

\chapter{Methodology for Designing examined box}
\label{ch:Methodology_B}

In this chapter we introduce how to design the examined box with parametric method. The design mission is split in parts:

\begin{itemize}
	\setlength{\itemsep}{1pt}
	\setlength{\parskip}{0pt}
	\setlength{\parsep}{0pt}
	
	\item Opaque structures
	\begin{itemize}
		\setlength{\itemsep}{1pt}
		\setlength{\parskip}{0pt}
		\setlength{\parsep}{0pt}
	
		\item  Wall
		\item  Roof
		\item  Floor
	\end{itemize}
	\item Transparent structures
	\begin{itemize}
		\setlength{\itemsep}{1pt}
		\setlength{\parskip}{0pt}
		\setlength{\parsep}{0pt}
		
		\item  Window glazing
		\item  Window frame
		\item  Window attachment
	\end{itemize}
	\item Operational schedule
	\begin{itemize}
		\setlength{\itemsep}{1pt}
		\setlength{\parskip}{0pt}
		\setlength{\parsep}{0pt}
	
		\item  HVAC schedule
		\item  CNV schedule
		\item  Dimmer control
\end{itemize}
	
\end{itemize}
And our introduction follow this process.

\section{Design Object: "Hardware" and "Software"}
\label{sec:design-object}

The concepts of \textit{bionics} or \textit{biologically inspired engineering} involve drawing inspiration from nature's wealth of experience. Rather than merely imitating the physical forms of creatures, we aim to extract the underlying philosophy. Our planet, through billions of years of evolution, has offered us a multitude of life forms. These life forms are not just organisms; they also represent solutions that can adapt to their environments. In the animal kingdom, natural forms shape not only physical structures but also behavior.

Buildings, too, need to exhibit behavior and adapt to increasingly severe extreme weather conditions. They cannot rely on fixed operational templates; instead, they should be capable of adaptation and evolution.

Our goal is to optimize both the physical form and the operational behavior of buildings, similar to designing "hardware" and "software." What makes a machine powerful? It's the combination of both hardware and software. What makes a species competitive? It's the interplay of body and behavior. In the context of building design, what makes a building efficient? It's the synergy between equipment and operation.

To enhance efficiency, we intend to design both the building's physical form and its operational program. These components are categorized as \textbf{static} design and \textbf{operative} design. Conventionally, in our pursuit of exceptional indoor environments, we have relied on passive and dynamic design methods, distinguished primarily by their energy consumption. However, this time, we adopt the analogy of "Hardware and Software." This approach involves classifying the design into two different categories: \textbf{Static} and \textbf{Operative}. The primary distinction lies in whether the designed functionalities can be controlled or turned off.




\section{Proposal for Retrofitting: Static Design}
\label{sec:static-design}

Static design plays a fundamental role in sustainable architecture, and this time we approach it with a biological analogy.

Imagine your room as a living organism, akin to a playful dog. Just as a dog's furry coat provides protection, the shading elements in a room serve a similar purpose. Thoughtful planning and the use of appropriate shading materials keep the room cool in summer and warm in winter, much like a dog's fur.

Now, consider the room's outer layer as its skin. A healthy dog with smooth skin efficiently regulates its body temperature. Similarly, an excellent room envelope design optimizes energy exchange between the interior and exterior, ensuring a stable indoor temperature and reducing energy waste.

Our mission is to make the room self-sufficient, reducing its reliance on external resources. By incorporating shading elements (akin to fur) and designing an efficient room envelope (akin to skin), we ensure year-round comfort while reducing dependency on conventional energy sources. This approach promotes environmental friendliness and sustainability.

In this case, we focus on two main elements of passive design: the opaque and transparent envelope, which are basic components in modern architecture.

\subsection{Opaque Envelope}
When designing the opaque envelope, several aspects require attention:

\begin{itemize}

    \item \textbf{Insulation:} Adding high-quality insulation to the walls, roof, and floors minimizes heat transfer, enhancing interior comfort and reducing the need for heating and cooling.
    \item \textbf{Thermal Mass:} Incorporating ``materials with high thermal mass, such as concrete or stone, in the opaque facade can absorb and store heat during the day and release it at night,''\cite{Ugreen} contributing to temperature stability.
    \item \textbf{Airtightness:} Ensuring airtight construction prevents air leakage.
    \item \textbf{Thermal Bridge Mitigation:} Addressing thermal bridges in the building envelope helps eliminate localized areas of increased heat transfer.
    \item \textbf{\glsxtrfull{PCM}:} The introduction of \glsxtrshort{PCM}s into the opaque facade can store and release energy during phase transitions, contributing to temperature regulation.
\end{itemize}


We focus on insulation and thermal mass, as they are the most common methods. Airtightness and thermal bridge mitigation are highly related to the construction method, with limited impact on the entire room. \glsxtrshort{PCM}s represent an exciting future direction due to their ability to influence both temperature and transparency, making them crucial for light and form considerations.

