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Did you know that badly maintained sauna stones can drastically influence the amount of energy wasted when heating up your sauna? Have you noticed a change in the time it takes for your sauna to reach temperature? Does the steam feel weaker when you pour water onto the stones of your heater? Are there small crumbles of stones in front of your heater? These signs indicate that it might be time to upgrade your sauna stones to fresh ones.
We at Finnmark Sauna, have answered four frequently asked questions about sauna stones that will help with the maintenance of your heater and ensure a pleasant sauna session. Afterall, you shouldn’t let degraded stones compromise the perfect “löyly”.
Sauna stones should be loaded into the heater so that they are just above the top rim of the sauna heater.
1. WHY should you change your sauna stones?
High quality stones are at the heart of an authentic sauna experience. The hot stones in the sauna heater create the renowned “löyly” which refers to the evaporated hot steam you get when water is thrown onto them.
Old and damaged stones may not only result in a disappointing “löyly” but can also damage the heating elements, waste energy (especially important to look at when trying to decrease energy costs) and compromise the air quality of the sauna. This is why sauna stones are recommended to be checked and upgraded every 1-2 years, depending on how often the sauna is used.
2. WHEN should you change sauna stones?
If sauna is a part of your weekly routine, the stones should be checked at least once a year. The more you use your sauna and the higher the temperatures, the more often the stones will need replacing. If you heat up the sauna at least twice a week, it’s best practice to unload the stones every six months. In case the sauna is not in use every week, once a year will suffice.
Before you check the sauna stones:
Make sure to check that the heater is switched off and the stones have fully cooled down before removing the stones. We recommend wearing gloves when unloading old stones from the heater. They will protect your hands from dust, any sharp edges of the heater and cracked stones.
Proper sauna stones create a pleasant warmth and humidity when water is poured on top of them.
3. WHAT are the signs of degraded sauna stones?
Visible signs of old sauna stones are changes in colour. Old stones may turn from dark grey to lighter grey, rusty brown, white or even green. Small crumbles of stones often end up on the floor in front of the heater. Some of the stones may have cracks in them or they have broken down into multiple pieces. You can test the sauna stones by gently tapping two stones against each other. The stones that crack or make a hollow sound should be discarded and changed to fresh ones.
Watch some of our videos on how to change your sauna rocks:
In another blog post, we have curated a number of videos on how to place sauna stones in your sauna heater. Take a look at one of them on how to load sauna stones into a Narvi NC electric sauna heater:
4. WHICH type of stones are used in sauna heaters?
The most important aspects of high-quality sauna stones are their shape, size and thermal conductivity. Grade A Finnish Olivine Diabase Stones or Vulcanite Sauna Stones are a great choice for any wood burning or electric sauna heater.
Olivine diabase is a traditional, high-quality sauna stone noted for its durability and excellent soft steam created when water is poured on top of it.
Traditional Olivine Diabase Sauna Stones are a great choice for any sauna heater.
Some heaters, such as the HUUM DROP, look great with the rounded Olivine Diabase Sauna Stones.
Vulcanite is a slightly darker coloured and durable igneous rock. It has a higher metal content, which helps it store heat and is ideal for sauna users who heat up the sauna multiple times a week and have the heater on for longer periods.
Vulcanite sauna stones are slightly darker in colour and have a higher metal content, making them durable.
Typically, sauna stones come in two sizes: 5-10 cm and 10-15 cm. You should always check what sized sauna stones are recommended for your heater. Generally, the smaller size is suitable for most electric heaters and the larger rocks for wood-burning heaters. However, there are exceptions to this.
If you are browsing Finnmark's collection of sauna heaters, you can check the recommended sauna stones in the heater model's product description or in the manual.
Although it may seem like a good idea to pick some stones from outside, you should never use just any stones in your heater. Specialised sauna stones, like the ones we mention above, have a high thermal capacity and metal content, making them suitable to use in the hot and humid conditions of a sauna. Regular stones have a high risk of cracking easily and damaging the heating elements. In a worst-case scenario, they can explode.
Decorative Cover Stones
Depending on the look and feel of your sauna environment, there are stone options that offer an aesthetically more rounded and smoother feel. Cover stones are used as a stylish surface finishing to your heaters' stones. These stones beautifully complete any sauna spa aesthetic for those wishing for a less rugged, more refined sauna experience. We offer rounded Finnish Olivine Diabase Stones and even white ceramic covers stones to perfect your sauna environment.
Rounded Olivine Diabase sauna stones inside the HUUM HIVE Electric Sauna Heater.
Get in touch with our team about your sauna stones:
If you want to know more about sauna stones or remain unsure of which stones you should get for your heater, feel free to get in touch with our knowledgeable team.
