Wall-Base Ventilation System to Control Rising Damp: A Case Study of Vilar de Frades Historical Church in Portugal

Moisture transfer in the walls in direct contact with the ground leads to the migration of soluble salts, which are responsible for many building pathologies. The treatment of rising damp in historical heritage walls is a very complex procedure. The traditional techniques currently used to minimize rising damp are, in most cases, slight effective or too expensive, especially when dealing with walls of considerable thickness and/or heterogeneous materials such as the historical monuments. The main purpose of this work is to present the experimental results of the rising damp treatment conducted, over 3 years, in the Vilar de Frades Church, in northern Portugal, using the wall-base ventilation technology. The results showed that, for this particular climate conditions, the best solution is to operate seasonally, with outside air admitted to the system during summer months and inside air admitted to the system during winter months.