Healthy Bedroom Design

Sleep is vital for our survival. When we sleep, our body regenerates and recovers the energy lost during daytime activity. However, for sleep to be effective, we must ensure conditions of well-being influenced by various environmental factors. Healthy bedroom design that promotes deep rest is essential to ensure restorative sleep that contributes to improving our quality of life.

While experts have not managed to decipher the reason why we sleep, it does seem clear that there is a close relationship between the sleep process and our physical and psychological health. In fact, the World Health Organization (WHO) insists that sleeping is not a pleasure but a necessity—a time of rest that allows our organism to function optimally.

In this regard, healthy bedroom design will be based on several key factors that will ensure our rest and well-being:

– First, it will be necessary to have a healthy space with a healthy indoor environment, free of noise, with the possibility of controlling both natural and artificial lighting, and free of toxins or allergens, as well as free of electromagnetic fields that alter our organism.

– Second, we must ensure that the structure and elements that make up the resting surface—the bed— on which we rest has specific conditions of ergonomics and materials to minimally interfere with the natural physiology of our organism.

– Finally, we will consider the composition and quality of the fabrics that make up the bed linens on which we rest, as well as the blankets or duvets with which we cover ourselves.

The following article has been divided according to these three chapters that affect sleep quality and people’s well-being: the environment of a healthy bedroom, the structure and components of the bed, and its fabrics:

1 BEDROOM INDOOR ENVIRONMENT

2 STRUCTURE AND ELEMENTS THAT MAKE UP THE BED

3 COMPOSITION OF BED LINEN FABRIC

THE INDOOR ENVIRONMENT OF A BEDROOM

A large part of our life takes place in this interior space we call the bedroom. Therefore, quality sleep is directly related to hygrothermal, lighting, and sound conditions, or even other factors that can directly affect our emotional state, such as the smells or colors that compose it.

The factors that define the quality of a bedroom are closely related to the factors that define the quality of a home’s indoor environment. However, there are some peculiarities regarding light, noise, or the ideal temperature and humidity that promote deep rest and are especially important in the resting space.

To ensure environmental quality in a bedroom, we must optimize the following factors: maintain adequate temperature and humidity, ensure air quality, reduce noise, achieve total lighting control, ensure the absence of electromagnetic fields, and use natural materials free of toxins and contaminants both in construction and finishes as well as in ecological furniture. Let us examine each factor in detail:

1 Adequate temperature for HEALTHY BEDROOM DESIGN

While we sleep, our body experiences a slight drop in temperature. This occurs because our organism places thermoregulatory functions that allow us to control our body temperature in second place.

The inability of internal regulation makes our body temperature more susceptible to ambient temperature, making it one of the most significant factors regarding sleep quality.

Considering that body temperature drops during the night, the comfort temperature of our bedroom is around 18 degrees, creating a cool environment that, in addition to favoring the regulation that the body does not do by itself, also promotes deep breathing.

Although the average is 18 degrees, comfort temperature is very relative and can vary from one individual to another. Therefore, there is a comfort range that extends between 15.6 and 19.4 degrees. [4]

When the temperature of our bedroom does not adjust to comfort conditions, there will be either a sensation of cold or excess heat that will, to some extent, produce sleep disturbance.

If our bedroom is too warm, it will not only affect sleep onset due to the sensation of discomfort, but will also reduce the time we spend in REM phase, preventing proper body recovery and negatively affecting the immune system. Additionally, sleep is more likely to be interrupted and we will experience a greater sensation of fatigue.

On the other hand, although exposure to cold is not considered as harmful as excess heat, it is true that it can also cause discomfort, affect the REM phase, and be associated with blood pressure problems.

Lowering the thermostat at night, closing blinds during the day to avoid heat accumulation in the bedroom in summer, and keeping them raised in winter to maximize sunlight are small actions that can help us optimize the temperature of our room.

2 Ideal humidity for sleeping

Humidity is the second factor that influences achieving a healthy indoor environment in a bedroom. In fact, to have effective temperature control and achieve a cool environment, adequate humidity control is necessary.

The established values for ideal average relative humidity range between 40% and 60%.

It has been shown that spaces where humidity is above 40% improve sleep quality, promoting deep rest and reducing apnea.

However, this humidity should not exceed values above 60%, as adverse effects can occur.

Excess humidity produces fatigue, which makes it difficult to fall asleep, but also favors the appearance of unhealthy domestic microorganisms that promote mold and dampness that directly affect our health.

