Coupled heat, air and moisture transfer - the base of the durability of facade repair systems
Haeulp, P., Neue, J. and Fechner, H.
1997 International Series on Advances in Architecture, v 3, p 255-259
Haeulp, P., Neue, J. and Fechner, H., (1997), "Coupled heat, air and moisture transfer - the base of the durability of facade repair systems", International Series on Advances in Architecture, v 3, p 255-259.
The coupled heat, air, moisture and contaminant transfer in porous materials plays a key role for the research of reasons of the mechanical, physical, chemical and biological degradations on the on hand, and the diminution of thermal resistance of building structures on the other hand. Based on the energy, mass and linear momentum conservation laws, a system of coupled nonlinear transport equations including a suitable computer code have been developed to calculate the moisture, temperature, ice, vapour pressure and air pressure fields. The performance of the solution is demonstrated for a historical building with worth-preserving clinker and sandstone facades. For example, a capillar-active calciumsilicate inside insulation halves the thermal transmittivity, but the condensation water which has formed on its cold side will be distributed. This structure is hygienically favourable, reliable and durable, and it keeps the low heat transmissivity.