~\\
Our idea is to add a new insulation layer to the existing wall, allowing the original wall volume to serve as a thermal mass. This approach is universally applicable to modern buildings, with facade strength being the primary concern. However, our insulation panels are relatively lightweight, and any retrofitting proposals must account for their load-bearing capacity.



\begin{table}
\centering
\label{ch:PriceInsulation}
  \begin{threeparttable}
    \caption{Insulation price}
     \begin{tabular}{|ccccccc|}
        \toprule
     &   & Wall & Roof & Floor & &\\
        \midrule
    &  &   180        & 180    & 200  &  &   \\
        \bottomrule
     \end{tabular}
    \begin{tablenotes}
      \small
      \item  The unit of the numbers are euro per cubic meter.
    \end{tablenotes}
  \end{threeparttable}
\end{table}



\begin{table}[h]
\centering
\includegraphics[width=\linewidth]{images/tables/tabular/Insulation_Roof.png}
\caption{Construction of roof} 
\label{tb:Construction of roof}
\end{table}
\begin{table}[h]
\centering
\includegraphics[width=\linewidth]{images/tables/tabular/Insulation_Wall.png}
\caption{Construction of wall} 
\label{tb:Construction of wall}
\end{table}
\begin{table}[h]
\centering
\includegraphics[width=\linewidth]{images/tables/tabular/Insulation_Floor.png}
\caption{Construction of floor} 
\label{tb:Construction of floor}
\end{table}

\paragraph{Pricing}
I assume that a simple attachment method can be used for the panels, which applies to all selected proposals. I use an assumed cost of 2000 euros to represent this attachment method.
Since our construction method remains constant, our goal is to investigate the optimal thickness of the insulation. In other words, thickness is the only variable for opaque design. And the thickness affects the final price for the insulation. The database here is built by refering to the real-time suppliers' website. With their product tabular\cite{Knauf}, we choose \textit{Knauf}, and we also consider the general retrofitting case in Italy \cite{Lollini2006}. And we simplify the price into integer values. See \cref{ch:PriceInsulation}.


\subsection{Transparent Envelope}
When designing the transparent envelope, we consider several aspects:

\begin{itemize}
\setlength{\itemsep}{1pt}
\setlength{\parskip}{0pt}
\setlength{\parsep}{0pt}

    \item \textbf{\glsxtrshort{Low-E} Coatings.} \footnote{Applying \glsxtrfull{Low-E} coatings to glazing reduces heat transfer and helps control solar heat gain.}  
    \item \textbf{Double or Triple Glazing.}
    \item \textbf{Solar Control Films.}
    \item \textbf{Operable Windows.}

\end{itemize}





To facilitate this, I have designed six types of glazing using the acg configurator website. These types vary in cost and \glsxtrshort{U-value}, with three being double glazing and three being triple glazing. The choice of window frame remains consistent, based on sistema secco's products.

Glazing systems are complex and difficult to parameterize due to their highly compact nature. A linear function cannot easily describe the performance and input parameters of a window system. To address this, I have categorized the glazing types based on their \glsxtrshort{U-value}s, assigning them serial numbers from 0 to 5, where higher numbers correspond to higher \glsxtrshort{U-value}s.

In practice, the algorithm requires a wider domain than the range from 0 to 5, so a division trick\footnote{the real variable is defined in 0 $-$ 50, then divided integrally by 10, so the outcome seems a variable from 0 to 5.} is applied to accommodate this. As the integer increases, the \glsxtrshort{U-value} output steps up non-smoothly, reflecting the challenge in customizing window systems.

\begin{table}[h]
\centering
\includegraphics[width=\linewidth]{images/tables/tabular/GlazingType.png}
\caption{Glazing types of the window} 
\label{tb:glazingType}
\end{table}


\paragraph{Pricing}
The cost of window systems, representing both the glazing and framework, is a complex issue. The supply chain involves multiple links, with each affecting the final price. Installation costs also vary based on factors such as the environment, height from the ground, and the type of external wall.

However, I have obtained reference costs from several sources, providing a reasonably persuasive range. Similar to the approach used for \glsxtrshort{U-value}s, I manually assigned costs to each type, following the principle that higher cost correlates with better performance. The costs fall within the range of 250 to 600 euros per square meter.

In summary, I have created an idealized supplier that offers a variety of products at a constant price, following the principle of "higher cost for lower \glsxtrshort{U-value}." While this simplification methodology sacrifices some authenticity, it retains the core logic of the experiment. It's important to note that in actual projects, real suppliers can provide product data, allowing for the immediate application of the same logic to obtain optimized results.

