Garden Shed Winter Moisture & Ventilation Simulator

Structural Controls Shed Parameters

Foundation Elevation

Ground Dampness

Painted Floor Underside Plywood / OSB vapor-seal barrier

Low Intake Vent Bottom air opening with mesh screen

Roof Wind Turbine Non-electric spinning whirlybird

Firewood Stored Inside Timber seasoning moisture source

Wood Pallet / Air Gap Keep logs off floor contact

Outdoor Ambient RH 88%

Mulch Perimeter Barrier Diverts roof runoff splashing

Architectural Cross-Section Cutaway

Air Current

Ground Vapor

Condensation

Moisture Balance Proof Live Psychrometrics

MOLD ROT RISK INDEX

High Mold Risk

Interior RH

86 %

Air Exchange Rate

0.2 ACH

Firewood Moisture

24.5 %

Dew Point Margin

0.8 °C

Severe condensation hazard: Cold damp soil drives upward ground vapor directly through the unsealed floor. In stagnant air (<0.5 ACH), firewood absorbs excess dampness, preventing seasoning and corroding stored metal tools.

Diagnostic Checklist

Foundation: Directly resting on soil (Wet)
Floor Seal: Raw wood OSB (Permeable)
Cross Flow: Stagnant infiltration only
Firewood: Trapping interior condensation