Design Process
Design of a 200 m² Eco-Friendly Home
In recent years, banks have been offering more favorable terms for mortgages, which has led to a progressive increase in the minimum sizes of the homes we are commissioned to design.
The number of families requesting the design of a 200 m² eco-friendly home is growing, but:
What does designing a 200 m² home actually entail?
For some families with many children, and where one or more family members work from home, 200 m² is the minimum area needed to accommodate 4 or 5 bedrooms or study spaces.
For other families, 200 m² may mean 3 very large and spacious bedrooms and an ample living room and kitchen.
In any case, at Slow Studio we always remind you of the need to maintain a balance between your needs and the requirements for efficiency and a healthy home. Any home project starts with a maximum budget that we do not want to exceed, and in this regard it is important to decide whether we want to maximize the square meters of the home or allocate part of the budget to achieve greater efficiency or even zero consumption.
Today we discuss all the considerations when deciding on the design of a 200 m² eco-friendly home to have all the necessary information to determine the total square meters we need that will be useful for our family—without having residual unused spaces and making the most of the best layout according to our lifestyle.
Additionally, as usual, today’s article reviews basic topics on eco-friendly design, materials, and construction techniques that can help make a home much more sustainable, healthy, and environmentally friendly.
Let’s begin!
What Eco-Friendly Homes Are and What They Look Like
Before delving into the design principles of a 200 m² eco-friendly home, we want to remind you what building an eco-friendly home is all about.
An eco-friendly home is one that harnesses and draws from natural resources such as the sun or natural ventilation. Additionally, it respects the environment both during construction and once completed.
An eco-friendly home bases its design on bioclimatic design and is environmentally friendly.
At our studio Slow Studio, we believe that the three pillars of an eco-friendly home are adaptation to the family’s needs, efficiency, and health. For this reason, we design passive houses that are also built with natural materials—a decision that allows us to create healthy, toxin-free spaces, promoting good health for their occupants, which is undoubtedly priceless!
Another positive aspect of this type of home is the energy savings they achieve once in operation. Typically, in a conventional home, we spend more than 60% of energy on heating.
An eco-friendly home works with passive systems such as solar capture, thermal mass storage in walls, good insulation, and airtight walls that allow us to build homes that function without heating.
Design of a 200 m² Eco-Friendly Home
Structure
The first step in designing a 200 m² eco-friendly home will be to plan and design its structure, as it is the skeleton of the home and the element that will support the entire construction.
Generally, the structure of a 200 m² eco-friendly home does not differ much from conventional homes of that size.
We must, however, ensure that the materials are natural, eco-friendly, and durable.
Construction materials, including the structure, should be sustainable throughout their entire life cycle—that is, they should have a low environmental impact throughout their extraction, transformation, and installation on site.
Some examples of eco-friendly materials are brick or wood, although it is necessary to evaluate each case individually, including its origin and composition.
Steel, despite being a good structural material, would not be suitable for the design of a 200 m² eco-friendly home as it is a material with a high environmental impact.
For its transformation into a construction element, steel must be heated to a temperature between 800 and 1,000°C, requiring significant energy consumption in its production. Additionally, steel interferes with the Earth’s natural magnetic field and can increase static electricity in the home.
Façades
Secondly, the design of a 200 m² eco-friendly home will also consider the design of all the building’s façades (including the roof).
The orientation of each will play a determining role in establishing the number of openings in the façade, the thickness of the wall, the materials used, etc., primarily based on the solar radiation they receive and which can therefore be harnessed as energy for the use and operation of the home.
– North Façade: In the Northern Hemisphere, the sun moves from east to west passing through the south. Thus, north-facing façades do not receive direct radiation throughout the day.
These are humid and cool areas, whose diffuse light remains fairly consistent throughout the day.
Therefore, a north façade must be very well insulated to prevent energy loss from inside to outside the home, while also protecting against exterior moisture.