\subsection{Shading Device}
The shading device, in contrast to the fur and skin of the building, is not equally fundamental. In this context, we utilize fixed louver shading. This approach is practical and aligns with our research goals. Our objective is to strike a balance between multiple goals, and we anticipate scenarios where trade-offs exist. Fixed louvers enable us to explore such trade-offs effectively.

While dynamic devices could be used, their fixed cost makes it a single-goal problem. For fixed louvers, we can focus on the quantity of louvers, which directly affects the cost. By varying the number of louvers, we can adjust the shading coverage from top to bottom. The challenge is to determine the required shading area and its associated cost. The use of \textit{division trick}\footnote{the real variable is defined in 0 $-$ 50, then divided integrally by 5, so the outcome seems a variable from 0 to 9.} helps address this issue.

In addition to louvers, I have included an enclosed extrusion border shading with a depth of 0.2 meters.

\paragraph{Pricing}
The pricing for shading devices follows a straightforward rule: the more louvers, the higher the cost. Although this section has its weaknesses, it has a relatively minor impact on the simulation. Additionally, shading devices are typically more cost-effective. If a designer has a budget of 1000 euros to complete the envelope, they would likely allocate around 900 euros for windows and 100 euros for shading, if required. I assumed that the basic framework for each shading system costs 20 euros, and the louvers are priced at 2 euros per meter.


\section{Proposal for Retrofitting: Operative Design}
\label{sec:Operative-design}
\subsection{Brief Introduction \& Classification of Operative Design}

The operative elements are those capable of automatically changing their functioning condition and can be subdivided into two classes: high power and low power. The former, like \glsxtrshort{HVAC} systems, consume a significant amount of power when operating, while the latter, such as \glsxtrshort{CNV}, requires minimal power for opening and closing windows. The high power elements are usually integrated with control systems, while the low power elements are typically static components with added controls, such as manual windows with openers.

The realm of lighting occupies an interesting position, serving as an intermediate term between the two. In this project, we also develop a more intelligent lighting system.

Drawing parallels with the analogy of a dog's primary and smaller muscles, we can think of:

\begin{itemize}
    \item High-Energy Operative Design is akin to a dog needing vigorous physical activity, such as running or playing. In architecture, this involves using \glsxtrshort{HVAC} systems, much like a dog regulates heat through panting and sweating, actively to adjust temperature and ventilation.
    \item Low-Energy Operative Design is comparable to controlling the dog's state to keep it calm or alert. In architecture, this involves intelligent control systems that adjust indoor temperature and lighting through natural ventilation and daylight. Just as a dog's fur can raise to regulate its temperature, building shading devices can automatically adjust to keep the interior cool.
\end{itemize}

The goal of operative design is to ensure optimal thermal conditions indoors, much like ensuring the comfort and state of a small dog. Through intelligent control systems, natural ventilation, and shading devices, we can maintain comfort, reduce energy consumption, and provide occupants with a pleasant living environment.

\subsection{\glsxtrshort{HVAC} System}

To simulate the \glsxtrshort{HVAC} system, I have chosen the All-air \glsxtrshort{HVAC}, which can condition and deliver the necessary volume of air. Specifically, I selected \glsxtrshort{PVAV} with a gas boiler reheat. This choice allows for comparisons between different weather zones, making it a reasonable selection, even though I don't necessarily transfer the system among different regions.

I have maintained other parameters as default settings, representing various conditions. Due to constraints from \glsxtrshort{HB}, I didn't explore this aspect in depth. However, for those interested in optimizing the \glsxtrshort{HVAC} system itself, the Ironbug component series from \glsxtrshort{LBT} can be used to obtain more detailed results.

\paragraph{Pricing}
The energy consumption cost electricity power, which finally cost currency as well. The price is assumed to 95 euro per kWh\cite{EnergyPrice}, which's accessed in the summer of 2023. Notably, due to not only the political issue, the energy price is fluctuating at the time. However, since we use the same price for all the cities, this factor just affects on the absolute value of the cost FV, it doesn't make difference in the relative ranking of each solution.
,,,,,,,,,,



\subsection{Controlled Natural Ventilation}
\label{Controlled Natural Ventilation}
Natural ventilation, also recognized as comfort-ventilation\cite{79}, stands as a fundamental passive cooling strategy employed to ameliorate occupant comfort during periods of perceived indoor warmth. An established tool for assessing the potential of climate-driven ventilation is available—namely, the \glsxtrfull{VC} potential tool, developed within the framework of the \glsxtrfull{IEA-EBC} Annex 62 project\cite{90,91,92}. This tool, structured on an Excel platform, serves as a valuable resource for early-design stage comparisons, evaluating the efficacy of diverse low-energy cooling systems across varied climatic conditions and building attributes, facilitating informed decision-making processes.

