ICON 125: 3 Person Cube Sauna with Glass Front
Two decisions, the heater and the roof colour. Everything else is in the price.
From £5,040.00
Kerbside pallet delivery to mainland UK included
About 14 weeks from order. We confirm the current figure in writing when you order.
- 8kW Harvia heater, its controls and 20kg of stones included
- Painted at the factory, so it arrives finished
- Kerbside pallet delivery to mainland UK included
Delivery & installation
Delivery to a mainland UK address is in the price. The cabin arrives as a flat pack kit on one pallet, 2.0m by 1.2m by 0.9m and about 500kg, on a lorry with a tail lift. The driver sets it down at the kerb or on the nearest firm, level, hard surface the pallet truck can reach; a pallet truck does not cross gravel, grass or a step. From there the parts move by hand, and two people carry everything.
Offshore addresses, the Scottish Highlands and islands, and any address a lorry cannot reach are quoted separately before anything is ordered, and if the figure does not suit you the order is cancelled and refunded in full at that point.
Installation is not in the price. It is optional, from £650, and we quote it for your site and confirm the cost before anything is delivered. Tick it when you order or ask us about it afterwards; either way nothing is booked until you have agreed the figure.
Returns
Until the order is placed with the factory you can cancel and be refunded in full, with no reason needed. Your statutory cancellation rights are set out in full in our returns policy.
Check the pallet on the day it arrives, count the parts against the list in the manual, and tell us about anything damaged or missing within 48 hours with photographs. Anything that arrives damaged or faulty is ours to put right. Missing parts found later during assembly are not caught by that window, so report those as you find them, one list, with photographs, and do not book an electrician or an installer for a fixed date until the delivery has arrived and been checked.
About this product
A three person outdoor sauna in thermo treated spruce, 2,050mm wide and 1,250mm deep, with the whole front wall in 8mm toughened bronze glass and the door set into it. It is the smallest cabin in the range with a full glass front, and the one whose pallet is small enough for a tail lift lorry to set down on an ordinary drive.
Why it is built without insulation
The sides and roof are 42mm solid staves and the back wall is 28mm tongue and groove. There is no insulation behind either, and that is the design rather than an economy. The mass of the timber is the insulation, which is how a stave built sauna works: it takes longer to bring up than an insulated cabin and it sheds heat faster once the heater is off. What you get in return is a cabin that behaves like a sauna rather than like a heated room, in a shape with no corners for heat to sit in.
Thermo treated spruce only. Thermo treatment is kiln modification with heat and steam rather than chemicals; it raises dimensional stability and resistance to rot, which is what a timber cabin standing in a British garden through a wet January is actually up against. The outside is painted at the factory before it ships, so it arrives finished, and the bitumen shingle roof comes in five colours at no difference in price. The cabin weighs about 500kg as a kit; add the heater, the stones and three adults and the loaded figure is nearer 800kg, which is the number to design the base around.
The heater, and the only decision to make
Two heaters, both supplied with their stones. The room is about 3.8 cubic metres, and because the walls are a single skin Harvia's sizing rule treats it as nearer six. Both heaters here sit at the bottom of their published range for a room that size, which is the right end to be at in a cabin with no insulation: it comes up to temperature quickly and the thermostat does the rest.
Harvia Vega BC80, 8kW. Fitted as standard. Rated by Harvia for 7 to 12 cubic metres, 20kg of stones, timer and thermostat as two dials on the heater. It needs a dedicated circuit installed and certified by an electrician: 35 amps single phase in 6mm² cable, or 3 × 16A on three phase, and a room containing a sauna heater is a special location under Approved Document P, so the work is notifiable in England. That visit is a separate cost. We would rather tell you here than after you have ordered.
Huum Drop 9, 8.5kW, with app control. Rated by Huum for 8 to 13 cubic metres and it holds 55kg of stone against the Harvia's 20kg. More stone holds more heat, so the steam is softer, it lasts longer between ladles and the heater cycles less. The UKU control runs it from an app, so the cabin is hot when you walk out to it rather than when you remember to go and switch it on. Made in Estonia, like the cabin. A dedicated circuit applies here too, sized by your electrician to Huum's data sheet.
Who this is actually for.
