Types of Eco-Friendly Homes

New definitions and more types of eco-friendly homes are constantly emerging, both on websites and in specialized literature. Faced with this array of options, today we wish to dedicate this article to explaining the various types of eco-friendly homes.

In this instance, we will differentiate types of eco-friendly homes based on the materials used for their construction.

Naturally, an eco-friendly home can be built from various materials, but we will establish some basic typologies and examine what each one entails.

What an Eco-Friendly Home Is Like

First and foremost, it is worthwhile to understand precisely what an eco-friendly home is.

We define an eco-friendly home as a dwelling that harnesses natural resources from the sun and earth, and furthermore, respects the environment both during its construction and once completed.

In other words, an eco-friendly home must feature a bioclimatic design and be environmentally responsible.

Bioclimatic Design

A home with a bioclimatic design aims to utilize resources offered by the environment, such as heat from the sun – or even the earth – to warm the dwelling, or air currents to ventilate and cool the rooms.

Environmental Responsibility

When we refer to an eco-friendly home being environmentally responsible, we primarily mean its materials.

We will build with materials that are natural, recyclable and/or recycled, and have a low ecological footprint – requiring minimal energy for their production and transport.

We will use materials that are respectful of the environment, but also of our health and well-being. These materials must not contain chemicals or toxins, should not alter magnetic fields within our home, and must contribute to achieving a healthy indoor environment.

Hygroscopic materials, for example, naturally regulate humidity, ensuring that our mucous membranes and respiration are not adversely affected by excessively high or low humidity levels.

Types of Eco-Friendly Homes

Let us delve into the various types of eco-friendly homes.

While an eco-friendly home can be constructed from many materials, not all meet the criteria we have just outlined.

While the first two, wood and brick, can meet all the aforementioned criteria provided their construction is respectful of the environment and people (we will examine different cases in detail).

A concrete home does not meet the criterion of being a natural and healthy material, as concrete itself contains toxic components that are neither ecological nor healthy. Therefore, it should not be classified as an eco-friendly home. However, I have decided to analyze it because many companies today market concrete homes as eco-friendly, so we will examine the pros and cons and the truth behind the claim that building with concrete is ecological.

Let’s examine each of the 3 different construction systems, each with its pros and cons.

Eco-Friendly Wooden Homes

Among the three types of eco-friendly homes we propose, let’s first consider wooden homes.

Wood is an ecological material par excellence, versatile, and imparts significant warmth to our dwelling.

Characteristics of Wood

One of the advantages of wood is its hygroscopic capacity, which helps maintain the desired indoor humidity of 50%, provided it has not been treated with varnishes that seal the pores.

Furthermore, wood also possesses good insulating properties. Although it must always be combined with thermal insulation (unless constructing a log home), wood is inherently a material that provides a certain degree of isolation from the external environment.

The second advantage is warmth. Wood brings warmth to our home.

While not a technical data point that can be numerically measured, it can certainly influence our way of living. Wooden flooring is a soft material that makes walking more comfortable, and wooden walls and floors help regulate indoor humidity. The sensation of being enveloped in a home built with a living, natural material is unique and difficult to quantify with technical data.

Regarding fire reaction, a major concern for anyone considering building a wooden home, as wood is often associated with stove fuel, it is important to understand how wood behaves in case of fire to assess the appropriate level of risk.

In fact, today, fires in wooden homes are not the result of construction defects, as they were years ago when electrical installations could produce sparks that reached and ignited the structure. Current timber construction regulations are extremely strict and do not permit any contact between sensitive points, such as electrical installation elements, and the load-bearing structure of the dwelling.

Fires in homes today are typically caused by carelessness, such as unprotected lit stoves that usually ignite sofas, carpets, or curtains first.

In any case, when a fire occurs that affects the wooden structure of a dwelling, the outermost layer of the wood burns first and carbonizes.

This charred layer then acts as a primary protection, preventing the rest of the wood from burning rapidly.

For this reason, the pillars and beams of a wooden home are usually dimensioned slightly thicker than necessary, to provide a margin of time during which this superficial layer burns.

Wood Construction

Within the types of eco-friendly homes, when we aim to build a wooden house, we must consider several points during the design phase.

The first point is to avoid glued joints as much as possible. We should use mechanical joints, meaning those formed by the wood’s shape itself, or bolted connections with metal plates.

Metal joints are currently the most common and widespread, but they can distort the magnetic fields within our home. Increasingly, metal-free joints are being revived thanks to new cutting technologies. These allow for connections between different wooden parts through interlocking pieces.

Another consideration, which offers an advantage over other types of eco-friendly homes, is that wood can be prefabricated in a workshop, arriving pre-cut and ready for on-site installation.
The ability to cut in a workshop offers greater precision, eliminating problems with fittings, and also speeds up construction. While the house’s foundations are being laid, the structure or various elements that will form part of the construction can be prepared in the workshop.

These characteristics will depend on the construction system we choose to use:

– Solid Wood

Solid wood construction is the traditional system where logs are stacked one on top of the other.

These are either regularly cut logs or round logs with notches made to interlock. This is arguably the most expensive type of wood construction, but also one of the most authentic, allowing us to appreciate wood in its full splendor.

Although the result is a solid home with excellent load-bearing capacity, care must be taken with wood settlements, especially around windows and doors, and with resolving airtightness at corners.

– Timber Frame

Timber framing is a type of construction that has also been developed over many centuries in places where wood consumption needed to be limited.

It is a much lighter structure than the solid construction system.

