Buying a sauna is a significant investment, with prices ranging from under £2,000 for a compact indoor model to well over £30,000 for a bespoke commercial installation. Yet many buyers focus on the wrong things.

They compare size, colour or price while overlooking the details that will determine how enjoyable, durable and efficient the sauna will be over the next 20 years.

Whether you're buying an indoor sauna, outdoor sauna, barrel sauna or commercial wellness installation, this guide explains exactly what you should be looking for before making your investment.

1. Choose the Right Type of Sauna

The first decision is whether you want a traditional Finnish sauna or an infrared sauna.

Traditional saunas heat the air using an electric or wood-burning heater before allowing you to create löyly (steam) by pouring water over heated stones. Temperatures typically range from 70–100°C.

Infrared saunas work differently. They use infrared panels to warm the body directly and generally operate between 40–60°C. While many people enjoy infrared saunas, they don't recreate the authentic Finnish sauna experience.

Sauna Type	Best For
Traditional Sauna	Authentic sauna bathing, steam, contrast therapy
Infrared Sauna	Lower temperatures and gentle heat
Hybrid Sauna	Buyers wanting both experiences

2. Indoor or Outdoor?

Your available space will often dictate the best option.

Indoor saunas fit neatly into bathrooms, home gyms and wellness rooms, while outdoor saunas create a dedicated retreat and naturally complement cold plunges, outdoor showers and ice baths.

Indoor Sauna	Outdoor Sauna
Uses existing internal space	Creates a standalone wellness retreat
Easier utility connections	Greater installation flexibility
Protected from weather	Better connection with nature
Faster installation	Can become a garden focal point

3. Timber Quality Is Everything

The timber is the structure of your sauna. It affects insulation, longevity, appearance and how the sauna performs after thousands of heating and cooling cycles.

Premium manufacturers generally use slow-grown Nordic spruce, thermowood, alder, aspen or thermo-aspen because these species remain dimensionally stable and resist warping when repeatedly exposed to heat and humidity.

Cheaper saunas often use faster-grown timber or lower grades containing more knots and inconsistencies. They may look attractive when new but can be more prone to movement, cracking and shrinkage over time.

4. Don't Compromise on the Heater

Your heater is arguably the most important component in the entire sauna.

It determines:

• Heat-up time
• Steam quality
• Temperature consistency
• Running costs
• Reliability
• Overall comfort

Leading European manufacturers such as Harvia, HUUM and Saunum each offer different strengths.

Harvia is renowned for dependable Finnish engineering, HUUM combines striking Estonian design with generous stone capacity, while Saunum has introduced patented air-mixing technology that circulates heat throughout the sauna, helping eliminate the common problem of hot heads and cold feet.

5. Stone Capacity Matters More Than Most Buyers Realise

Many buyers compare heater power but overlook stone capacity.

A larger stone mass stores more thermal energy, allowing you to create softer, richer and longer-lasting löyly without causing dramatic temperature fluctuations.

Generally speaking:

• More stones = softer heat.
• More stones = better steam.
• More stones = greater heat retention.
• More stones = a more traditional sauna experience.

6. Wall Thickness and Insulation

A well-built sauna reaches temperature faster, uses less electricity and places less strain on the heater.

Look for:

• Thick wall construction
• Proper insulation
• Vapour barriers where appropriate
• Tight-fitting doors
• Double-glazed safety glass
• Quality seals

Good insulation improves comfort while reducing long-term running costs.

7. Ventilation Is Essential

Even expensive saunas perform poorly without proper airflow.

Correct ventilation helps:

• Maintain fresh oxygen.
• Improve steam quality.
• Prevent stale air.
• Help timber dry after use.
• Reduce moisture build-up.

Poor ventilation can make even a premium sauna feel uncomfortable.

8. Seating Layout

Ignore the advertised capacity and study the bench layout instead.

Ask yourself:

• Can everyone sit comfortably?
• Can somebody lie down?
• Are there multiple bench heights?
• Is there sufficient legroom?
• Is access around the heater easy?

A thoughtfully designed four-person sauna often feels significantly more spacious than a poorly designed six-person model.

9. Roofing Quality Is Often Overlooked

For outdoor saunas, the roof is your first line of defence against the British weather.

High-quality roofing protects the timber from prolonged moisture exposure, UV degradation and standing water.

Look for roofing materials such as:

• EPDM rubber membrane
• Premium asphalt shingles
• Heavy-duty bitumen roofing
• Powder-coated steel flashings
• Aluminium drip edges

Cheaper roofing materials can deteriorate much sooner, increasing the likelihood of leaks and reducing the overall lifespan of the sauna.

10. Check the Joinery

A sauna continually expands and contracts as temperatures rise and fall.