Unless a specific use of a room requires it, it is recommended to have the minimum number of openings, and therefore window surfaces, possible. When we refer to a specific use, we mean that sometimes our clients’ hobbies may require spaces with a specific type of lighting, which is easily found in the north
orientation, for example: for painting, reading, dancing…
– South Façade: unlike the previous one, the south façade receives the most hours of solar radiation throughout the day. Therefore, it should take advantage of the light and greenhouse effect that large windows can provide, always keeping in mind that in summer, elements such as solar filters or awnings must be installed to protect against excessive radiation.
The walls of this façade will perform better if they have a considerable thickness. This will improve their thermal mass, allowing them to accumulate heat during the day and release it during cooler hours into the interior of the home.
– East and West Façades: these are two façades that receive the sun at its lowest hours, both at sunrise and sunset.
This is usually weak radiation but with a very horizontal angle, an aspect that can negatively influence the design of a 200 m² eco-friendly home by causing visual discomfort to its occupants. Therefore, the openings we design will be smaller, and we will also install solar protection systems in the form of louvers or shutters to protect against excessive radiation and lighting.
– The Roof: the roof is an exceptional façade that we often forget to consider.
Of all those mentioned above, the roof receives solar radiation all hours of the day. It must therefore be treated with great care, as we can harness significant energy and water from it, while also causing problems if its design is not properly executed.
There are many types and roof systems: pitched roof, flat roof, green roof, water-flooded roof, etc. All of them are perfectly adaptable to the design of a 200 m² eco-friendly home. In today’s article, we will focus more on the strategies to follow to achieve an optimal, functional, and above all sustainable result, rather than on the types.
We must properly insulate and waterproof the roof to prevent water infiltration or energy loss. Installing solar panels can help us achieve extra energy for the home’s use as well as for heating water.
We can also install a rainwater collection and filtration system that we can use for domestic purposes (not for consumption) as well as for watering plants and the garden.
Layout
The layout for the design of a 200 m² eco-friendly home will also consider the orientation of the rooms based on their use and the user’s needs.
The main design factors for a 200 m² eco-friendly home that will determine part of the well-being within it are:
First, that the sizing of the spaces is in accordance with the user’s needs.
That the floor plan layout is comfortable, practical, coherent, and with an architectural morphology integrated into the environment and with harmonious forms.
We can place daytime-use rooms in areas that receive lighting during the day, such as south, east, and west. On the other hand, service rooms, storage areas, or simply those rooms used at night that do not take as much advantage of natural lighting can be located in north-facing areas.
Additionally, light and color will be equally important when building an eco-friendly home. If we treat lighting so that it can adapt to tasks and make use of natural light, we will activate our organism according to the needs of each moment.
There are many options for laying out a 200 m² eco-friendly home.
– One option may be to focus on common areas and the kitchen, making these the largest and most spacious (50–80 m²) and leaving the remainder for 2-3 bedrooms and 1 or 2 bathrooms.
– Another option may be to invest in bedrooms to achieve greater flexibility of uses (office, storage, workshop, music room, guest room, etc.) as well as to have more capacity for occupants in anticipation of wanting to expand the family or frequently host friends or relatives.
– Finally, a classic approach: distribute the 200 m² with a medium-sized kitchen and living-dining room, connected to a small study to be able to work from home and keep an eye on the children while they play peacefully. As for the bedrooms, these can be two doubles (one en-suite and another with a separate bathroom), or three bedrooms (one en-suite and two singles).
To conclude this section on layout within the design of a 200 m² eco-friendly home, it is important to highlight the difference between dividing the home across multiple floors or having the entire program on a single level.
When we add floors to a home, much space will be lost to vertical circulation (optional elevator and stairs).
Although we recommend, both for comfort and space optimization, designing a 200 m² eco-friendly home on a single floor, this aspect depends directly on the size and characteristics of the land or plot.
Climate Control
1. Humidity:
Controlling and regulating indoor atmospheric humidity naturally will be possible through the use of hygroscopic materials. These materials are capable of absorbing moisture from their environment thanks to their porosity.
If we consider using these materials for the design of a 200 m² eco-friendly home, we will be able to regulate our home’s humidity naturally. Due to their characteristics, hygroscopic materials absorb moisture when there is too much in the environment—for example, after cooking or showering—and release it when the environment is excessively dry—for example, after several hours of heating without natural ventilation.
