Using the Transient Plane Source technique, various geopolymers, metakaolin-derived sodium (Na), sodium-potassium (NaK) and potassium (K), were tested to determine the effect of varying environmental conditions, such as temperature and humidity, on thermal conductivity. The results concluded that the thermal properties of the geopolymers derived from metakaolin are not greatly affected by the Si/Al ratio in the as-cured state. When the sodium geopolymers were tested at 50% relative humidity, the ...