Adaptive Reuse (AR) of heritage buildings is a sustainable approach to preserving cultural heritage while accommodating new functions. Despite the growing importance of AR in the last decades, a lack of comprehensive models for AR, particularly concerning heritage buildings, persists. This research addresses this gap by developing a model that guides architects in the AR process, drawing on international literature and Dutch AR practices, with a focus on its adaptation and possible application in the Iranian context.
A systematic review of the literature revealed a lack of overarching models for AR, and led to the development of a conceptual model. This model includes 10 steps, which are: “initiative”, “analysis of the building and its surroundings”, “value assessment”, “mapping the level of significance”, “adaptive reuse potential (function)”, “defining the design strategy”, “final decision-making”, “execution”, “aftercare and maintenance”, and “evaluation after years”. In addition, based on the analysis of 48 award-winning AR projects in the Netherlands and Europe, six key criteria for effectiveness were identified: sublimation-architectural aspects, sublimation-cultural aspects, social value creation, environmental sustainability, economic value creation, and innovation aspects.
Testing the initial model in the Dutch context, led to further development into the EARHB model, enriched with methods and tools used by the architect in the different steps of the AR process. In this dissertation, the EARHB model, including its methods and tools, is referred to as the EARHB framework.
Research on Iranian AR projects and interviews with architects demonstrate the EARHB framework’s potential, confirming that some of its process steps, methods, and tools are in use. Some limitations, due to cultural, regulatory, and practical constraints, might affect full implementation of the framework in Iran. Nevertheless, the potentialities of the proposed EARHB framework, offering a comprehensive and adaptable approach for enhancing the effectiveness of AR projects in different context worldwide, are confirmed.@en

Repeated crystallisation of salts in the pores of building materials is a common cause of damage in buildings. Sodium chloride (NaCl) is one of the most common salts, responsible for weathering in the built environment. Mortars, especially when used as plasters and renders on the surface of walls, experience fast degradation as they are exposed to conditions perfectly conducive to salt weathering. As a consequence, their service life is often compromised, requiring frequent replacements. Costs associated with replacement interventions have a high economic and a social impact. Over the last two decades, the use of crystallisation inhibitors as an additive to prevent/mitigate salt crystallisation damage in building materials has shown promising results. Sodium ferrocyanide (NaFeCN), a crystallisation inhibitor of NaCl is particularly effective in preventing damage by inhibiting/delaying NaCl nucleation and altering NaCl’s crystal habit. When mixed-in air lime-based mortars, NaFeCN has been shown to considerably improve the salt weathering resistance....@en

Bioreceptivity is a natural phenomenon that has been observed on building material for many years. Bioreceptivity is when materials are being colonized by one or more species of living organisms without necessarily going under biodeterioration. (Guillitte, 1995) Based on the literature, bioreceptivity depends on three main factors: on climatic conditions, the topology of the colonized element and the material.
By considering these variables, this research focuses on engineering a workflow capable of supporting bioreceptivity-oriented design. More specifically, it investigates how computational performance analysis and optimization can support the integration of bioreceptive materials in customizable building elements, which could be produced by digital fabrication.
For research purposes, the research is split in two main parts which run in parallel. This research takes as a case study mosses, which generally cannot withstand high solar radiation and are dependent on water for their survival and reproduction.
The first part, investigates on a digital model, how surface topology modifications could improve bioreceptivity by reducing the solar radiation of a surface while directing water over them. This is approached by a script which examines through a case study, to what extent the solar radiation of a surface topology could be reduced through topological modifications and which factors influence it. Even if the average solar radiation of the case study was significantly reduced through an optimization process, it is not clear to what degree topology can contribute to the improvement of bioreceptivity because this fact can only be validated physically.
The second part, focuses on lime-based mortars and examines how their composition can affect bioreceptivity. Based on the literature, material properties like high water capacity, high water retention, permeability and high total porosity can benefit bioreceptivity. Four different lime-based mortars were tested, through laboratory experiments, seeking the relation between their water transport behavior and bioreceptivity. Grain size distribution in combination with binder to aggregate ratio are the main factors which influence mortars’ transport behavior. In order to observe the relation between their water transport behavior and bioreceptivity, a moss growth experiment was conducted in a controlled environment. The short timeframe of the experiment makes it difficult to draw definitive conclusions.
The methodology that was developed in these two parts, is finally attempted to be combined in a bioreceptivity-oriented design approach in order to express a new architectural vocabulary. Through a research-by-design approach, three design approaches are conceptualized, compared and prototyped, raising the potential of bioreceptive applications.

