Basement cleaning is about managing dust, moisture, and the conditions that allow mold to develop in a space that often doesn't see daily use.
01Concrete floor and walls
An unfinished basement floor and walls are swept and mopped with a concrete-safe cleaner. Pay attention to the corners where moisture and dust accumulate together. White efflorescence on walls — the white mineral deposits from water infiltration — is brushed off dry before mopping. Mopping over efflorescence with water can temporarily dissolve it and leave a harder deposit when it dries.
02Mechanicals — water heater and furnace area
The area around the water heater and furnace accumulates dust that affects equipment performance and can contribute to combustion issues in gas equipment. Vacuum the area around both units annually with a shop vac. Do not use standard household vacuums — the filters aren't adequate for the fine concrete dust present in basements. Wipe the exterior of both units with a dry cloth.
03Sump pit
A sump pit that's not regularly cleaned accumulates sediment and biological growth that eventually clogs the float or the pump intake. Remove the pump annually (with the circuit off), clean the pit walls and floor, clean the intake screen on the pump, and reinstall.
04Dehumidifier coil and filter
A dehumidifier running without a clean filter and clean coils removes less moisture and works harder. Check the filter monthly during peak humidity season and clean per the manufacturer's instructions — most are rinsed under water and dried. Clean the coils with a soft brush and compressed air annually.
Marcus Webb is a general contractor and home maintenance writer based in Columbus, Ohio. He writes about the repairs and installs that come up every year in every house — the practical, repeating work that keeps a home livable.