Design Process
How to build an eco-friendly, self-sufficient home?
In today’s article, we will try to help you answer one of the most common questions we receive at the studio from our clients when they decide to build an eco-friendly home.
Often, you may not be clear on the steps to follow to carry out a build. For this reason, it is necessary to create a very basic outline from the very first meetings with the client, to establish the phases and processes for each one.
Putting this organisation in writing can be useful and practical, as building an eco-friendly, self-sufficient home is a major project that can last between a year and a half and two years, during which we will go through many different processes.
This article is intended as a basic guide on how to build an eco-friendly, self-sufficient home.
To do so, we first need to define the terms eco-friendly home and self-sufficient home, as well as understand how they are understood and how they work within the same project.
1. What is an eco-friendly home:
An eco-friendly home is a dwelling that makes use of natural resources from the sun and the earth and also respects its surroundings both during construction and once completed. It is based on bioclimatic design and is environmentally friendly.
2. What is a self-sufficient home:
The term self-sufficient already indicates the self-supplying nature of this type of dwelling, which is also known as passive houses or off-grid homes.
These are zero-consumption (or near zero-consumption) homes, as they do not need any kind of energy source or external resource input to meet their occupants’ comfort needs.
This does not mean they are eco-friendly homes, since a self-sufficient or passive house could be built with non-natural or non-eco-friendly materials, such as petroleum-based insulation.
3. What happens when we combine these concepts in a single project?
A home that takes into account the principles of an eco-friendly home and a self-sufficient one must meet both zero consumption and a bioclimatic, environmentally respectful design.
Having reviewed the key concepts, what steps should we follow to build an eco-friendly, self-sufficient home?
The truth is that the phases we are going to define today could apply both to building an eco-friendly, self-sufficient home and to a conventional home, but there are nuances: the design process for an eco home goes a step further, taking into careful account the site’s existing conditions and how they will affect the way we live.
Let’s begin!
1. Engagement and preliminary design
The approximate duration of this phase is open-ended, but we usually aim for it to last between three and six months.
This is the first stage of the project. The client gets in touch with the team that will lead the project.
We set out the working methodology and address any questions the client may have regarding the project’s development, as well as their preferences, needs, and requirements.
From here, we get started.
This is the most creative—and at the same time most complex—moment to define what your home will be like, following the principles of eco-friendly, self-sufficient architecture.
It is important that you, as clients, take an active role in this process, helping the architectural team establish a list of requirements for your future home.
In addition, you can join us on the first site visit. During it, we must study the site’s morphology in general, but also solar exposure, water runoff, the type of subsoil (through a geotechnical study), the slope, etc. This will reveal the project’s real possibilities in terms of maximising natural resources and the site’s own conditions.
With these two elements—the family’s requirements and the site—the architects can develop an initial proposal, which will then be refined to adapt and modify the design according to your ideas, needs, and budget.
To help you understand the project, it is usually recommended to work with models, hand drawings, and detailed floor plans of the home, as well as 3D images where we can choose and adjust materials and finishes.
The final result of this entire process will be a definitive project with detailed plans for the whole home, well laid out both indoors and outdoors, including the construction system, energy system, materials, and finishes.
2. Basic and detailed design
With the preliminary design finalised, it is time to define the home at a more technical and specific level. This is necessary to build the eco-friendly, self-sufficient home rigorously and to avoid mistakes that could affect the home’s energy performance.
In addition, these technical plans are required to obtain legal building licences and permits.
The technical construction project is divided into two parts: the basic project and the detailed project. The first is a more generic preliminary project that will speed up the legal procedures for obtaining the building permit from the local council.
The second is carried out in parallel with obtaining the building permit from the studio and includes the details and documentation needed to start construction.
In the basic project, we must already incorporate the energy-efficiency systems we choose, which are necessary to build an eco-friendly, self-sufficient home.
Bill of quantities
The bill of quantities is part of the detailed project and is a table-format document that includes each of the construction items for your home (materials and construction systems).
It also includes the surface area or quantity of material with an approximate price, which will later be finalised according to the construction company’s adjustments.
The final document is key to maintaining meticulous control of construction costs, avoiding budget overruns during the build.
3. Contractor tender
The final bill of quantities document is sent to three trusted construction companies so they can submit a construction budget offer. This is known as a contractor tender.
Normally, the same practice has, through experience, reliable contacts to approach and can recommend, but the final decision will always be made by the client according to their preferences.
The contractors return the completed bill of quantities document, indicating the prices for each of the home’s construction items.
With this completed table, we can compare and assess price differences and then negotiate the final price of the home with the contractor that best suits us.
The architectural team will accompany and advise you throughout the process to choose the construction company that best supports the building of your eco-friendly, self-sufficient home.
In addition, once selected, they must oversee the drafting and signing of the contract between the client and the contractor, establishing conditions and penalties in the event of omissions, errors, or delays.
4. Legal procedures
This is a period that can last between one and three months, although it is possible to speed it up by starting the procedures with the basic project.
Essentially, the goal is to obtain the building permit and licence. This is granted once the project is approved by the Architects’ Association and the local council.
5. Construction of the eco-friendly, self-sufficient home
Once we have obtained this permit, we can begin building an eco-friendly, self-sufficient home.
The architectural team, always committed to the construction process, will be responsible for overseeing and managing all processes together with a technical architect, who will handle quality controls and budget management.
Weekly site supervision is very important, as is ongoing communication with the construction team, to avoid errors in any of the construction and finishing phases or any deviations.
It is important that you, as clients, feel at ease, and this is achieved by establishing a relationship of trust and continuous communication with the team managing your home project.
6. Completion of the works
The last procedure required before you can move into your eco-friendly, self-sufficient home is, quite simply, to prepare the documentation needed to legalise the home and close out the construction process.
In addition, another important point at this stage is supporting the client to help them understand how the home works and how to use passive architecture elements to save energy, as well as to live in a healthy indoor environment.
The architectural team we have worked with throughout the process will be best placed to show us how our eco-friendly, self-sufficient home works, as they understand the home and its passive and active systems better than anyone.
With small actions such as ventilating at the right time and for the right duration, or using solar shading elements correctly, we can achieve a cool home in summer and a warm one in winter, greatly reducing heating and cooling costs.