# Preliminary Valorization of Climatic Conditions Effects on
## 1 Introduction  
In the recent decades, conservation of the built heritage by compatible materials has become an important issue [1]. In conservation of built environment, repointing mortars are among the most important applications, as they protect the masonry in facing environmental threats [2]. Compatibility of lime-based mortars with many historical masonies has been discussed and confirmed by modern studies, thanks to their moderate stiffness and high permeability [3; 4; 5]. In fact, restorative application of historic mortars is highly recommended, as their compatibility for these applications have been frequently confirmed in the lab and in the field [6; 7; 8]. Addition of organics as historical and modern solutions have been carried out to improve the reaction of lime mortars toward water and water vapor. For instance, enhancement of lime mortars in terms of hydric properties were almost always concluded when oils were added in the mixes, in both historical solutions and modern studies [9; 10; 11]. A recent study reports that the unsaturation level of additive fatty acids is a key parameter in success for lime mortars' hydrophobization [12]. However, many studies concentrated on the mortars cured in laboratory conditions, while increment of climatic parameters in in-situ conditions might occur considerable alterations in the results. The mortars of this study are aimed at exploring possibilities for in-situ applications in the Pasargadae and Persepolis world heritage sites (Fars province, Iran), where a great need for various types of interventions with sustainable and economic restorative mortars is reported [13]. Restoration activities in the developing countries with numerous cultural heritage sites is highly dependent on economy of conservation [14]. Added to the environmental aspects, economically feasible material solutions can broaden the conservationdomain potentials [15; 16; 17]. Moreover, one of the principles of the ancient Persian architecture had been dependency on the materials from the site surroundings. For example, stone construction of Pasargadae and Perseopolis had been dependent in terms of materials on the existing mines of the zone. The authentic construction was carried out without mortar joints. Nevertheless, due to degradation, the created gaps need to be filled with compatible mortars in order to hinder adverse environmental threats (Figure 1). In this study, aiming at respecting the essence of the historic methods, the mix-design was decided to be dependent on the site potentials (i.e., local lime, sand, and stone powders). Independent reproducibility of restorative mortars and availability of their components are crucial in historical developing countries. The mix-design of the current study has been delivered from previous studies and has been characterized and showed considerable enhancements in a recent study under laboratory conditions [12]. However, realizing the efficiency of the mix-design in the in-situ conditions requires a verification of the mix with local materials and at the actual in-situ climatic curing conditions. The following research assesses the lime mortars with local components in presence of two types of fatty additives (sesame and spent sesame cooking oil), in laboratory and the in-situ conditions of the designated historical site (in Fars province, Iran), simultaneously. The first aim was to assess if the probable improvement of hydric properties of lime mortars in presence of fatty acids can occur in realistic in-situ conditions with more climatic parameters compared to the laboratory. In-situ conditions can substantially affect the curing process due to climatic parameters such as air flow and daily thermal variations. The second aim was to verify if the potential hydrophobization of the mortars in the presence of the organic additives used in this study confirms the effect of their unsaturation level discussed in previous research [12].