Property Maintenance Guide for Humid Climates

Control indoor humidity first

Target 40-50% relative humidity indoors year-round. Above 60% you are in mold territory regardless of whether anything has leaked. A $15 hygrometer in two or three rooms is the cheapest diagnostic tool you can own.

• Run bathroom exhaust fans for 20 minutes after every shower, not 2
• Confirm bath and dryer exhausts terminate outside — not into the attic
• Do not oversize replacement HVAC equipment; oversized systems cool without dehumidifying
• Add a whole-home dehumidifier if humidity stays above 55% with the system running

Ventilation

• Keep soffit vents clear of insulation — baffles cost almost nothing
• Verify attic ventilation meets roughly 1 sq ft of net free area per 300 sq ft of attic floor
• Never seal crawl space vents without installing encapsulation and a dehumidifier
• Leave interior doors open where possible so conditioned air reaches every room

Drainage and grading

• Maintain 6 inches of fall over the first 10 feet away from the foundation
• Extend downspouts a minimum of 6 feet from the wall
• Keep flowerbeds and mulch below the weep holes in brick veneer
• Move irrigation heads so they never spray the foundation or siding
• Clear French drains and area drains annually

For landlords and property managers

1. 1Photograph unit condition at every turnover, including under sinks and behind appliances
2. 2Replace supply connectors at turnover rather than on failure — it is cheaper than one loss
3. 3Give tenants a written leak-reporting procedure and a number that is answered
4. 4Schedule HVAC condensate service across the portfolio each spring
5. 5Install point leak sensors at water heaters and laundry in every unit
6. 6Carry sewer backup coverage; it is excluded by default on most policies