Swell Sport · Practical guide

Understanding water marks on sauna glass and timber

Before cleaning a water mark, record when and where it appears. The useful question is not only “How do I remove this?” but “Does it follow rain, bathing, cleaning or a particular water path?” A short observation sheet helps separate a one-off mark from a recurring condition that deserves inspection.

Swell Cedar Cube 2 in a home setting.

Map glass and timber separately

Take one overview of the doorway or wall, then close photographs of the mark. Label glass, timber, adjacent metal and seal lines separately. Write down whether the mark is on the inside or outside and whether the surface was wet when photographed.

The Cube 2 troubleshooting table lists rain or condensation on timber against water marks. Treat those as possible explanations to investigate, not an automatic diagnosis of any mark in any location. ^[1]

Use an event-based record

Create columns for first noticed; recent rain; recent sauna use; recent cleaning; nearby sprinkler activity; surface wet or dry; and whether the mark returned. Add a sketch of the visible path, starting at the highest observed wet point rather than assuming where the water entered.

Keep photographs from before cleaning. If a mark reappears, take a fresh set from the same angle. Record changes in size or position in words as well as images, since reflections on glass can make two photographs look very different.

Choose the next step from the pattern

A mark appearing after a single splash calls for the approved surface-care method. A repeated trail at the same joint calls for a joint inspection request as well as cleaning advice. Persistent dampness, a changed fitting or water near electrical equipment should move the job out of cosmetic cleaning.

For Cube 2, the manual says not to operate if wiring, plugs, control components or the heater appear damaged. If water has reached that equipment, leave the cabin out of use and have the relevant equipment assessed before restarting. Do not spray or open electrical enclosures to investigate. ^[1]

Keep the cleaning request material-specific

Ask for the approved product and method for the exact surface: glass, timber, finish, seal or metal. Include any coating already applied and the products used previously. The Cube 2 manual prohibits pressure washers and steam cleaners and says to avoid harsh chemicals. ^[1]

Do not escalate from a damp wipe to stronger products simply because a mark remains visible. Send the result to support and ask whether it is a cleaning issue or a condition requiring inspection. Avoid transferring a glass-cleaning method onto the timber below it.

Example: a repeating line below a corner

Suppose a mark appears below the same upper doorway corner after two rain events, including one when the sauna was not used. Your record says exactly that, with dated photographs and a view of the outside corner. It does not label the mark “condensation” or “roof leak”.

Ask the supplier which joint should be inspected and who should inspect it. The Cube 2 manual calls for monthly and post-heavy-rain inspection of external silicone at panel-to-stave joins, roof joins and exposed weather seals. Keep the inspection response beside the cleaning record so the reason for recurrence is not lost. ^[1]