Fernando Vegas López-Manzanares

The ancient gypsum mortars of the historical façades in the city center of Valencia (Spain)

In the historical centre of Valencia (Spain), the brick facades of the residential buildings which were built or modified in the end of the XVIII th century and the beginning of the XX th century have been protected and decorated with continuous renderings. According to the constructive tradition, the renderings had to be made with lime mortars, but the recent studies allowed to know their real nature: they are gypsum mortars. The main aim of the study has been to know the nature and the technical aspects of the historical renderings of the facades of the centre of Valencia, in order to discover their secrets from a theoretical and experimental point of view. Therefore, together with the examination of bibliographical sources, several samples of the historical mortars have been collected from renderings. The analytical results confirm that the great majority of samples are composed by gypsum mortars, with different degrees of purity and a variable amount of aggregate and lime. Some samples are mixed mortars (gypsum and lime mortars), but there are also examples of pure lime mortars probably indicating a change in the constructive tradition of the city in a historical moment as testified by the presence of buildings with brick walls bonded with lime mortar and gypsum mortars in the rendering. This fact supposes a conscious application of the gypsum in exteriors and the existence of a specific ancient technique. Moreover the analysis of the surfaces of renderings characterized by a specific finishing and several layers of painting, allows us to confirm that organic substances have been applied in order to protect the gypsum mortars from the inclemency of the weather. Definitively, the characterization of the gypsum mortars that cover the historical facades of the centre of Valencia allowed us to discover a particular and distinguishing aspect of the constructive tradition of the city that must be protected and valued in order to achieve its preservation.

Microwaves as a Remedial Treatment of Wood

A pilot experiment of microwave treatment was carried out on an Art Nouveau residential building erected at the beginning of the 20th century in Valencia, Spain. The timber structure was affected by a combined damage caused by Anobium punctatum (common furniture beetle or common house borer) and Kalotermes flavicollis (yellownecked dry-wood termite). After performing an exhaustive preliminary study on the building and analyzing the different alternatives of wood treatment, it was decided to use a microwave machine especially designed to eliminate this type of wood boring insects.This machine generates microwaves, a type of electromagnetic radiation, with a frequency of 2.45 GHz. This circumstance makes it possible to produce a high-frequency alternating electric field that causes the rotation of the molecular dipoles of water. Because of this continuous rotation the temperature of the water rises considerably.By heating up the humidity inside a living being, as in the case of xylophagous insects, an artificial fever in the body is generated, and since the animal is not capable of tolerating this temperature, it dies.In order to eliminate xylophagous insects, the wood moisture content (usually between 10% and 12%) and the presence of water in wood boring insects (around 90%) must be taken into account. Due to the greater content of humidity the increase of the temperature is higher and quicker in insects than wood.After having studied and experimented with different combination of power and time of exposition to the microwaves, this machine was found capable of eliminating any type of insect that may live inside the timber without harming the wood itself.Prior to this pilot intervention, several research works were carried out with the same microwave machine, both on structural timber and wooden works of art. In all these studies it was observed that no damage was caused either to the wood or to the finish of the works of art including pigments, polishes, stains etc. On the other hand, 100% efficacy was achieved in the elimination of xylophagous insects.This article describes the design, experimentation and perfecting process of this microwave machine and its pilot application on structural timber in an Art Nouveau residential building. As an example of method, the intervention followed the main steps of diagnosis and treatment testing including the analysis of several options of intensity and time that led to the positive final results obtained.

Understanding Spanish Timber Jack Arch Floors: Examples of Assessment and Conservation Issues

Jack arch floors are structures made of timber joists, with round or squared section, and segmental vaults either made of flat tiles or poured plaster conglomerate. They are especially diffused along the Mediterranean coast of Spain and can be considered as a main feature of the historical and vernacular architecture of the area. In order to assess and grade these structures several Spanish standards have been considered; however, even if the information contained is useful the Italian standard for the on-site diagnosis UNI 11119 of 2004 has been preferred. The method described in this standard leads the assessment through the grading of each and every timber element and the assignation of bearing properties that are essential for the consolidation project. This article will expose three examples of jack arch floors of the Valencian Community graded using the Italian standard and the conservation issues that arise from the results.

A Peculiar Spanish Timber Floor, the "Revoltón": A Diagnostic Example at the "Palacio del Marqués de Benicarló"

The paper deals with the application of the Italian method for assessing on-site and diagnosing timber elements to a distinctive Spanish type of horizontal structure called “revoltón” i.e. jack arch floor. As in Spain does not exist a specific regulation for the on-site diagnosis of timber elements, this analysis was performed according to the Italian standard UNI 11119. Due to the peculiar features of the jack arch floor some modifications were applied to the method.During spring 2012 the authors had the opportunity to carry out a pilot project by making a diagnostic analysis on a whole three stories building. The building, “Palacio del Marqués de Benicarló”, located in Spain in the town of Benicarló, between Barcelona and Valencia, was erected during the second half of the XVIII century. It maintains the original internal distribution and structure, and it is characterized by precious ceramic decorations on walls and floors. All the horizontal structures studied inside the palace were jack arch floor except the roof structure that was also made of timber.The results of the project described in the paper clarify the specific problems of the horizontal structures and the roof surveyed during the fieldwork. These results are accompanied by several plans that represent the information recovered on-site and lead to a complete assessment of the structures. The plans include the grading based on wood defects, the local moisture content of wood, the superficial and inner decay due to insects and rot and the deformation of the joists. In this way it was possible to locate the areas of the palace where more problems were concentrated, and better understand the causes and origin of the damages.