Every product here is described with the honest opposite beside it: who it suits, and who should be looking at something else. If none of the descriptions below fits you, the right answer is elsewhere in the range, or elsewhere entirely, and we would rather say so.
The whole front is glass, floor to roof, with the door set into it, and the cabin is 2.05 metres wide by 1.25 metres deep. Three adults sit on the full width bench at 730mm with their feet on the step. The 8kW Harvia heater, its 20kg of stones, the factory paint, the shingle roof in the colour you pick and the bucket, ladle and thermometer are all in the £5,040.
Worth confirmingyou want four people in it, or to lie down. The bench is 1.93 metres wide and the room is 1.05 metres deep. Three sit; nobody stretches out. The ICON 200 S is the next size up and it is the answer to both.
It arrives flat packed on one pallet and goes together with two people, a drill and the maker's instructions. The heater needs a dedicated circuit: 35 amps single phase in 6mm² cable for the 8kW Harvia, which is an electrician's job and not a plug. The Harvia's controls are two dials on the heater; the Huum option adds an app.
Worth confirmingyou want it delivered built, or holding its heat like an insulated cabin. The wall is a single 42mm stave with air on both sides, so it warms fast and cools fast, and on a January night the heater is working harder than it would in a cabin with insulated walls.
The product that gets used is the one worth recommending, and it is not always the largest one.
The measurements that decide it.
Read this before anything else. Things this size are almost never sent back because they were the wrong product. They are sent back because the pallet could not be set down, the parts would not reach the spot, or the ground under them was never going to hold them.
The pallet is the one to respect. It weighs about half a tonne and it moves on a pallet truck, which needs a hard, level surface from the lorry to wherever it stops. Gravel, grass, a kerb without a dropped edge or a single step all stop it. If the pallet has to stop at the road, the parts are carried from there by hand, and the two end walls with the glass in them are the ones to plan the route for.
From order to first use.
Here is each stage, and who does what. Before you order, email hello@tarnfell.com and we will confirm the current lead time for this cabin, delivery to your postcode, installation options, base requirements or anything else you would rather have settled first.
- Week 0
Order and site check
Base, access and your electrical supply are agreed before the order is placed with the factory. You arrange the base and the circuit. Nothing goes into production until the total for your postcode is confirmed in writing.
- Weeks 1 to 14
Built to order in Estonia
The cabin is made to order, painted on the outside at the factory, and packed on one pallet with the heater, the stones and the accessory set. About 14 weeks at the moment; we confirm the current figure in writing when you order and tell you where it is in the process rather than leave you to wonder.
- Delivery day
One pallet, set down at the kerb
A lorry with a tail lift sets the pallet, 2.0 × 1.2 × 0.9m and about 500kg, down at the kerb or the nearest firm, level spot the pallet truck can reach. Count the parts against the list that day and photograph anything damaged. You will want two people to carry them through to the base.
- Build
Frame, walls, staves, roof
The base frame goes down first, then the back wall and the glass front, the staves between them, the bench and the shingles on the roof. Two people, a drill and the maker's instructions. If you would rather hand it over, installation is optional from £650, quoted for your site and confirmed before delivery.
- After
Your electrician connects it
The Harvia BC80 needs a dedicated 35 amp single phase circuit in 6mm² cable, or 3 × 16A on three phase, installed and certified by a qualified electrician. That work is not included, and the cabin should not be used until it is done.
What owning one actually involves.
The handful of things that decide whether this is still in use in year three.
A flat, load bearing slab or paved base at least 1.4 by 1.1 metres, laid before the pallet arrives. The maker's drawing gives a base frame of 1,394 by 1,050mm with the support positions marked, and it is the frame that carries the cabin, so those are the points to bear on. The base is not included.
8kW at 230V is 35 amps on a circuit of its own, in 6mm² cable, installed and certified by an electrician before first use. On a three phase supply it is 3 × 16A. The Harvia's timer and thermostat are dials on the heater; the Huum Drop uses its UKU control and an app, and the control is part of that option.
A base frame, a back wall, a glass front with the door in it, the staves that make the sides and roof, the bench and the shingles, with the maker's instructions. Two people and a drill over a weekend. If you would rather hand it over, installation is optional from £650, quoted for your site and confirmed before delivery.
