Celsium Jonas Classic 4 Person Outdoor Sauna

No. The £11,100 price is for the sauna in Shou Sugi Ban, delivered flat-pack, without a heater. Choose a heater in "Design your sauna": electric heaters from the Harvia Steel Top M90 (£400) to the HUUM HIVE Mini (£2,200), or a wood-burning Harvia M3, Pro 20 or Legend 150 with a stainless chimney. Every heater price includes the stones.

Final wiring must be completed by a qualified electrician; electrical connection is not included with sauna assembly.

The base price includes the hand-crafted sauna structure, panoramic glass facade, dimmable LED lighting, delivery to mainland England and Wales included in the product price, and 5-year warranty. It excludes the heating system (heater & chimney), which you select separately based on your preference for electric or wood-fired options.

Scottish delivery supplements and exclusions apply by postcode and are shown at checkout.

Each Jonas is made to order in Lithuania. Production takes about 4–6 weeks, then about 1–2 weeks for transport, so allow 6–8 weeks for flat-pack and a little longer for fully assembled. The estimate near the Add to Cart button shows the current delivery window.

Yes. The premium timber walls and panoramic glass are engineered for UK weather, including rain, frost, and wind. Regular maintenance (oiling, cleaning) preserves the finish and extends longevity. Natural timber movement and colour shifts are normal and not covered under warranty.

The Jonas Classic needs a 9–11 kW heater. It runs on a standard UK single-phase supply: most homes can take up to 11 kW on a dedicated circuit from the consumer unit. Three-phase is only needed for larger heaters. Your electrician will size the cable for your run and check your supply. We send all heater manuals in advance so you can share them with your electrician, and installation must comply with BS 7671 (UK wiring regulations).

Yes, left or right at no extra cost. The side is as seen from outside, facing the glass front, and the sauna is built to the side you choose, so please check it against your site plan before ordering.

Flat-pack delivery is the standard option. The sauna arrives as one crate of about 1.15 × 2.5 × 2.45 m high and about 1,100 kg, and we unload it for you. Depending on your access we use a tail-lift, forklift or HIAB, or unpack it by hand if access is tight; we confirm which after reviewing your access photos once you’ve ordered. You can use your own carpenter or our installation team.

Fully assembled delivery (+£1,550) means the sauna arrives built, ready to lift into place. Crane, forklift or HIAB unloading is not included; we can arrange it for an extra fee depending on access. Celsium recommends assembled delivery wherever access allows.

For Heracles assembly, use the Request an Installation Quote link under Add to Cart and complete the form for an exact price.

Yes. Celsium gives a 5-year parts-only warranty on the sauna structure and 2 years on other parts, for residential use. Labour and site visits are excluded. Heaters are covered by their manufacturer (HUUM 3 years, Harvia 2 years for private use). Natural timber movement such as small cracks and colour changes from outdoor exposure is not covered.

Yes. In "Design your sauna" you choose the exterior wood (Shou Sugi Ban as standard, or Thermo Pine), exterior colour, four glass finishes with single or double glazing, interior walls and a feature wall, bench wood and layout, backrest, lighting, and an electric or wood-burning heater. Every option shows its price before you add it.

Outdoor saunas are not maintenance-free. As a minimum, owners should be prepared to inspect and re-treat exposed timber at least every 12 months, or sooner if the manufacturer manual and local conditions require it.

You should also expect normal upkeep such as keeping the sauna clean and ventilated between uses, and making minor door or hinge adjustments over time in line with the manual.

In coastal or sea-air environments, exposed metal parts should be checked more regularly and protected with a rust-proof treatment such as WD-40 or another suitable anti-corrosion product.

Sauna heaters also require maintenance in line with the manufacturer manual. This normally includes periodically checking, washing, and restacking the stones, and in the longer term electric heater elements may need replacing if they wear out.

We do not currently offer a formal maintenance programme.

No. Our installation team can assemble the sauna, but the heater and any other electrical components must still be connected by a qualified electrician.

You will need a suitable electrical supply and, at minimum, an isolator switch. Full details are provided in the Electrical Supply section on the product page.

Yes. Any qualified electrician should be able to connect the sauna, provided they follow the electrical requirements listed in the Electrical Supply section of the product page.

After you place your order, we also send further information that you can pass on to your electrician.

In some cases, we may be able to share details of electricians who have connected saunas for previous customers.

