April 20, 2024


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Energy certification of buildings in the UK

Energy Performance Certificate (EPC) - Energy Legislation Hub

The United Kingdom is one of the European Union countries that previously imposed the energy certification process, in 1995. (Energy Rating). Its regulations are applicable to existing homes and new constructions.

The classification in this country is called SAP (The Standard Assessment Procedure), and ranges from 1, which corresponds to the lowest energy quality, to 100. It is considered a high energy quality, from a classification of 80. Check the SAP Calculations for extensions cost here.

The SAP is used to comply with building regulations that, according to current legislation, require an energy index in any home. The standard evaluation procedure generally reflects the theoretical annual energy costs per unit of space, as well as the expected costs of heating, which makes sense according to British climatology.

It consists of a static balance of the energy demand of a home, which results in CO2 emissions per year.

The energy certification processes are carried out by professionals who have received training in this matter and have had to pass an exam that allows them to carry out this type of process.

CO2 emissions are calculated based on the calculation of the TER (Target Emission Rate), which is the index of CO2 emissions of the target dwelling with respect to the reference dwelling, and is expressed in [kg of CO2 per m2 of surface per anus].

This classification does not assess the location of the building, its weather, or consumption of lighting and electrical appliances.

To evaluate energy demand, the following variables must be considered: heating, hot water, lighting and energy used in pumps and fans.

A rating is given regarding its energy performance and its impact on the environment.

Finally, low-cost recommendations, less than 500 pounds and higher-cost ones, are provided to improve efficiency standards.

Sustainability: energy standards, qualification and certification of buildings, and software

How is the sustainability of the building construction process measured? What does the concept of sustainable development imply? This term was used for the first time in 1987 in the Brundtland Report -titled Our common future-,  which was developed by different nations of the UN, and directed by the former Norwegian Prime Minister Gro Harlem Brundtland. In it, the high environmental cost implied by the current economic and social model was explained , and it defined  sustainable development as one that satisfies current needs, without compromising those of future generations.. We can transfer this same concept to the building process, analyzing how to design, construct, rehabilitate and even demolish buildings, and contrasting their impact on environmental sustainability.

What is sustainable development?

The general concept of sustainable development began to be used in the 70s, even with other meanings such as eco-development, sustainable development, sustainable growth, etc … and refers to the need to search for economic progress, without harming it. to the quality of life or the environment . It also implies a moral commitment that has to do with future generations. In short, it consists of a growth model, which affects the economic, social and ecological systemand that has to do with the economy, consumption, planned obsolescence, building, the growth of cities, education, politics, the use of fossil fuels such as oil, the use of renewable energy sources such as wind, photovoltaic or solar thermal, CO2 emissions into the atmosphere, global warming, waste generation, etc.

To measure sustainability, first of all, a series of sustainable guidelines and a series of indicators must be defined, that measure and report that the current development process is really positive or negative in reference to what we understand as sustainable development, and it is not an easy task, since it can be an ambiguous and even empty concept, if the way to carry it out is not specified, nor its content.

How can you design, build and even rehabilitate buildings in a sustainable way?

Next, we are going to extend the concept of sustainability to buildings, that is, to the activity of designing, constructing and rehabilitating buildings. According to the ihobe report, the building construction activity must consider and analyze its impact on the three aspects on which sustainable development is based, also known as Triple Bottom Line (TBL): the environmental, economic and social aspects.

This report specifies a series of considerations that have to do with:

1. The functionality of the building.  They have to be durable buildings that work and are accessible, that guarantee thermal, acoustic and light comfort, and that are healthy for their users. They also have to be aesthetically pleasing, taking into account their integration into the environment.

2. Efficiency in the use of available resources:

– Energy . They must have a good thermal behavior in their interaction with the environment, so that they only consume the energy it needs; Furthermore, said energy must be fundamentally from renewable energy sources.

– Water . They should promote the responsible consumption of water by users, as well as the use of rainwater and the proper management of wastewater.

– The materials used and the waste generated. It also has to be designed and built with environmentally friendly materials that can later be recovered, reused or recycled, and whose content is not dangerous. The management of existing hazardous waste must be done in a responsible manner.

3. Respectful of the environment. They must be integrated into their environment, according to the local culture and heritage.

4. Economically competitive. They must consider the complete life cycle from an economic point of view, assessing the cost of construction, maintenance, useful life, resale and end of life.

Concepts, movements and building evaluation systems that have to do with sustainability

Bio-construction or eco-construction

It is a type of chemical-free construction that has to do with traditional construction. It uses easily obtained materials, that is, low energy consumption for its manufacture and therefore with little environmental impact; as well as recycled and easily recycled materials.


Bioclimatism takes into account the climatic conditions of the place to design and construct the building: the use of solar radiation and darkening through architectural elements that cast shade, or through vegetation; the use of wind and solar orientation, of pressure and temperature differences, etc. The objective is to control energy behavior in its energy exchange with the environment, reducing energy needs . For this, the correct design of the building is essential: the appropriate geometry and orientation of each element, as well as the choice of materials, their thermal inertia, conductivity, etc. and the effective use of available bioclimatic strategies.