However, in many cases, due to improper and excessive use of heating or air conditioning systems, which promote the reduction of ambient relative humidity, the humidity in our homes tends to be excessively dry, with values that in many cases are below 20%.

Excessively low humidity values lead to the loss of protection of our mucous membranes, which lose their natural barrier, exposing our organism to the entry of viruses and bacteria.

To avoid dryness problems and ensure that the room’s humidity is adequate, it is necessary to guarantee proper ventilation through healthy bedroom design.

3 Adequate ventilation for HEALTHY BEDROOM DESIGN

Ensuring proper ventilation and constant air renewal in the bedroom is essential to achieve adequate air quality, as well as natural regulation of the relative humidity of the indoor environment.

Advances in energy efficiency and increasingly demanding new construction regulations regarding building airtightness with the aim of reducing temperature exchange with the outside and reducing energy consumption entail the need to ensure mechanical renewal of indoor air.

While in new-build buildings, air exchange is ensured by mechanical means, in older buildings air exchange is often insufficient and its quality can be reduced simply by the CO₂ emissions from the people who live in them.

In addition to CO₂ accumulation, air pollutants can come from both outside and inside the home:

Indoor environment pollutants in our homes are determined by CO₂ accumulations generated by the users themselves; by excess humidity that favors the appearance of mold; or by construction materials, finishes, and furniture that may incorporate toxins.

Also, cleaning products or gases derived from combustion (such as carbon monoxide) produced in fireplaces, stoves, or kitchens can be toxic, so it is important to be aware of their use both in the bedroom and in the rest of the home and always ensure proper ventilation in spaces where combustion occurs and therefore oxygen consumption.

At the same time, air pollution can originate from agents coming from outside, such as harmful emissions from the ground itself like radon, or derived from combustion and industrial processes near our home, such as smoke, carbon monoxide, nitrogen dioxide, or hydrocarbons (PAH). [6]

Air quality meters

The level of CO₂ concentration is considered one of the main indicators of air quality in a home, since whenever it is occupied it will accumulate CO₂ emitted by the users themselves. Measuring whether this CO₂ is extracted and renewed with fresh air from outside gives us clues to know if the rest of the pollutants have also been extracted.

For this reason, the most recent version of the Technical Building Code (CTE), in its Basic Document HS Health, HS-3 Indoor Air Quality, establishes that homes must have a ventilation system that guarantees minimum ventilation flows and favors an average annual CO₂ concentration below 800 ppm. [7]

Having a CO₂ detector, whose use has spread following the COVID-19 pandemic, will help us easily detect when indoor air is stale. While the balanced use between natural ventilation systems through operable enclosures and mechanical ventilation systems through automated CO₂ or pressure sensors will allow us to guarantee adequate air renewal.

In old homes where there is no choice but to ventilate manually, and especially in the case of bedrooms where we will spend several hours without ventilation control, it is possible to leave a window slightly open, either in the room itself or in a room near where we sleep.

4 Impact of noise on sleep quality

Healthy bedroom design provides acoustic levels that guarantee deep rest.

Exposure to excessively intense or continuous noise has been shown to alter our sleep and, in turn, have short- and long-term effects on our health.

Noise during the night can result in fragmented sleep that promotes irritability, drowsiness, and psychological discomfort. Likewise, prolonged exposure is related to high blood pressure, cardiovascular risk, and weakening of the immune system, which remains on constant alert.

Considering that around 55% of the world’s population lives in cities, it is very common that when we sleep, we have to coexist with traffic noise, crowds of people, street activities, neighbors, or even airplanes.

In the case of people living in smaller or rural towns, noise produced by neighbors, weather phenomena, pets, industries and transportation, or generated by appliances in our own home must also be considered.

If we do not live in a quiet area and cannot locate the bedroom away from acoustic emissions that disturb our sleep, the solution involves carrying out a complete soundproofing intervention of the bedroom, considering whether the noise emission sources are airborne (such as those from the street itself) or impact (such as noise generated by the movement of a neighbor’s chair or the vibration of a refrigerator or washing machine).

To protect ourselves from external noise, a very important factor is having good window insulation to avoid acoustic bridges, as well as thermal bridges, obtaining good acoustic insulation and at the same time greater thermal control of the room.

Another solution is the use of dampening surfaces, which are thick, dense, or undulating materials, such as curtains or rugs, that favor dampening of noise generated by neighbors or other external aggressions.

