Wouldn’t it be awesome if you were able to design and create an eco-home that was not only visually attractive but also had really low energy demand?
As you probably already know, both the building industry and homeowners understand the need for sustainable homes and living in the face of a changing world and in a changing UK housing market. The construction of new houses, the rehabilitation of homes and the enhancement of existing housing stock are all necessary steps in meeting the demand for housing in the UK and if you’re considering your own self build or investing in new housing that some focus must be put on sustainability and eco-friendliness as these are key components that people in today’s market desire.
Addressing energy efficiency in buildings achieves the full value in terms of energy conservation. Using the technologies available to the industry today, it is possible to increase the energy efficiency of new buildings and renovations without compromising the aesthetics, building safeguards, health or thermal comfort of the occupants of the building. Energy-efficient construction allows energy efficiency to be a core part of the design of eco-houses.
Would You Like To Learn How To Develop An Eco-Friendly Home In The UK?
If you follow the best practices outlined in this blog post, you’ll be well on your way to building an eco-house that is visually attractive and has a low energy demand right from the get go Let’s take a closer look at how to design and create a low-energy, eco-friendly house with the new Passivhaus architecture and sustainable design ideas.
Best Passivhaus Design & Construction Strategies
First of all, Passivhaus architecture is a model for design and construction that strives to build homes that remain at a comfortable temperature and uses minimal energy. Sunlight, human and electrical heat produced are used to significantly reduce the need for additional space heating.
In the Passivhaus architecture, the scale, shape and orientation of the house, air tightness, good heat retention, natural ventilation and heat recovery systems are all used with the goal of significantly reducing the annual carbon emissions of the building.
Here’s the point: In order to meet the Passivhaus requirement, the energy needed for space heating must not exceed 15 kWh / m2. It is calculated by measuring the maximum amount of heat that can be supplied with fresh air at the minimum necessary rate of ventilation. So, what does all this mean?
The achievement of this level depends to a large extent on the climatic condition of the area in which it is constructed. In the United Kingdom, this usually involves:
- Ensuring a very high standard of insulation
- Installing highly high-performance windows with insulated frames
- The airtight structure of the building
- ‘free thermal bridge’ construction
- A hydraulic ventilation system with a highly effective heat recovery system
- Precise construction using the Passive House Planning Program (PHPP).
Passive Solar Design requirements for Sustainable Homes
The great news is that you don’t have to adhere to the Passivhaus norm to recognize and use passive energy sources. Many people are familiar with successful solar energy production – solar panels are a common sight in the UK and help reduce our reliance on polluting fossil fuels.
Fewer people recognize the need for passive solar architecture, which helps us to use the heat and light of the sun more directly to reduce the energy requirements of our homes.
The reality is that building orientation is one of the most essential aspects of passive solar architecture.
Let me explain it to you like this:
New buildings, whenever possible, should be designed in such a way that they face south (in the Northern Hemisphere). Windows should be positioned mainly on the south side of the building to maximize solar gain. Although, of course, the orientation of existing housing stock may seldom be changed, retrofitting steps can often require an improvement in high quality, thermally efficient triple glazing on the south side of the building.
Nonetheless, seasonal shading should also be considered in order to avoid overheating in summer. It can also be easily accomplished by using features such as extended eaves and well-positioned blinds, which minimize high-angle sun penetration without significantly affecting natural light amounts. Do you think I’m exaggerating?
Thermal Efficiency, Insulation and U Values for Eco-Friendly House Design
Have you ever asked what U value is?
well, it’s pretty simple, the design of any building requires close consideration not only of the external conditions of the site but also, of course, of the materials from which it’s made. Designs for more sustainable homes should first consider the carbon cost of materials before producing designs that allow those materials to be used to build homes that hold the heat in and need little energy to heat.
Let’s dig a bit deeper than that:
For example, environmentally friendly materials such as wood from sustainable forests, cob and straw can all be used as alternatives to other, more carbon-intensive materials in green buildings, including those built to meet the Passivhaus requirements.
The U value of the walls, roofs and floors defines the rate at which the heat escapes from the house. The lower the U value, the slower the heat dissipates. Passivhaus requirements allow U values to be no higher than 0.15 W / m2 for walls, roofs and floors and 0.80 W / m2 for individual windows, 0.85 W / m2 for completely mounted windows. For certain instances, the U values would be much smaller and are considered to be the highest acceptable U values. (In some situations, higher than is appropriate for building standards).
When you are retrofitting energy-efficient initiatives, external insulation might be better, because external insulation does not prevent walls from providing thermal mass (which helps to retain the heat of the sun and release it gently at night). It can also help reduce thermal bridges resulting in heat loss. It’s incredible, isn’t it?
Clever Airtight Design for Eco Homes
Another significant factor in the construction of energy-efficient houses is that they must have very high standards of airtightness. The airtight construction would further minimize the need for heating which can be done by means of barriers with membranes built-in to all elements of the building.
In addition, the airtightness achieved by the structure in Passivhaus certification is determined by the n50 test measurement. Air pressure checks are conducted, and air leakage at 50 Pascals pressure will be less than 0.6 changes per hour. Good design and execution of barriers are necessary if the strict requirements are to be met.
Smart Natural Ventilation & Heat Recovery systems for Eco Homes
It’s very important to consider the ventilation needs of the structure when implementing airtightness. Natural ventilation allows for the removal of excess temperature and safe and efficient flow of air by way of cross ventilation. This can be accomplished by knowing how air flows through a house.
