This scatter-plot shows only daily maximum temperatures, indoors and outdoors, and displays the average values. The Manilla average outdoor maximum of 25.5° is already comfortable, if a little on the warm side. The average indoor maximum of 23.8° is closer to the ideal.
While this solar-passive house scarcely changes the average maximum daily temperature, it drastically reduces the extremes. The slope of the linear regression line shows that indoor maxima vary only 38% as much as outdoor maxima. This results from effective insulation and daily and seasonal storage of heat and coolness in thermal mass material through the year. In addition, the house is well shaded in summer, and catches warmth from the sun mainly in winter.
Dashed lines to the left and right show how the indoor temperature on the hottest days is reduced by up to 10 degrees, while on the coldest days it is increased by up to 8 degrees.
This post is one of a set of four back-dated to June 2010:
Indoor versus Outdoor Temperatures (1096 days)
Indoor versus Outdoor Minima (1096 days)
Indoor versus Outdoor Maxima (1096 days) (This post.)
Indoor/Outdoor Regressions for Maxima and Minima
This article was originally posted in the weatherzone forum thread “Indoor Climate” on 7th June 2010. It is backdated here to 19th June 2010.