Regarding noise produced by appliances or air conditioning systems in our home, we should try to choose those that are as quiet as possible. There are increasingly more appliances with silent systems or programs that allow them to be started automatically during hours that do not interrupt rest.

Additionally, to avoid sleep fragmentation, it is advisable that unnecessary alarms and notifications from these appliances and mobile devices be deactivated.

In the event that these measures are not possible, we can resort to earplugs or background sounds. In fact, there are a couple of sounds known as white noise or pink noise that help mask noises we cannot control in our bedroom environment and promote falling asleep. [8]

5 Bedroom lighting to achieve well-being

Light and sleep quality maintain a very important link. For this reason, lighting regulation in healthy bedroom design will be essential for our well-being.

People have a biological clock that has adapted to sunlight patterns, synchronizing with sunrise and sunset. Thus, our body distinguishes between staying active while there is light and resting when it begins to get dark.

However, electricity generated by fossil or nuclear sources allows us to have light during nighttime hours, generating very significant light pollution that is harmful to our health, since this constant exposure to light has effects on the functioning of our biological clock, sleep cycles, and melatonin production.

The internal clock responsible for coordinating all the processes of our body is what is known as the circadian rhythm. Prolonged exposure to light during dusk alters our circadian rhythm and is related to worsening metabolism and cardiovascular problems.

High exposure to artificial light during the hours before falling asleep can interrupt sleep cycles, resulting in fragmented sleep that will not allow our body to have the necessary time to go through all the deeper and more restorative sleep stages.

The more altered the sleep cycle is, the more likely melatonin production is also altered. Melatonin is a hormone produced by our body naturally that begins in response to darkness and helps us fall asleep. If there is exposure to light at inappropriate hours, this production stops, making sleep difficult and altering the circadian rhythm. [9]

Configuring our bedroom to be as dark as possible during the night, using blackout curtains that prevent street light from entering, is a measure we can take to promote quality sleep. Also, using not very intense and warm lights will promote healthy bedroom design.

6 Impact of electromagnetic fields (EMF) on sleep quality

The nervous system and the various chemical processes that occur in our organism produce small electrical currents. This charge from the body itself interacts with the electrical and magnetic charges of the terrestrial environment, both natural and artificial.

While our organism has evolved thanks to natural electromagnetic fields, this is not the case with artificial electromagnetic fields that have developed in recent centuries extremely rapidly, practically without regulation and without studies to support their harmlessness.

The WHO considers electromagnetic fields (EMF) an “emerging risk” and the International Agency for Research on Cancer (IARC) classifies them as possible carcinogens if significant exposure to these sources accumulates. [11]

Today, we are exposed to a large amount of electrical and magnetic radiation.

These can come from emissions outside the home, such as those emitted by mobile phone antennas, radars, telecommunications networks, or nearby high-voltage lines, or from sources inside the home, such as those from wireless networks of all kinds: Wi-Fi, mobile phones or cordless phones, direct radiation generated by microwaves or induction cooktops, or some appliances, especially those that are beginning to be connected according to the so-called Internet of Things.

Bedrooms are spaces where the body rests and recovers, regenerates cells, and carries out biological processes that prepare it for the new day, and any minimal alteration can interfere with the natural regeneration of our organism.

To reduce this exposure, we will consider two factors.

First, the design of the electrical installation in our home, which should primarily be carried out in a star distribution design that allows reducing the power of each circuit so that the generated magnetic fields are smaller.

Additionally, regarding wiring, it should be avoided in any long-stay area such as bed headboards and, as far as possible, be carried out using halogen-free filaments.

If we cannot modify the home’s installation, we can always install an automatic electrical disconnector, known as a bioswitch. This is a device installed in the home’s main panel that can detect when there is no demand for electrical supply, disconnecting the 230V voltage and leaving a minimum direct current voltage that allows detecting when alternating supply is needed again, eliminating any type of electrical field during rest hours.

Undoubtedly, one of the best recommendations for reducing electrical and electromagnetic fields during rest hours is achieving healthy habits of reducing exposure during the night, such as disconnecting the Wi-Fi network, switching cordless phones to ECO mode so they only emit electromagnetic waves when in use, or leaving the mobile phone in airplane mode charging outside the room and away from rest areas.

To evaluate exposure to electromagnetic fields in our home, it is possible to carry out a field impact study with a biohabitability expert, in which case it is always advisable to follow the reference values of the Baubiologie measurement standard for rest spaces. [12]

7 Natural materials for HEALTHY BEDROOM DESIGN

Lastly, a bedroom’s environmental comfort is also linked to the materials and finishes of walls, floors and joinery, as well as the room layout and the colours used in this space, which will influence visual perception and the sense of wellbeing in one way or another.

