Kivi™ Sauna Rocks 33lb

Sauna stones are the heat core of your sauna. They sit on the heater, store its heat through the session, and release it as steam when water hits them. Without them you get hot dry air, not the soft burst of löyly that defines a real sauna.

These are A+ grade vulcanite, a dense igneous rock of volcanic origin. Vulcanite is hard and graded specifically for sauna use, which is why it holds heat through a long session and stands up to repeated heating and cooling without breaking down the way softer mixed stone does.

One box holds 33 lbs of rounded stones averaging 2 to 3.5 inches, enough to fill most smaller home heaters in a single purchase. Heaters are rated by stone weight, not by stone count, so weigh the stones currently in your heater before ordering to confirm how many boxes you need.

A good sauna stone is dense, slightly porous igneous rock, graded for repeated heating and cooling. Density lets it hold heat and throw a full burst of steam, while porosity gives more contact area for water. A rounded shape and a 2 to 3.5 inch size let air and water move through the pile.

No. River, beach, or backyard rocks are the most common cause of stones bursting inside a heater. Highly porous and sedimentary rock traps water inside it, and that water turns to steam under high heat and can split the stone. Use only rock that is graded for sauna heat.

Vulcanite is graded for repeated heating and cooling, so it resists the thermal shock that makes cheap mixed stone pop or shatter. Individual stones still form hairline cracks over time. That is normal wear, not a defect. Pull out any badly broken pieces and the rest keep working.

Pouring water on the hot stones is what makes the steam. The water flashes to vapor on contact, lifts the humidity, and makes the heat feel fuller and more intense on your skin. This is the central ritual of a traditional sauna. Pour small amounts and build the heat gradually.

Add water a ladleful or two at a time, never a full bucket at once. Make sure the stones have fully heated first, or the water just sits and cools them. Let the steam clear before the next pour, and stop when the heat feels right for you.

You should always use warm or even hot water for löyly. Warm or hot water doesn't cool down the rocks too much, which ensures your stones stay blazing hot for even the longest sessions. Additionally warm water reduces the risk of thermal shock for stones which is the most common reason for stones cracking.

Never pour undiluted essential oil straight onto the stones. Neat oil can scorch, leave sticky residue, and even ignite on a hot heater. Instead mix a few drops into your water bucket and ladle that over the stones, or use a sauna-safe aromatherapy product made for heater heat.

Rinse the stones under water first to wash off shipping dust, then load them and run the heater once for about 30 minutes without pouring any water. This dry first heat-up clears any residue and lets trapped moisture escape, so your first proper session gives clean steam with no smell.

Stack them loosely rather than packed tight. Smaller stones at the bottom near the elements, larger on top, with gaps so hot air rises through the pile. Packing them tight blocks airflow, strains the elements, and weakens the steam. Cover the elements fully without burying them.

Sauna stones are mostly self-cleaning, since each heat cycle burns off sweat and residue. Every few months, rinse them with plain water and skip soap, which leaves a smell when heated. While they are out, pull any crumbled or cracked pieces, then restack and reheat before your next pour.

With typical home use of two to three sessions a week, plan to replace these stones every one to two years. Heat cycles slowly break stones down, they crumble and pack tighter, and steam output weakens. When löyly feels thin or stones look crumbled, swap in a fresh box.

Use them in any stone heater, electric or traditional wood-fired. They are not for pure infrared cabins, which warm your body directly and have no heater to hold stones. In a hybrid sauna that has both infrared panels and a stone heater, the stones go in the heater section only.