Note · Lets
Designing a sauna and plunge circuit for a holiday let, from check-in to changeover
A circuit in a holiday villa has a different job from one in a private home: it is used by strangers, for a week, in whatever state they find it. This note follows the guest from arrival to departure and the cleaner on Saturday morning.
Sections on this page
- The guest's week, in five scenes
- Three layouts that suit a let
- The control panel problem
- What goes in the listing, and what does not
- Registration, licences and the rules that are changing
- Size the cabin for the group, not the beds
- The card at the pool, in sixty words
- Quiet hours for the compressor
- Opening, closing and winter
- Insurance, safety and the neighbours
- A word to the cleaner, and to the property manager
- Cost of ownership, line by line
Short version: a holiday-let circuit is a small set of surfaces that wipe, covers that lift, two pools or a pool and a cabin that serve different seasons, and one laminated card. Everything else follows from those four things.
The guest's week, in five scenes
- Arrival, afternoon. The first impression is the terrace. The pool covers are folded or stacked, the robes are on the bench and a card explains in four lines how to use what is there.
- First evening. The cabin has been on a timer for an hour. Guests sit in the glass-fronted cabin, then cool off in the pool.
- Mid-week. Guests use the pair when it suits them and cover it when they leave. The routine is on the card.
- Last night. The cabin is used for the last time and switched off.
- Departure. The cleaner arrives in the morning.
Three layouts that suit a let
- A hot-and-cold pair and a glass sauna: the full circuit, for villas that let in all four seasons. See hot-and-cold circuits.
- A glass sauna and a free-standing ice bath: the lighter version, for flats and townhouses.
- A cold plunge pool alone: the cheapest addition to a villa that already has a swimming pool and lets in summer.
The control panel problem
Assume every button will be pressed; the circuit has to survive that. A single on-off at the cabin with a visible state, a heater timer that the owner sets, a chiller that the guests cannot reach and a card that says what the display should read. Ask for a heater with a timer and an over-temperature cut-out; ask where they sit.
What goes in the listing, and what does not
Say what is there: a glass-front sauna for four, a cold plunge pool at about 4 °C, a warm pool at 38 °C, the seasons it suits. Do not say what it does to guests. Health claims in a listing are the owner's risk and ours to avoid. Photograph the terrace at dusk with the cabin lit.
Registration, licences and the rules that are changing
Regulation (EU) 2024/1028 on short-term accommodation rental data applies from 20 May 2026. It does not itself create a registration duty, but where a registration procedure exists the host must give the platform the number, and the platform must make sure the listing shows it clearly and check it at random (EUR-Lex, OJ of 29 April 2024, Articles 4, 6 and 7). Hotels and campsites are outside it.
In Spain, a national registration number was created by Royal Decree 1312/2024 and was due to apply from 1 July 2025. The Supreme Court annulled the registry procedure in its ruling of 19 May 2026, published in the BOE on 8 June 2026, so guides that call that number mandatory are out of date. Regional tourist registers and licences are separate and continue to apply.
Size the cabin for the group, not the beds
A villa that sleeps ten does not need a ten-seat cabin. A sauna is a small-group activity, and the rest of the party will be at the pool or in the kitchen. A four-seat cabin (€9,700–14,000) serves two couples or a family; a six-seat cabin (€14,000–19,500) suits a larger party. If the cabin is full, the card says that people take turns of fifteen minutes. Size for the group you picture on the last night, not for the bed count in the listing.
The card at the pool, in sixty words
A card like this fits in a frame by the door. We write one for your villa and your language.
Quiet hours for the compressor
A chiller cycles through the night as well as the day, and a villa has bedrooms. Place the machine where no bedroom window opens onto it, ask the maker for its sound level in dB(A) at a stated distance, and put quiet hours on the card if the pool is close to a neighbour. A housing that guides the air without trapping it quietens the machine; a closed cupboard only makes it hot. We draw the position of the plant on the plan before the pools, because moving it later is the expensive way.
Opening, closing and winter
| When | What the owner or manager does |
|---|---|
| Start of season | restart the plant, check the covers, test the display against a thermometer, rinse the coil |
| Between lets | the changeover routine, on the card, in twenty minutes |
| Long gap | cover both pools, switch the heater off at the board, leave the chiller on its low setting or drain per the handover |
| End of season | service visit: chiller, heater, seals, covers |
Insurance, safety and the neighbours
Ask your insurer what a plunge pool and a heated cabin require. Ask your management company about house rules. Put a lockable cover on the pool, a gate or a lockable door between house and terrace if children may come, and a notice at the pool that says to ask a doctor if unsure. Tell the neighbours what hours the cabin is used and what the compressor sounds like.
A word to the cleaner, and to the property manager
The cleaner and the property manager are the people who make or break a circuit in a let. Walk them through it once, with the plant room door open, and leave them a card with photographs: where the covers go, what the display should read, which switch is which, and who to message if something looks wrong. Reward the cleaner's time: twenty minutes is not nothing at the end of a long changeover day.
Cost of ownership, line by line
| Line | What it is | How to estimate |
|---|---|---|
| Energy | the heater while it heats and in use; the chiller while it runs | kWh per session block times your tariff; see the energy note |
| Cleaning | ten to twenty minutes per changeover for the circuit | your cleaner's rate times the extra minutes |
| Water care | filter, disinfection, top-ups, covers | a service visit or a routine on a card |
| Service | the annual check of chiller, heater and seals | our two-year warranty, with assisted visits in the first year; after that, yours |
Local detail for lets sits on the pages for Marbella and the Costa del Sol, the Algarve and Costa Blanca and Valencia.
Is a sauna worth it in a holiday let?
We do not quote a return, because we have no source for one. What we can say is that it changes what the listing can truthfully show and what guests do on the terrace.
Who looks after it between guests?
The person who already looks after the pool, with a one-page routine and a labelled photograph of the plant room.
Can I phase it?
Yes: the pair first, the cabin the next winter, on a plant space drawn for both.
Further notes
Notes that continue this one
The 38/4 pair, step by step
The routine, the plant behind it, the arithmetic of heating 1,800 litres and a plain safety note.
Read on
Single-phase or three-phase at the villa
Amps for a heater and a chiller, when single-phase is enough and what to ask your electrician.
Read on
Outdoor sauna permits, country by country
What we could verify on official sources in four countries, and the five questions to put to any town hall.
Read on