When it comes to materials, in healthy bedroom design we should use those that are water-vapour permeable, natural and breathable, toxin-free and odourless. [13]

A bedroom with clay walls (a breathable material) will not be the same as one with cement walls (non-permeable). Likewise, the sensations will also be different depending on whether the bedroom has a wooden floor, a stone floor, or a synthetic one.

For wall, floor and joinery finishes, in addition to considering the physical characteristics of the materials, precautions should also be taken because, nowadays, most of those used release toxins that can harm health. [14]

In addition, building materials and finishes also influence visual perception depending on their tone and defining colours. For most people, warm, soft colours create a greater sense of comfort. [15]

ERGONOMIC BED DESIGN

We spend around a third of our lives in bed, so it is undoubtedly one of the most important pieces of furniture in our home—one we should invest in thoughtfully and pay attention to the lifespan of each component, so we can repair, clean or replace them at the right time without compromising our health.

A good base

For good rest, the bed base should be neither too soft nor too hard. A base that is overly flexible or too hard can make it difficult to adopt the correct posture, causing spinal arching that can lead to muscle contractions and chronic injuries.

The firmness of the base depends mainly on its material and design. Sleeping on a base with an opaque, dense surface such as particleboard is not the same as sleeping on a slatted bed base.

Elastic elements such as wooden slats are better than solid-surface bases because, in addition to being more breathable, they allow a certain flexibility, supporting healthier sleep.

As for the material, it is recommended that the slats be made of solid wood, glued laminated wood, or bamboo cylinders, a highly flexible material. In addition, it is preferable that the base contains no metal parts that conduct electromagnetic fields.

In addition, the slats should not be varnished, as conventional varnish is a chemical compound that releases volatile organic compounds (VOCs) into the environment, which accumulate in the air we breathe. It also forms an impermeable film that prevents the wood from breathing naturally and encourages mould growth, which can easily spread to the mattress.

Finally, the support of these slats on the base should preferably be done using latex strips, coconut fibre, or rubber profiles. In this way, the base achieves greater flexibility, improving rest.

– Multi-zone slatted bed bases

Multi-zone slatted bed bases are an example of elastic elements capable of promoting good rest. They can be adjusted to the body’s weight, helping to prevent back discomfort. Even without a mattress, we could sleep on them without feeling pain.

– Tatamis

The tatami comes from Japanese culture, where the term refers to the semi-soft flooring used in sleeping and living spaces in the traditional Japanese home.

When adopted in Western culture, the word tatami refers to the bed base typically used to support a futon, but it is based on the idea of a flat surface raised off the floor, made of a breathable material, designed to remain visible when the futon is folded and even to be used as a sitting area during the day.

Traditional tatami is made exclusively from natural materials. It consists of a box covered with a polished wicker mat, from a species of climbing cane in the palm family. The interior is made of a material known as igusa, produced from a plant called Juncus effusus (translated as soft rush or mat rush).

Mat rush is a herbaceous plant that is very common in Asia, from the rice family. The fibre of this plant undergoes a tightly controlled compaction and heat process that transforms it into igusa.

This material works as a good thermal insulator and also allows the mattress to breathe. For this reason, it is beneficial in winter, as it helps keep heat inside the bedroom or home. In summer, however, it offers a more pleasant coolness than fabric upholstery. [16]

The Importance of Mattresses IN THE DESIGN OF HEALTHY BEDROOMS

A good mattress works with elastic elements to promote deep rest, cradling the prominent parts of the body and always keeping the spine straight. Additionally, it must allow the body to breathe and be free of toxins.

Thickness is one of the main characteristics to consider in the design of healthy bedrooms. A thickness between 6 and 10 cm is considered appropriate, varying depending on body weight. If a mattress is too thick, the effects of the elastic elements will be nullified, and therefore, the desired balance between firmness and elasticity will not be achieved.

The material is another of the most relevant factors defining mattress quality. Materials such as springs, kapok fibers (a tropical tree called the silk-cotton tree), sheep’s wool, horsehair, coconut fibers, natural latex without synthetic parts, or a combination of some of these can be used. The use of these raw materials results in different types of mattresses: spring, natural material, natural latex, synthetic latex, and foam mattresses.

– Natural Fibers

Mattresses made with natural materials are those that use fibers such as wool, linen, cotton, hemp, or horsehair.