Well-engineered joinery allows this movement while maintaining structural integrity and weather resistance.

Signs of quality craftsmanship include:

• Precision tongue-and-groove boards
• Tight corner joints
• Flush bench construction
• Clean machining
• Properly aligned doors
• Stainless steel fixings

Good joinery is one of the clearest indicators of a premium sauna.

11. Barrel Saunas Should Have Adjustable Tension Bands

If you're buying a barrel sauna, look carefully for stainless steel tension bands, sometimes called compression bands or barrel bands.

These adjustable steel bands wrap around the outside of the barrel and help maintain the sauna's shape as the timber naturally expands and contracts throughout the seasons.

Over time, the adjustment bolts can be tightened to keep the timber compressed and minimise gaps between the staves.

Without them, the barrel can gradually loosen as the wood settles.

Without Tension Bands	With Adjustable Tension Bands
Greater timber movement	Better structural stability
Increased risk of gaps	Maintains barrel shape
More maintenance	Easy seasonal adjustment
Reduced weather resistance	Better long-term sealing

12. Look Beyond the Photographs

Many saunas look almost identical online.

However, what lies beneath the photographs can vary enormously.

Some lower-cost imported saunas are manufactured to aggressive price points, which can mean compromises in areas buyers rarely notice until years later, such as timber grade, wall thickness, hardware quality, roofing, insulation and quality control. That doesn't mean every Chinese-manufactured sauna is poor quality, but it does mean buyers should evaluate the specification carefully rather than assuming similar-looking products are built to the same standard.

Established European manufacturers generally invest heavily in engineering, precision machining, replacement parts, safety certification and long-term durability.

Rather than asking "Where was it made?", ask:

• What timber is used?
• How thick are the walls?
• Which heater is supplied?
• What roofing system is fitted?
• Are the hinges stainless steel?
• Is replacement glass available?
• Are spare parts stocked in the UK?
• What warranty is provided?

13. The Small Details Separate Premium Saunas

The best manufacturers pay attention to details many buyers never think to ask about.

Look for:

• Stainless steel hinges
• Marine-grade screws
• Tempered safety glass
• Hidden electrical routing
• Adjustable ventilation
• Premium door seals
• Thermally treated timber where appropriate
• Comfortable ergonomic backrests
• LED lighting designed for sauna temperatures
• Quality flooring and drainage

Individually these features may seem minor, but together they contribute significantly to the sauna's longevity and overall user experience.

14. Running Costs

The purchase price is only part of the investment.

Running costs depend on:

• Heater efficiency
• Insulation
• Sauna size
• Frequency of use
• Outdoor temperatures

A well-insulated sauna with a quality heater will generally cost less to operate over its lifetime than a poorly insulated budget alternative.

15. Safety Should Never Be an Afterthought

Look for:

• CE or UKCA compliance
• Overheat protection
• Timer controls
• Child safety features
• High-quality electrical components
• Comprehensive manufacturer warranties

These become even more important in commercial environments where the sauna may operate daily.

Premium Sauna Buying Checklist

Feature	What to Look For
Timber	Nordic spruce, thermowood, alder or aspen
Heater	Harvia, Saunum or HUUM
Stone Capacity	Larger stone baskets for softer heat
Insulation	Thick walls and quality vapour barriers
Roofing	EPDM membrane or premium shingles
Joinery	Precision tongue-and-groove construction
Barrel Sauna	Adjustable stainless steel tension bands
Hardware	Stainless steel fixings throughout
Ventilation	Adjustable inlet and outlet vents
Glass	Tempered safety glass
Warranty	Comprehensive manufacturer support
Spare Parts	Readily available in the UK

Common Mistakes to Avoid

❌ Buying purely on price.

❌ Choosing appearance over construction quality.

❌ Ignoring the quality of the heater.

❌ Overlooking insulation and ventilation.

❌ Buying a barrel sauna without adjustable tension bands.

❌ Failing to check the roofing specification.

❌ Assuming two similar-looking saunas are built to the same standard.

❌ Buying from a retailer that cannot provide long-term spare parts or technical support.

Final Thoughts

A sauna is far more than a timber cabin with a heater inside. The quality of the materials, engineering and construction will determine how well it performs for decades to come.

By looking beyond the photographs and marketing claims, and instead focusing on timber quality, heater technology, insulation, joinery, roofing, ventilation and structural details such as adjustable tension bands, you'll make a far more informed investment.

At Ice Cold Spice, we specialise in carefully selected premium European indoor and outdoor saunas from leading manufacturers. Every model in our collection is chosen for its build quality, performance and long-term reliability, helping homeowners and commercial wellness operators invest with confidence and enjoy an authentic sauna experience for years to come.