As its name suggests, it consists of a framework of uprights and crossbeams that act as the structure. Often, this framework needs to be reinforced with diagonals to prevent the angles between uprights and crossbeams from being affected by stresses.

Of course, once the timber frame, which acts as a skeleton, is in place, we must fill the partitions and facades. This can be done with either heavy elements – bricks, clay, adobe, etc. – or light elements – wood panels, plasterboard, etc.

– Light Wood Frame, Balloon Frame

Light wood framing is often known as balloon frame, the system used to build 90% of homes in the United States. It bears some resemblance to timber framing but is a lighter and generally more standardized structure.

To support the loads of the house, equidistant studs are used, between which thermal insulation is typically placed, so that the enclosure – the facade or interior partitions – is flush with the structure, which is not necessarily the case with timber framing.

In this case, the cladding for the structure usually consists of lightweight elements such as wood-derived panels or gypsum board, to avoid adding more load than necessary to a light structure.

Eco-Friendly Brick Homes

The second type of eco-friendly home is brick, arguably the most widely used technique in history after wood.

We must consider that there are dozens of types of bricks, each with distinct characteristics.

Characteristics of Brick

From a bioconstruction perspective, unfired clay brick is preferable, as firing requires a significant amount of energy, leading to a greater environmental impact.

The thermal performance of brick is not as good as that of wood, and in addition to applying thermal insulation, we must be very careful at corners or specific points to avoid discontinuities in the insulation.

On the other hand, its fire reaction is very good, as bricks do not burn or propagate fire that occurs indoors. As we mentioned in the case of wood, generally more care must be taken with interior finishes and furniture than with the house’s structure itself, in this case, bricks.

Brick Construction

Brick construction typically requires thicker facades and interior walls than lightweight timber systems. Consequently, the usable area of our home would be somewhat reduced compared to other options.

With brick, it is also important to consider the bonding method. The bonding materials should be cement-based adhesives, harmless from a health perspective.

Let’s look at some of the types of bricks we can use in our eco-friendly brick home.

– Lime-Sand Brick Walls

Lime-sand bricks are unfired and therefore have a better ecological balance than other conventional bricks. They are composed of 8% lime and 92% sand, which are hardened under steam pressure.

It has poor thermal performance, so we always need to reinforce it with an insulation system. However, it does offer good acoustic performance and an affordable price. Another advantage is that its smooth surfaces often allow us to forgo additional rendering.

– Cellular Concrete Block Masonry

Cellular concrete block masonry has better thermal properties than lime-sand brick and a good ecological balance compared to other concretes.

They are primarily composed of sand and supplemented with lime, cement, and gypsum.

It also offers a good range of large modular elements while remaining manageable on site.

Its weakness is its poorer performance against humidity compared to other bricks. This will demand greater rigor from the render or coating we choose to use, as we must adequately insulate the cellular concrete block from moisture.

– Natural Stone Wall

For many, a natural stone wall possesses a special charm and great durability, but it also exhibits poor thermal performance and high production costs.

To comply with current thermal regulations, it must always be furred out and reinforced with thermal insulation.

Even so, we should not dismiss stone as a facade or even interior cladding, provided it does not need to meet any thermal requirements. In such cases, we can leverage its heat accumulation capacity without compromising the thermal insulation of our home.

– Clay Construction

Clay construction is another system that has been widely used throughout the history of construction due to it being a natural material found almost everywhere.

Alongside wood, it is one of the most valued materials in the field of bioconstruction due to its environmentally friendly and health-conscious characteristics.

It performs well against fire as an incombustible material, but it is also important to note that, being a natural mixture of clay and silt, its composition is not always uniform.

One of clay’s weaknesses is that it must be protected from rain because it is not waterproof. The presence of water could alter its material characteristics and make it less durable.

It is also important to note that, precisely because of its water-absorbing capacity, it is a hygroscopic material, which means it will help maintain a constant and appropriate humidity level inside our home.

Eco-Friendly Concrete Homes

To conclude our discussion on types of eco-friendly homes, we will address concrete homes.

Concrete is an artificial stony material made from cement, aggregates, water, and, in most cases, additives to modify some of its characteristics.

It is not a material that meets all bioconstruction criteria, yet it must be considered for economic reasons when the budget is constrained.

In this case, we will focus on concrete blocks, which, in addition to faster on-site execution, are somewhat more environmentally friendly than the reinforced concrete currently in widespread use.

Characteristics of Concrete

The environment generated by a concrete home, compared to other materials, is inferior concerning humidity, the material’s surface temperature, and thermal conductivity.

That is to say, concrete does not possess good thermal capacity nor is it a hygroscopic material like wood and clay.

Concrete has a significant ecological footprint because its production requires a great deal of energy, starting with the fact that concrete blocks are often reinforced and require steel bars. Metal is one of the materials we should avoid in any type of eco-friendly home, as it is not at all ecological and does not promote a healthy indoor environment, altering the natural magnetic field of the surroundings.

Concrete Construction

Concrete is a widely used material today, so it is not difficult to find companies experienced in this now common construction system.

This also influences the construction cost, in addition to the price of the material itself.

When building with concrete blocks, care must be taken with humidity regulation on site. It should be installed as dry as possible, as it takes a long time for all absorbed water to evaporate, which can diminish the interior quality of our home.

In fact, in countries like Germany, there is a specific term to determine the recommended time between the completion of a dwelling and moving in. Although not always respected today, years ago it was very important to avoid living with excessive humidity during the structure’s drying period.

With concrete, we must also define the appropriate mortar to be used to bind the blocks. It should always be cement-based and harmless to our health.