The \glsxtrshort{VC} tool, leveraging hourly climate data, computes the need for cooling in a single-zone model and identifies the most appropriate ventilative strategy for each hour throughout the year. In contrast, the proposed tool within this study allows for the simulation of various common types of natural ventilation (such as window-based, chimney/cowl, or fan-driven natural ventilation) through the dedicated \glsxtrshort{HB} component. Additionally, it discerns the specific hours during the year necessitating cooling. Moreover, an energy model constructed with \glsxtrshort{EP}, akin to the one employed in this study, boasts greater precision compared to the \glsxtrshort{VC} tool, which employs certain simplifications in its computations. These simplifications might lead to potential overestimations or underestimations of the efficacy of ventilative cooling, particularly during the summer months\cite{92}.

For the simulation, the choice is directed towards daytime natural ventilation via windows. The design allows for cross-ventilation, assuming simultaneous opening of windows on opposing walls to create a pressure gradient, thereby augmenting the potential for ventilative cooling. Allowing outdoor air to enter the indoor environment, even when it is warmer than the average indoor temperature, induces a direct physiological cooling effect on occupants. Increased airspeeds, resulting from this airflow, elevate the upper limit of comfort by enhancing the rate of sweat evaporation\cite{79}.

The volume of air flowing and its velocity inside the space depend on the operable area of the glazed surfaces facilitating natural ventilation. In this study, all zone windows are presumed fully operable in their height, with the operable area fraction ranging from 50\% to 100\%. This parameter remains subject to refinement through the optimization process. Additionally, the presence of fly screens introduces additional friction, thereby influencing airflow. Hence, \glsxtrshort{HB} accounts for this by considering a stack discharge coefficient, multiplied by the window area, which can vary from 0 (no stack ventilation) to 1, with a default coefficient assumed at 0.17.

However, recognizing that natural ventilation might not be suitable year-round, particularly during periods requiring heating, a specified temperature range for employing this passive strategy is delineated. The glazing operable area can only be opened when the outdoor temperature exceeds 12°C, and the indoor temperature is at least 25°C. This approach amplifies the efficacy of ventilative cooling, restricting its operation solely to periods when deemed necessary.




Implementing smart control systems for operable windows is essential for \glsxtrshort{CNV}. Key components include the window opener (aprifinestra automatica) or actuator (attuatore). When combined with a control system, this creates the "behavior" of the window, allowing control over when natural ventilation is activated. This is analogous to controlling a dog's mouth, facilitating heat dissipation through natural air exchange.

Within the simulation, there is a specific component for controlling natural ventilation, with a key parameter known as delta temperature. This value is typically positive, ensuring ventilation only occurs when the outdoor temperature is cooler than the indoor temperature. Negative values indicate how much hotter the outdoor temperature can be compared to the indoor temperature before ventilation ceases.

And as it is an office building the fraction ratio of operable is set to 0.15.

\paragraph{Pricing}
A set of the actuator \textit{apri finestra} with a motor and chain is 60 euro\cite{Amazon}. We need 2 to control a window, but if the \glsxtrshort{WWR} is lower than 25\% maybe 1 is sufficient. And totally we have 6 windows, so 720 euro is added into the cost. 
The running energy cost is ignored. 

\subsection{Dimmer Control}

Compliance with lighting norms is essential, with a requirement of 500 lux on the analyzed surface in office spaces. The working plane, typically situated at 0.8 meters from the ground, should receive adequate illumination. However, in practice, most \glsxtrfull{ALS} are installed on the ceiling. To achieve direct calculation based on the first principle, I place a \glsxtrshort{ALS} grid on the desk plane to measure illuminance.

For lighting compensation, if daylight is insufficient to meet the 500 lux requirement, artificial lighting is activated. The shortfall in illuminance is measured, and radiance values from the artificial light source are determined. Energy consumption is calculated by considering the luminous efficacy. The calculation takes into account the maintenance factor and utilization factor, reflecting light diffusion and reflection within the room.

In summary, if daylight falls short of 500 lux, the difference is factored into the formula, providing the energy consumption for the given period. When daylight can work autonomously, artificial lighting is solely provided for the corridor at 100 lux.

The "zero-sum" situation is evident in this context. For windows, thermal performance and \glsxtrshort{DA} represent a trade-off. Both factors contribute to energy consumption. The \glsxtrshort{WWR} is another key consideration. Balancing these factors while considering costs is a complex multi-objective problem. Demanding high thermal performance often results in reduced \glsxtrshort{DA} due to greater closure or opacity. Achieving the perfect window is challenging, as it must block UV light while maintaining high visible light transmittance. Balancing energy consumption, \glsxtrshort{DA}, and cost is a complex optimization challenge, where the algorithm plays a crucial role.
