Window cleaning by the moon
Window cleaning by the lunar calendar: the next favorable day is Saturday 5 September. Score calendar, goals and the traditional rules behind every date.
Why by the moon?
Tradition promises streak-free windows under a waning moon — dirt is said to release more easily (Paungger/Poppe) — and on light days, when the moon stands in an air sign (Gemini, Libra, Aquarius).
On water-sign days folk tradition advises against window cleaning: streaks are said to remain no matter how thoroughly you work.
Read more: Paungger & Poppe (the Mondkalender classic) · The lunar calendar tradition (overview)
This month has 15 favorable days. The highest score falls on 3 September (90).
September 2026
gold = very favorable · gray = neutral · dark = unfavorableOctober 2026
Why 90 points on Saturday 5 September?
The MoonScore aggregates traditional lunar-calendar rules (Paungger/Poppe, folk tradition, Maria Thun). It does not represent any scientifically established effect.
* Traditions disagree on this rule — it counts at half weight.
When is the next good day for window cleaning?
Saturday 5 September — Very favorable (90/100).
When should you clean windows according to the lunar calendar?
According to Paungger/Poppe, windows are best cleaned during a waning moon — dirt is said to come off more easily then. Folk tradition additionally recommends light days, when the moon is in an air sign (Gemini, Libra, Aquarius).
Why avoid cleaning windows on water-sign days?
Folk tradition holds that streaks stay on the glass on days when the moon is in Cancer, Scorpio or Pisces. For a streak-free shine, the waning moon and air days are considered the best choice instead.
Never miss a full moon
One email the evening before every full moon. Nothing else.
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