Houses require thorough ventilation and sunlight in every room, particularly sleeping areas.

Original passage

In the building of houses it is especially important to secure thorough ventilation and plenty of sunlight. Let there be a current of air and an abundance of light in every room in the house. Sleeping rooms should be so arranged as to have a free circulation of air day and night. No room is fit to be occupied as a sleeping room unless it can be thrown open daily to the air and sunshine. In most countries bedrooms need to be supplied with conveniences for heating, that they may be thoroughly warmed and dried in cold or wet weather.