The simple truth is that it is a condition of Passivhaus approval that a building does not experience temperatures above 25 degrees C for at least 10% of the year. During the summer months, natural ventilation can play a part in the maintenance of low-energy buildings, while in winter, natural ventilation can lead to undesirable heat losses.
Most notably, in order to further minimize heat losses while preserving indoor air quality, airtight designs also integrate mechanical ventilation and heat recovery (MVHR) into the designs. These systems operate by removing air from hot, wet spaces, such as bathrooms and kitchens, and moving it through a heat exchanger that transfers this energy to fresh air coming from outside. New, preheated air may be released back to the living areas of the house.
For Passivhaus approval, the heat recovery efficiency of the ventilation systems must be the same to or higher than 75% with a fan power equivalent to less than or on par with 0.45 Wh / m3 is necessary, and consideration should also be given to possible noise pollution and the transmission of sound between rooms.
Energy Efficiency and Energy Use In Eco-Friendly Homes
Effective insulation and solar orientation can help to build a home with low energy use, but homeowners must still take other steps to reduce energy usage. Select A+++ quality appliances and opt for high-efficiency lighting (such as LEDs).
Here’s the big idea: it could even be worth looking at photovoltaics and other means of local energy production to meet the low electricity requirements of the home. Practical solar steps can be taken in order to reduce the energy load of heating your water by preheating it insead. Water heating systems as well as heat losses incurred as a result of their installation may be the Achilles heel of the eco and Passivhaus design unless carefully considered at an early stage of the process.
What Is The Best Water, Drainage and Waste Management Practices for Eco-Friendly Homes?
Surprisingly enough, the use and control of water should be one of the main considerations for green-house design. Most eco-designs would implement water-saving measures such as low-flush plumbing and water recycling. Where appropriate, reuse of greywater and even disposal of wastewater in reed beds or other natural filtration systems is recommended.
Additionally, sustainable homes can also include composting toilets and other alternative waste management solutions. When you opt for the Passivhaus norm, the rules mean that you will take great care of ingress and discharge points for any pipes and heat that might be lost as a result of the construction of such water systems. Can you see where we’re going?
Waste management concerns also apply to the general household waste that will be produced in the home. The goal of zero waste at home would be to minimize the amount of waste produced as much as possible and to allow as much on-site recycling, composting and re-use of waste materials as possible.
Waste should also be considered during the building or renovation process. For sustainable construction and restoration, as much waste as possible will be removed from landfill sites. Of course, recycled materials can also be used where it is a good idea to do so. Consideration must also be given to the final disposal of materials used at the end of the building’s life.
Suitability, Liveability & Adaptability of Eco Homes
A genuinely sustainable dwelling house is one that is best tailored to its position and to those who live in it. I’m going to talk you through the whole process.
First of all, to ensure that the design of the home is designed to minimize energy usage and ensure year-round comfort, a bioclimatic map can be used to ensure that the designs are suitable for the climate conditions of the region. Such a map may also be used to assess the steps that are best used by any given house in order to increase its value and to reduce its current energy usage.
Designers can also use vector diagrams to assess the intensity and direction of sunlight at any one given time of day and time of year and to consider other factors such as wind direction and power, the effects of which can be mitigated with good design.
Liveability is also, very clearly, the secret to successful sustainable home design. The Passivhaus Regulations take into account the level of comfort needed for a healthy lifestyle in terms of heat and airflow. Light rates are also nice at home with passive solar design features, as much consideration is given about how rooms within the home are to be used and how they connect to each other.
Let me provide you with a couple of examples:
Main living areas, such as living rooms and dining rooms, will benefit from south-facing glazing, while the less glazed north side of a passive home will mostly be given over to rooms where light is less necessary, such as bathrooms, utility rooms and storage rooms.
In addition, adaptability is another element in sustainable home design. Sustainable homes must be constructed in order to be adaptable to several different circumstances. This adaptability is especially important in the face of our warming world and changing weather patterns that make forecasting far more difficult. By being largely self-contained and needing little external power to function effectively, a home with other sustainable and environmentally friendly features will withstand storms, both literally and metaphorically.
The Relationship Between An Eco-Friendly House & It’s Environment
Those who design sustainable and environmentally friendly housing will consider far more than just the energy usage of each house. In the sense of sustainable home design, it is important to note that no house exists in it’s own vacuum. It is important to view every home in the light of its environment. That sounds easy. No, it’s not.
A low carbon home will help the goal of a zero-carbon lifestyle. These may include features such as increasing space for food; storage space for bicycles and even additional features like workshops and home offices that will make it easier to operate and work in a flexible way from home. In a city or highly densely populated area, provision can be made for food production through green roofs, vertical gardens and container growing areas. These features can also be integrated into the insulation plans.
Successful sustainable design of a garden home will allow for an easy transition between the two and blurring the boundaries between the inside and the outside by incorporating features such as verandas and conservatories – both of which can be useful in different ways for passive solar design.
There are lots of tips and photos that you can use for construction ideas for your new eco-friendly home on pinterest where others who have succeeded in designing and building an eco-friendly home in the UK and other countries around the world have shared their success, send us your successful building projects or let us know your thoughts in the comments and we may just feature you in our next post. Alternatively, take a look at our other inspiring property posts, there may just be something there that could help you develop your dream home, renovation project or investment