Delivered flat-packed for self-assembly, with free UK mainland delivery on qualifying orders. Allow a full weekend for assembly and have at least one other capable adult available to help. Larger, heavier and multiroom models may require additional time and lifting assistance. A solid, level base and suitable delivery access are required.

For a complete setup, select Professional Installation and choose your preferred date, allowing for the stated production lead time. We’ll then arrange the installation around your requirements, including any additional preparation or works needed to accommodate your sauna where possible. Worth running our sauna build checker before delivery day, and our heater size calculator to confirm the heater this one needs.

Inside, this sauna holds about 15.5 m³ of air, about the size of a single bedroom. To get that properly hot you want roughly 15kW of heat, and the HUUM HIVE 15kW with Wi-Fi is the one we'd point you at. Anything between 15kW and 18kW will do the job, so it comes down to how it looks, how you control it and what you want to spend. Our heater size calculator shows how we got to that and lists every heater that fits this model.

This is a powerful heater and needs a three-phase supply, a heavier duty connection most homes don't have. Check this before anything else, because arranging one takes the longest of any job here. Whichever heater you pick, check what it needs before you buy.

The heater gets wired straight into your electrics by a qualified electrician. Never a plug, never an extension lead. If you're near us in Leicestershire we can arrange the electrician for you for a fee, so it's all done in one go. There's more detail in our full guide to electric heater setup.

Two things worth doing before you buy: our running cost calculator tells you what a session will cost to heat, and our solar calculator works out the panels and battery you'd need if you'd rather run it from the sun.

Inside, this sauna holds about 15.5 m³ of air, about the size of a single bedroom. The HUUM HIVE Wood 17kW is the stove we'd suggest for it, and anything from the 17kW to the 26kW will work. Our heater size calculator shows how we worked that out and what else fits.

A wood stove needs no electrics at all, but it does get extremely hot. It has to sit a set distance from the timber walls and benches, usually with a heat shield behind it, and something fireproof underneath in case an ember drops out. The stove instructions give you the exact distances. The walls are 42mm solid timber with no insulation layer, so it takes a bit longer to warm up and uses a bit more wood than an insulated one.

The chimney runs up and out through the roof. This one has a rounded roof, so the collar has to be shaped to match it or rain will get in. The fire also needs air to burn, and the room needs a vent low down and another high up so fresh air comes in and damp gets out. Have a think about where the smoke will blow, in relation to your house, your neighbours and where you sit outside.

Before you build, run our sauna build checker. It checks your vents, bench heights, clearances and drainage in a couple of minutes and flags anything that'll cause you grief later. Our full guide to wood-fired heater setup covers the rest. It's also worth a quick check with your council, as some areas have rules about chimneys and smoke.

A sauna of this scale, with its three-room layout, rewards a genuinely organised maintenance approach given the considerable surface area across the heat room and additional spaces. After every session, prop the heat room door open for twenty to thirty minutes to let moisture escape fully, the most effective habit for preventing mould and dark staining regardless of structure size. Wipe benches down once cooled, and sand the interior lightly once or twice a year wherever group use creates the most contact wear.

The additional rooms within the three-room layout should be checked separately for general dampness and wear given their different functions and exposure. Windows need only a standard glass cleaner and soft cloth.

Externally, treat the full Spruce exterior on a two to three year cycle, though a structure this size is genuinely worth tackling in sections across a season rather than all at once. Check the full extended base perimeter carefully for debris and standing water, given the considerably larger footprint this deepest variant occupies compared with other Agnes models.

Production takes 10-12 weeks, plus 1-2 weeks dispatch time for haulage. Due to its size and weight, this sauna ships on an oversized pallet (typically around a tonne or more) and arrives kerbside on a flatbed truck. Free UK mainland shipping applies, but additional charges may apply by postcode for length, weight, or restricted access, quoted separately.

Because of its size and weight, this item cannot be unloaded by tail lift and unloading is not included in the price — it needs arranging in advance. Depending on your access, you have three options:

• Forklift – if there's space to move the pallet from the truck to its final position, this is the most cost-effective choice.
• HIAB – for lifting over a fence or wall near the road, a HIAB (truck-mounted crane) is a practical and affordable option.
• Crane – if the final position is far from the road and forklift access isn't possible, a crane will be needed.

Handballing is possible but requires a full team of able helpers and suitable lifting equipment at every stage, and is done at your own risk. We can help source a forklift, HIAB, or crane in your area for an additional fee — if you're unsure which suits your site, contact us before ordering and we'll advise. Please have a solid, level base and clear access ready before delivery. Final positioning is not included unless you use our installation team; once unloaded, moving and positioning the goods is your responsibility.