EDUCATIONAL INNOVATION PROJECT AT UPV (SPAIN): “WITH YOUR HANDS. EARTH AS A MATERIAL FOR DEVELOPING CREATIVE AND CONSTRUCTIVE SKILLS”

This text presents a project for educational innovation and improvement in the field of architectural restoration carried out at the School of Architecture of Universitat Politècnica de València (UPV, Spain). The project was carried out in the 2016-2017 academic year. The Iberian Peninsula is a territory that is extremely rich in earthen architecture, both monumental and non monumental. The size of the territory and its heterogeneous geography and climate, its cultural diversity and the different materials available are the main factors which generated a wide range of earthen construction techniques throughout history (rammed earth, adobe, half-timber, cob and its variants). This heritage is a major part of the local culture both because of its remote origins and the varied technology adapted to natural and cultural surroundings. In addition, given its salubriousness and its cultural relationship with the habitat, earthen architecture is currently an interesting line in the construction of new architecture as earth is the most sustainable material, providing energy saving throughout the entire construction process. However, this material is barely studied at university, and newly qualified architects have very little training in this field. The main aim of this project was to bring earthen architecture closer to students in practical terms through active learning methods. The aim of this project for educational innovation and improvement is to introduce earth experimentally as a construction material in three subjects at the School of Architecture (Architectural restoration, a compulsory subject in fifth year; Composition, a compulsory subject in fourth year; and Restoration of non monumental historic architecture, an elective subject from the Master’s in Architecture) through group and individual activities aimed at students taking part. These activities were proposed with a “learning by doing” methodology so that students could learn about the material while working and experimenting with it.]

WORKSHOP ON TRADITIONAL ARCHITECTURE. EXPERIENCE INDIA-SPAIN AT UPV CAMPUS

Traditional architecture is closely linked to the territory it is found in. However, in some instances it is also possible to find similarities and points in common between constructive techniques that are very far apart in terms of location. This text presents a teaching experience where the main aim was to bring into contact two constructive realities connected with the tradition of earthen construction and tiled vaulting. The contemporary world is comprehensive and global, and links between students must also be so. Therefore, it is necessary to encourage multicultural reunions where students can further their knowledge of a given topic. In this context, an experimental workshop was carried out in July 2017 at the campus of Universitat Politècnica de València (UPV) with the participation of students from the SAL School of Architecture in Ahmedabad and the Higher Technical School of Architecture of Valencia. This workshop allowed students to work with distant constructive traditions that were similar to their own and this exchange allowed them to broaden their knowledge. This experience also showed the Indian students how conservation, assessment and restoration work is carried out on local heritage, extremely important now that the city of Ahmedabad has been chosen as a UNESCO World Heritage Site.

CULTURAL VALUES OF EARTHEN ARCHITECTURE FOR THE SOCIETY OF THE FUTURE. WORKSHOPS FOR CHILDREN AT THE SUMMER SCHOOL OF THE UPV

Vernacular architecture heritage, both local and global, is one of the mainstays of cultural structure. This heritage is currently in a state of disrepair and abandonment, resulting mostly from a lack of awareness and good judgement on the part of the people. Therefore, one of the key actions for the promotion of proper assessment is education on cultural, social and environmental values. Educating the society of the future, our children and youth, is the key to success in this cultural recovery process. Earthen architecture in particular is unknown to many and forgotten by others. However, it represents the history, the present, and the future of many different cultures. At times, this architecture is considered to be poor, uncatalogued and worthless. We have taken on the task of changing this perception, promoting this building technique and working towards earthen architectural heritage being recognised as part of our constructive knowledge. This article presents the activities and workshops on earthen architecture held for children aged eleven and twelve at the summer school of the Polytechnic University of Valencia (UPV) in July 2015. The content of the workshop was divided into four training blocks: earth, adobe, earthen architecture and adobe construction. Activities were divided into two sessions lasting an hour and a half each. The first two blocks were included in the first session while the last two were left for the second. Approximately two hundred students, organised into eight groups of twenty-five children each, took part in these activities. The block dealing with earth as a material was the most theoretical in the activity. It allowed children to understand the properties of earth and its characteristics and to support this through their own experience. In the section studying adobe, children worked on the construction technique of adobe, by making their own raw earth bricks. When studying earthen architecture, students learnt about other cultures and different geographical realities. In addition, students were generally able to identify earthen architectural heritage. Finally, by working on the block on construction with adobe, skills in the technique were improved. At the end of the session, students built a wall using their handmade bricks. This encouraged teamwork and an overall sense of belonging within the group. During the activities, quotes from students included statements such as “We do not have to underestimate this architecture, even though it looks dirty and worthless. It requires hard work and many people have been involved”. This shows how the workshops made these young students aware of this architecture, an architecture which respects the environment and promotes camaraderie and creative work.