2. Thermal Insulation vs. Heat Accumulation:
Finding the balance between these two aspects is vital to achieving good performance and design of a 200 m² eco-friendly home.
While it is fashionable today to heavily insulate homes as it seems to be the magic formula for energy efficiency, we must not forget that efficiency is also achieved by making materials work in our favor.
Therefore, it is important to know how to combine good insulation with heat accumulation through walls of great mass and density that can store the sun’s heat and release it after a few hours.
3. Indoor Temperature:
Generally, even if we manage to significantly reduce energy consumption through passive capture systems, the indoor temperature of an eco-friendly home will be regulated by a heating system. But if we do not have good insulation in the walls and the walls are cold, we may not only suffer condensation and moisture but also have cold radiating surfaces that reduce the efficiency of our climate control systems.
Obviously, the home’s temperature will greatly influence our well-being and comfort. It will be advisable to use materials that are rather warm or capable of accumulating heat from the sun or from a radiant heating system.
Generally, it is recommended that the indoor ambient air be at a temperature between 18 and 22°C, depending on whether it is a living area, a hallway, or a bathroom where the temperature should be somewhat warmer.
4. Air Quality:
Having good air quality at home will also be vital for the design of a 200 m² eco-friendly home.
Despite being an aspect that directly affects the health of occupants, we are still somewhat behind in this area, and most homes today have indoor air of lower quality than outdoor air. This means it is likely more laden with CO2 and contaminants from the home itself, such as dust, moisture and mold, and other contaminants from non-natural construction products or materials.
Additionally, most heating systems tend to dry out the environment and reduce relative humidity.
An ambient humidity of around 50% is sufficient for our body to keep its defenses alert and for the indoor thermal sensation to be adequate.
Materials
Finally, we could not fail to mention some basic aspects regarding materials for the design of a 200 m² eco-friendly home.
First, both for an eco-friendly home and for any conventional dwelling, we should consider today the exclusive or nearly exclusive use of eco-friendly and natural materials.
Wood and brick are two examples that not only come from extraction and transformation processes with a low ecological footprint but also, once in the home, are excellent regulators of indoor humidity.
Taking for granted that our home will need to use other materials both for the structure and for façade and interior finishes, we also recommend avoiding combining too many different materials. That is, we should always work with the fewest possible materials, as thermal bridges and assembly problem areas are generated at joints, seams, and material transitions.
As we have already mentioned, we should use:
– Sustainable materials
– Natural materials, that is, minimally processed materials that guarantee being free of toxins, such as stone or untreated wood.
– Breathable materials, those that have a certain natural porosity that allows them to absorb and release ambient moisture, improving the indoor climate of the home.
– Toxin-free materials that ensure they do not contain hazardous ingredients in their composition that could put the health of a home’s occupants at risk.
– Finally, we should always try to prioritize locally sourced materials, that is, those that come from an area close to where construction takes place. This gesture contributes to reducing both transportation costs and environmental pollution, while also promoting the local economy.
An Example: Marc and Rebeca’s Home
There is no better way to conclude the article than with an example of a 200 m² eco-friendly home design that we have developed at our studio Slow Studio.
This is a home built on an exceptional plot—spacious, level, and south-facing—which provided complete freedom in positioning the home.
The construction is located in the northern part of the plot, on one hand maximizing the outdoor space to the south but also to optimize the land area and be able to build all the rooms on a single floor.
The fantastic location allows all rooms to take advantage of the south orientation, both daytime and nighttime areas.
In summer, this area is protected by a porch. The only exception is found in the bathrooms and service areas, which are on the north façade of the home and open toward the patios to maintain the occupants’ privacy by avoiding direct view from neighbors.
The structure of this home consists of concrete block walls, a construction system with high thermal mass that will help us accumulate heat and regulate temperature both in winter and summer, while the exterior finish is achieved through external thermal insulation finished with mortar.
The roof is pitched and tiled and forms a double-height space in the central part of the home to provide the living area with a loft for reading and relaxation.
If you found the article interesting and want to know more, or if you are considering building a home that meets the design principles of a 200 m² eco-friendly home as we have explained above, you can contact our studio Slow Studio or come meet us at our office in Barcelona.