger heating instead of a separate heat pump but at the same time expressed concern that it might no longer qualify for the KfW subsidy due to the poor energy consultation. Do you have a gut feeling about this?

Thanks also for the tips about the water temperature. The pool should definitely be for splashing around. I will still add the 28/29°C you mentioned!