TABLE 2.

Physical measurements of the five stone substrata employed in this study.

Substratum	Thermal Conductivity (W m–1 K–1) @ 30°C	Internal surface area (m2/g)	Internal pore volume (mm3/g)	Overall porosity (%)	Surface roughness (Ra, μm)
LIMESTN	0.44	0.099	8.27	6.95	2.21
MARBLE	0.45	0.0025	0.79	0.43	1.79
SANDSP	0.40	0.98	61.87	31.91	8.07
SANDSV	0.41	2.02	6.83	19.29	6.56
GRANITE	0.45	0.13	0.96	6.28	3.30
CONCRO		4.05	19.38	4.44	25.15
CONCTN		3.79	20.12	4.63	6.81
CONCTR		3.34	21.29	4.86	11.84

Note concrete coupons were not able to be measure for thermal conductivity using our laboratory protocols/equipment.