The outside is painted at the factory. A single skin cabin is not heated continuously, so the timber can pick up damp marks or surface discolouring over a wet winter, and solid staves move slightly with the seasons. Heating the cabin after wet weather and airing it after every session is most of the answer, and none of it affects the structure.
The running costs, with the working shown.
The purchase price is public; the running cost rarely is. Ours are published with the assumptions stated, so you can check the sums rather than take our word for them.
about £2.80
Heat up: 8kW × 0.6 h is 4.8 kWh, because 8kW brings a cabin this size up in a little over half an hour. Holding: 1.5 h at roughly half duty is another 6 kWh. That is 10.8 kWh at 26.11p, working shown in full so you can check it.
about £295
10.8 kWh × 2 × 52 is 1,123 kWh. Three evenings a week is nearer £440. Both figures move with your tariff and with the weather, which is why the unit rate and the assumptions are stated rather than buried.
no cost, one dial or one app
The Harvia's timer runs it for up to four hours, or starts it by itself up to eight hours ahead. The Huum Drop does the same from its app, from wherever you are. The heater only draws full power while it climbs; once hot, the thermostat cycles.
Assumptions: electricity at the Ofgem price cap unit rate of 26.11p per kWh, 1 July to 30 September 2026, including VAT; a little over half an hour to temperature at full draw on the 8kW heater; thermostat cycling near half power once hot. The wall is a single 42mm spruce stave with no insulation behind it, so heat up is slower and heat loss faster than in an insulated cabin, and on a cold, windy night the real figure sits above these numbers rather than below them. These are calculated from the heater rating, not measured in use. Rerun the sums at your own tariff.
What you have to do, and what the rules require.
Everything you have to do, and how often.
| Job | How often | Who |
|---|---|---|
| Install and certify the heater circuit 230V single phase, 35A, 3 × 6mm² cable, or 400V three phase, 3 × 16A, 5 × 2.5mm² cable for the Harvia BC80; the Huum Drop 9 to Huum's data sheet. Outdoor circuits and rooms containing a sauna heater are notifiable work in England. | Once, before first use | A qualified electrician |
| Lay the base A flat, load bearing slab or paved base at least 1.4 × 1.1m, bearing on the support positions in the maker's base frame drawing. | Once, before delivery | You, or a groundworker |
| Build the cabin and fit the shingles Base frame, back wall, glass front, staves, bench, then the bitumen shingles on the roof, following the maker's instructions. Fit the shingles the same day the roof goes on. | Once, over a weekend | You and one other, or an installer |
| Dry it out after wet weather Heat the cabin after rain and once a month if it is standing unused, to keep surface mould off the timber. Air it after every session. | After rain; monthly when idle | You |
| Look after the paint The outside is painted at the factory. Recoat as the finish needs it, every few years in an exposed spot. The inside is left bare. | Every few years | You, an afternoon |
| Check the stones Restack the stones once a year and replace any that have crumbled. Both heaters are supplied with their stones. | Once a year | You |
Where this comes from.
Regulation and guidance, linked so you can read it yourself. None of it is our opinion.
- Outdoor circuits and rooms containing a sauna heater are notifiable electrical workApproved Document P, 2013 edition
- Outbuildings within 2 metres of a boundary are limited to 2.5 metres in height under permitted developmentPlanning Portal, outbuildings
- Electricity price used in the running costsOfgem price cap unit rates
- Harvia Vega BC80 output, room rating of 7 to 12 cubic metres, 20kg stone quantity, fuse and cable ratings and 2m minimum room heightHarvia's published product data for the Vega BC80
- Huum Drop 9 output, room rating of 8 to 13 cubic metres, 55kg stone quantity and app controlHuum's published product data for the Drop
- Cabin dimensions, door size, bench heights and the base frame with its support positionsThe maker's dimension drawing for the ICON 125, sheet TIC20/125KE-PT01
Every figure the makers publish.
- Lead time
- About 14 weeks from order. We confirm the current figure in writing when you order.
Cabin figures from the maker's dimension drawing for this cabin and the maker's published product data, heater figures from Harvia's and Huum's published data. Where a figure is our own arithmetic it says so on the row.
What arrives, and what does not.