Mostly, a combination of these fibers is used for the manufacture of natural fiber mattresses. The interior of the mattress can be composed of wool, or layers of wool and cotton interspersed with latex.

It is also possible to manufacture exclusively plant-based mattresses, using a core with soybean oil extracts and layers of cotton plus hemp, linen, and bamboo.

These layers are secured by cotton tufts, which may or may not be braided, that pass through the mattress from top to bottom.

For its part, the vegetable horsehair filling is made from the fiber and material from fields that were formerly used to fill mattresses. It is a natural, strong, slightly elastic fiber that absorbs moisture very well. [17]

The covers of natural material mattresses are woven from cotton and linen.

– Natural Latex

Among these types of mattresses, natural latex stands out, presenting particularly optimal characteristics for mattress manufacturing. This material offers excellent body adaptability. That is, it yields at points where more pressure is applied but returns to its original position if pressure points vary when the person changes sleeping position.

However, natural latex is not hygroscopic; that is, it does not absorb and release moisture, but rather is similar to a waterproof material, preventing natural sweat transpiration. This defect can be compensated for by using a good mattress topper and cover, or by means of air chambers or vertical air channels located within the mattress itself.

A natural option is sheep’s wool or camel hair mattress toppers, which promote moisture absorption without feeling damp to the touch and without losing thermal capacity.

In 1994, the Association for the Quality of Environmentally Compatible Latex Mattresses was founded to establish criteria for natural mattresses as an alternative to foams and synthetic latex.

The association grants the QUL quality seal, which indicates that the mattress is made of 100% natural latex and meets health safety requirements for people and environmental respect. [18]

– Spring Mattresses

Spring mattresses tend to deteriorate unevenly, creating areas of greater and lesser pressure that negatively affect sleep quality and can cause spinal injuries.

Furthermore, just like metallic bed frames, springs can be affected by electromagnetic fields; we must not forget that springs are conductive metallic material.

– Futons

As an alternative to latex and if opting for the tatami option, we find Japanese-origin mattresses highly valued in terms of rest.

This element is handcrafted, using 100% natural fiber such as cotton, which allows for thermal regulation and optimal breathability. It usually starts with a pure cotton sheet about 2 cm thick, protected inside a cotton cover.

In some cases, we find the Westernized version of the futon, which includes an intermediate latex layer between 5 and 10 cm thick. [16]

The futon on a tatami base combination is optimal because, in addition to its natural origin, the characteristics of the tatami allow the futon to breathe. If a tatami is not used, a solid wood slatted bed base can be used, but always ensuring good breathability and air circulation to prevent moisture accumulation and ensure its hygiene.

The pillow

Choosing the right pillow is essential to ensure good rest and support healthy bedroom design, as it can affect the posture adopted by the spine in the neck area, a zone that is very sensitive to contractions.

In fact, studies show that pillows have a greater influence on sleep depth than mattress types.

The design of the ideal pillow mainly adapts to sleeping position and body dimensions in order to maintain the natural position of the head and neck. [19] Therefore, the two most relevant parameters to consider are thickness and contact pressure. [20]

Following these orthopaedic reasons, a position without head elevation is especially recommended, or a simple elastic cervical roll, rather soft, about 4 to 6 cm in diameter.

If the slatted bed base is of good quality, you can even do without a pillow, as it adapts to the most prominent areas and manages to keep the spine straight at every point.

SUITABLE TEXTILES FOR REST

The last layer protecting the base, mattress, and pillow set is the textiles that come into contact with the skin. For this reason, it will be necessary to opt for natural fabrics, free of chemical agents that could come into contact with the skin or mucous membranes.

Furthermore, health refers not only to the harmlessness of the fabrics used but also to the feeling of well-being and comfort we experience when we are covered and in contact with a natural fabric.

Comfort in relation to textiles is determined by touch, natural moisture regulation, and the correct balance between thermal insulation and heat dissipation.

Factors such as material type, thickness, clothing insulation, the volume of air trapped in the fibers, resistance to water vapor diffusion, clothing layers, body fit, and air permeability directly influence the quality of our sleep. Additionally, thermal sensations vary greatly from one individual to another. [21]

Other aspects to consider are electrostatic charges that directly affect sleep quality or toxic emanations from non-natural fabrics.

The factors mentioned in relation to the type of textile, along with the human factor—that is, the metabolic rate determined by the body’s activity level—will create a characteristic bed microclimate that influences sleep depth. Sweating or feeling cold can be an indicator that this microclimate is not adequate.