Specification

Outdoor Sauna Cladding Options: Thermowood, Thermo Ayous, and Black Charred

A guide to the three external cladding options available on Wellness One outdoor saunas — Thermowood Oiled, Thermo Ayous, and Black Charred — covering appearance, durability, and maintenance.

By Wellness One Lifestyle · Published 2026-08-02 · Updated 2026-08-02

Cladding Options for Wellness One Outdoor Saunas

The external cladding of your sauna is the first thing you see and the surface that faces the UK weather every day. Wellness One offers three cladding options, all using thermally modified timber for maximum durability.

Thermowood Oiled (Standard — Included)

Thermowood Oiled is the standard cladding included in the base price of every Wellness One sauna. It is a warm, honey-toned timber with a rich oiled finish. Thermowood is thermally modified Scots pine or spruce — the thermal modification process makes it highly resistant to moisture and rot without the use of chemicals.

Appearance: Warm honey-brown tone with natural grain character. Maintenance: Annual re-oiling with a suitable outdoor wood oil. Durability: 25+ years with proper maintenance.

Thermo Ayous (+£900 + VAT)

Thermo Ayous is a premium upgrade cladding. Ayous (also known as Obeche) is a light-coloured African hardwood that, after thermal modification, takes on a pale, silvery-grey tone. It is lighter in appearance than Thermowood and has a more refined, contemporary aesthetic.

Appearance: Pale silver-grey tone with fine grain. Maintenance: Light annual oiling. Durability: 25+ years with proper maintenance.

Black Charred (+£1,800 + VAT)

Black Charred cladding is inspired by the Japanese Shou Sugi Ban technique of charring timber to create a durable, weather-resistant surface. The charred surface is sealed and treated, creating a striking matte black exterior that weathers beautifully over time.

Appearance: Deep matte black with subtle texture. Maintenance: Minimal — the charred surface is naturally resistant to moisture and UV. Durability: 25+ years with minimal maintenance.

Which Cladding Is Right for You?

All three cladding options are thermally modified and will perform equally well in the UK climate. The choice is primarily aesthetic. Thermowood Oiled suits traditional garden settings. Thermo Ayous suits contemporary or Scandinavian-influenced gardens. Black Charred makes a bold architectural statement.