- The cabin as a flat pack kit: 42mm thermo treated spruce staves, the 28mm back wall, the full height glass front with the glass door in it, the bench and step, the floor and the base frame
- The Harvia Vega BC80 8kW heater with its built in timer and thermostat, and its 20kg of stones. Or the Huum Drop 9 with its UKU control and 55kg of stones, if you choose it
- Exterior paint, applied at the factory before it ships
- Bitumen roof shingles in the colour you choose, every screw and fixing, and the maker's assembly instructions
- The accessory set: bucket, ladle, thermometer and hourglass
- Delivery on one pallet to the kerb at a mainland UK address
- One point of contact for the order, the delivery and anything that goes wrong: us
- The base. A flat, load bearing slab or paved area at least 1.4 × 1.1m
- The electrical work. The 35 amp circuit is a qualified electrician's job and a separate cost
- Assembly, unless you take the optional installation, from £650, quoted for your site
- Moving the pallet beyond where the pallet truck stops. From there the parts are carried by hand
- Anything not on this page. What you see here is what arrives
Reasons to buy something else.
Delivery is by tail lift lorry to the kerb, and the pallet is 2 metres long and about 500kg. A shared private road, steps to the kerb, a gravel drive or a double parked frontage all need solving before you order, not on the day. From wherever the pallet stops, every part moves by hand, and the route needs to take the glass front.
The bench is 1.93 metres wide and the room is 1.05 metres deep. Three people sit; nobody stretches out. If four seats or lying down is the point, the ICON 200 S is the next size up and we will point you at it rather than sell you this.
A single 42mm stave with air on both sides loses heat far faster than an insulated wall. This cabin heats quickly and cools quickly, and in January the heater is working hard to hold 80 degrees. If year round evening use at the lowest running cost is the aim, the cross laminated timber cabins in this range cost more for exactly that reason.
It is a kit, and it needs two people, a drill and a weekend. Installation is optional from £650, quoted for your site and confirmed before delivery. If neither appeals, a cabin delivered built is the honest answer.
If any of these apply, say so and we will point you at what does suit you, including when that is a cheaper product or a different retailer.
What we know, and how we know it.
Not a rating. A record of where every figure on this page comes from: what we have checked against a published source, what the maker has confirmed in writing, and what nobody has measured yet. The states describe our evidence, not the product.
- Dimensions, door and base frame
-
Verified
Overall width, depth and height, door opening, bench heights and the base frame with its support positions, checked against the maker's dimension drawing for this cabin, sheet TIC20/125KE-PT01. Room volume is our own arithmetic from that drawing and is marked as such.
- Heaters and electrical supply
-
Verified
Output, room rating, stone quantity, fuse ratings and control type for the Harvia Vega BC80 and the Huum Drop 9, checked against each maker's published product data. Both are rated for rooms from 7 or 8 cubic metres; this cabin is about 3.8, or nearer 6 with the single skin allowance, so both run at the bottom of their range and the page says so. Both documents are linked in the sources list further up this page.
- Construction, timber and what is in the kit
-
Confirmed by manufacturer
Thermo treated spruce, the benches, the roof covering, the factory paint, the accessory set and the pallet size and weight: from the maker's own price list and its written confirmation of 11 September 2026. Stave thickness and the 8mm bronze glass front: from the maker's published product listing. None of it yet checked against an assembled cabin.
- Warranty terms
-
Information not yet published
The maker's warranty terms for this cabin have not yet been received in writing, so no warranty period is stated on this page. It will be added the day it is confirmed, and if it is shorter than you would expect we will say so.
- Lead time, assembly time and running cost
-
Not independently measured
About 14 weeks is the maker's current production figure and is confirmed per order rather than promised here. No independent measurement of assembly time, heat up time or heat loss exists for this cabin; the running cost figures are calculated from the heater rating and say so where they appear.
These states move as the evidence does. When a figure is measured on an installed cabin, by us or by an owner who shares the numbers, its state on this page changes to match, and the figure is corrected if it needs to be.
Weighing this against another sauna? Let us do the homework.
Choosing between two saunas takes evenings of research, so let us carry it. Name the other one you are considering and we will put the two side by side properly: sizes, heat, running costs, and what each asks of your garden and your fusebox. A written comparison or a call, whichever suits you, within 24 hours. And if the other one genuinely fits your space better, we will say so.