The current study focuses on the development of a new façade system which introduces greenery as part of brick walls. The main aspects of the proposed system are sustainability, moisture and materials, water supply and structure stability. The goal is to achieve a balanced relation among these aspects and reflect those into the product design. The current report consists of design and experimental research, aiming to explore the potential and tackle the challenges of designing a complete façade system. By identifying existing experimental and design research in relevant literature, a new green façade product is proposed. The stability of the system is based on a non-mortar solution, utilizing the Drystack® elements for the wall assembling. The design phases led to the integration of the system components, focusing on the use of a passive irrigation system. This is further analyzed with a building case study for better understanding its functionality and manufacturability. The different elements constituting the system, drystack, greenery, soil substrate and irrigation, are then decided based on theoretical research. Finally, experimental work is conducted in order to validate the project decisions and propose further improvements.

In the last few decades, air pollution constitutes a major global problem that results in adverse effects on human’s health, nature and the built environment. Many abatement strategies have been adopted for its combat in all these different fields. This graduation project focuses on the built environment and tackles the application of TiO2 on facades of existing buildings with historical significance in the city of Athens. TiO2 is a promising photocatalytic material, capable of neutralizing air pollutants via the mechanism of photocatalysis and under certain environmental conditions. Its use aims at a wider application in urban landscapes, in order to alleviate the air pollution levels. This widespread application can be achieved by the creation of 3 different TiO2 application levels that can be applied on the different facade components. The choice of application is realized mainly via the assessment of their NOx efficiency, the assessment of values employed in the field of conservation as well as their effect on cost. This evaluation takes place through a number of steps that a designer can follow for the selection of the suitable level as well as for the components that can eventually be modified.

In the current thesis, this set of steps/roadmap is presented and validated with the help of an actual case study, where the balconies are the main chosen facade element undergoing alterations of the 2nd level. It goes without saying that the flow can be followed and applied for different components, different buildings or even in different cities and locations. Athens is simply a representative example for this cause. Since the main goal of the project is the optimum performance of TiO2, a series of different balcony panels are designed via the manipulation of surface area and roughness, two very crucial factors for the successful activation of photocatalysis and pollutant neutralization. The panels undergo 3 different analyses: radiation, wind and NOx removal with a successive evaluation, resulting in one ideal geometry, whose NOx levels are compared to those prior to its implementation and those of the 1st application level.

The final part of the graduation project focuses on the results yielded by these different analyses and the conclusions that are pointed out and could prove pivotal for a designer. After the application of the panels to the chosen street canyon, the evaluation of the NOx abatement efficiency, the value and cost of each tested scenario, results indicate that the 2nd application level of TiO2 is more efficient than the 1st in terms of NOx removal efficiency. Nevertheless, a combination of both levels could considerably balance all 3 criteria, namely the aspect of NOx removal, values and cost.

Keywords: Urban Facades I Air Pollution I TiO2 I Air Purification I Historical Significance

The preservation and restoration of intricate stucco ornaments, which are part of our collect cultural Heritage, is under threat due to a diminishing number of skilled restoration plasterers. The highly physically demanding- and labour intensive nature of this work makes it unsustainable for the human body and advocates for a more sustainable alternative restoration method for the future. Digital Fabrication has the potential to offer such an alternative method. While 3D scanning, digital repair and 3D printing are all proven technologies, stucco ornament restoration often requires an on site fabrication solution directly onto a ceiling or wall due to the brittle nature of prefab stucco elements. The research explores how an in-situ 3D printing technique can be developed for the restoration of stucco ornaments by focussing on three main topics: 1) developing gypsum-based 3D printing materials, which are compatible to gypsum ceilings and comply with criteria for extrusion based 3D printing; 2) Designing and prototyping 3D printing tools including an extruder and material delivery system; 3) Conceptualizing a Restoration Robot Platform with which the developed printing material can be used with the developed 3D printing tools, for on site stucco ornament restoration. The insights gained from the development of the printing material and printing process are integrated into digital fabrication software used in practise, through a proposed plug-in and workflow.

Damage due to the crystallization of salts is a common problem in porous building materials. Also mortars used in the restoration of historic buildings are often subjected to a high salt load, resulting in a rapid degradation and high maintenance costs. Especially lime-based mortars, used for example as render, plaster, bedding mortar or pointing mortar, are vulnerable to this type of damage. Despite the extensive research efforts, no definitive solution yet exists to tackle the problem of salt decay in building materials. Existing solutions to improve mortar resistance with respect to salt decay such as modifying the moisture transport properties of the mortar (e.g. plaster with water-repellent properties) or increasing its mechanical strength of the plaster mortar (e.g. by using a different binder such as cement), often show compatibility problems and might cause even more damage to the to be restored (historic) fabric. Recently a new approach, based on the use of crystallization modifiers to alter the salt crystallization process, has been proposed. The aim of modifiers is to prevent or mitigate salt crystallization damage in building materials. Modifiers are ions or molecules that can keep the salts longer in solution (inhibitors), facilitate the precipitation of a certain crystal phase (promoters) and/or change the shape and size of the grown crystals (habit modifiers). These effects are often present in combination, i.e. a promoter or inhibitor can at the same time act as habit modifier. @en