Availability will depend on your location, and you are also welcome to use your own qualified electrician.

Assembly time depends on the model, access and site conditions. Many outdoor saunas can be assembled in around one day, while larger or more complex models may take longer.

Use the Request an Installation Quote link under Add to Cart and complete the form. We will confirm the expected installation time with your quote.

Yes. Our installation team uses specialist carpenters and installers who are experienced in assembling outdoor saunas, which is one of the reasons many customers prefer professional installation.

No. We do not carry out site visits.

To request an installation quote, use the Request an Installation Quote link under Add to Cart and complete the form with photos, measurements, site plans, access details and the proposed sauna location. Our installation team will use that information to assess access, base preparation and positioning, and flag any obvious issues before installation.

In outdoor saunas, it is normal for the timber structure to respond to changes in temperature, humidity, and ambient conditions over time. This can occasionally cause minor movement in the door opening, which may affect how the door closes or sits within the frame.

For this reason, sauna door hinges are designed to be adjustable. Minor door or hinge alignment adjustments over time are normal and should be carried out in line with the manual as part of routine ownership maintenance, rather than being treated as a product fault.

We do not currently have a full showroom, but many of our existing customers are happy to show their sauna to prospective buyers.

If you would like to see one in person, please contact us and we can try to arrange a viewing with a customer in or near your area.

Yes. Outdoor saunas are not maintenance-free.

As a minimum, owners should expect to inspect and re-treat exposed timber at least every 12 months, or sooner if the manufacturer manual and local conditions require it.

You should also expect to make minor door or hinge adjustments over time in line with the manual, as timber structures naturally move slightly with changes in temperature and humidity.

In coastal or sea-air environments, exposed metal parts should be checked more regularly and protected with a rust-proof treatment such as WD-40 or another suitable anti-corrosion product.

Sauna heaters also require maintenance in line with the manufacturer manual. This normally includes periodically checking, washing, and restacking the stones, and in the longer term electric heater elements may need replacing if they wear out.

We do not currently offer a formal maintenance programme.

If your sauna has exposed or untreated exterior timber, use a breathable, UV-resistant and water-resistant exterior wood treatment. We recommend Tikkurila Valtti Plus Kesto or Tikkurila Valtti Plus Color. If you prefer a clear, natural finish, Osmo UV Protection Oil is a good option.

Apply the treatment after assembly and before regular use, then inspect the timber annually and re-treat it as required for the product and your site’s exposure.

For sauna-room walls, window frames and door frames, use Tikkurila Supi Sauna Finish or Tikkurila Supi Sauna Wax. For benches and backrests, use Tikkurila Supi Laudesuoja Bench Protection. Never use ordinary exterior paint, varnish or household wood treatments inside the heated sauna room.

If your sauna has factory-finished or specialist cladding, follow the supplied manual and do not overcoat it unless the manufacturer confirms the product is suitable.

These recommendations are general guidance. Check both the sauna manufacturer’s manual and the treatment manufacturer’s instructions, and satisfy yourself that the product is suitable for the timber and any existing finish before applying it. If you are unsure about a colour, request samples from the manufacturer or retailer and test one on a spare timber offcut or a small, inconspicuous area first.

Buy one 2.7-litre tin (2.7 litres total) of Tikkurila Supi Sauna Wax for the sauna-room walls and ceiling, and one 1-litre tin (1 litre total) of Tikkurila Supi Laudesuoja for the benches and backrests.

The Jonas exterior is supplied in the selected factory finish. Buy no separate exterior treatment before first use and do not overcoat it until Celsium confirms a compatible maintenance product.

The buying calculation uses 19.56 m² interior requiring 2.25 litres, and 3.06 m² of bench timber requiring 0.44 litres. It uses the lower published coverage rate and one coat inside, with a 15% allowance. Glass, roof shingles or membranes, the underside and confirmed factory-painted trim are excluded.

These are conservative buying allowances. Follow the current label and technical sheet for the product you choose; if its coverage or coat count differs, use those figures instead.

Yes. Our traditional saunas are suitable for commercial use, and we already supply many commercial customers.

Commercial use requires a regular maintenance regime, as it would with any sauna. This includes cleaning the sauna, inspecting and maintaining the heater stones, and re-treating or painting the timber when required. The frequency will depend on usage, location and the manufacturer's maintenance instructions.