This literature review reports in-service moisture and temperature conditions of floor, wall, and roof members of wood-frame buildings and exposed wood decks and permanent wood foundations. A wide variation exists in reported wood moisture content, spanning a range from as low as 2% to well above 30%. Relevant studies are summarized, and measured values of wood moisture content and temperature are tabulated. Trends are discussed that relate moisture conditions to climate and season, moisture sources and transport mechanisms, and building design and construction.