Nanolimes, i.e. dispersions of lime (Ca(OH)2)nanoparticles in alcohol, have been extensively investigated over the last two decades as consolidation products for calcareous substrates.
The use of nanolimes for consolidation of mural paintings arises from the lack of e ective and compatible consolidants for this type of substrates; the use of nanolimes was later extended also to limestone and lime-based mortars, as an alternative for silica-precursor consolidants (e.g. tetraethoxysilan - TEOS), which had shown to have a limited e ectiveness and compatibility with calcareous substrates.
Nanolime dispersions are characterized by a very small size of the lime particles, which should provide a proper penetration within the porous network of most building materials. In fact, a homogeneous and in-depth penetration of the consolidant is a crucial requirement when dealing with decayed stones and plasters/renders.
The e ectiveness of nanolime dispersions reported in literature appears controversial. Some authors observed a proper penetration and moderate consolidating action, whereas others report poor penetration, poor consolidation action and sometimes the formation of a white haze on the treated surface. There is no agreement concerning the factors a ecting the transport and deposition of the lime nanoparticles within a porous network, and the causes of the observed drawbacks are not well understood.
Therefore, the main research question is:

Is nanolime a suitable alternative to silica-precursor consolidants (e.g. TEOS) for the consolidation of calcareous substrates?

More speci cally, the following research questions can be formulated:

– How and up to which extent can the e ectiveness and compatibility of nanolime be improved? How can deposition of nanolime in depth be improved and the appearance of a white haze on the surface avoided?
– How can nanolime properties be ne-tuned to improve the e ectiveness and compatibility of the treatment?
– What is the e ect of di erent application methods on the e ectiveness of nanolime consolidation?

This research investigates and elucidates the behaviour of nanolime products for consolidation of calcareous substrates. Based on the developed knowledge, it proposes and validates a methodology (including solvent modi cation and application protocol) for improving the consolidation e ectiveness of nanolime dispersions, making these a suitable alternative for TEOS products.
Firstly, an experimental campaign was carried out in order to understand the penetration and deposition of commercial nanolimes on coarse porous calcareous substrates (Maastricht limestone). The main cause of the poor nanolime deposition in-depth was identi ed in the back-transport of the nanoparticles towards the drying surface, as a consequence of the high volatility and low kinetic stability of the dispersions.
The modi cation of the nanolime properties, through the optimization of the solvent, appears thus a feasible strategy to improve the in-depth deposition of the lime nanoparticles. New nanolimes were synthetized and dispersed in a selection of solvents conferring di erent stability and drying rate to the obtained nanolime dispersions. A conceptual model, correlating the properties (i.e. drying rate and kinetic stability) of nanolimes dispersed in di erent solvents, to the moisture transport behaviour of the substrates to be treated, was conceived. The model was experimentally validated on coarse porous (Maastricht) and ne-porous (Migné) limestones.
Experimental results con rmed the predictions of the model that nanolimes dispersed in solvent with lower volatility and stability (e.g. water or butanol) have a good in-depth deposition within coarse porous networks. On the other hand, solvents with higher volatility and guaranteeing higher kinetic stability (e.g. ethanol or isopropanol) to the relative dispersions, should be preferred for substrates with ne porous networks. Fine- tuning the properties of the nanolime dispersion (by modi cation of the solvent) to the moisture transport behaviour of the substrate, is shown to be a successful strategy for improving in-depth deposition of lime nanoparticles.
On the basis of the obtained results, the solvent mixture was further ne-tuned using ethanol-water mixtures. Results proved that ethanol-based nanolime, mixed with a minor amount of water (5%), can provide be er nanoparticles in-depth deposition within coarse porous substrates (e.g. Maastricht limestone), when compared to dispersions in pure ethanol.
The application procedure of nanolime dispersions was also studied and optimized, this step being a crucial aspect for a successful consolidation; nanolimes were applied both by capillary absorption (method commonly used for laboratory tests) or by nebulization (method widely used in situ) on a coarse porous limestone and a mortar.
20 Nanostructured lime-based materials for the conservation of calcareous
The research showed that results obtained by application through capillary absorption do not always correspond to those obtained by nebulization.
The e ectiveness and compatibility of nanolimes with improved properties and a ne-tuned application protocol were nally veri ed. Fresh and weathered Maastricht limestone, as well as lime-based mortars, were treated. Results showed that nanolime dispersions can guarantee an in-depth consolidation both in laboratory mortar specimens and weathered limestone, with only a moderate alteration of the total porosity and of the moisture transport properties of the investigated substrates.
Therefore, nanolime dispersions, provided that they are properly formulated and applied, can be a suitable and compatible alternative to TEOS for the consolidation of coarse porous substrates.
This dissertation contributes to de ne guidelines to support restorers and professionals in the choice and application of nanolime dispersions for consolidation of calcareous substrates.@en