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Affordable zero energy buildings

Periodic Reporting for period 2 - A-ZEB (Affordable zero energy buildings)

Reporting period: 2018-11-01 to 2020-04-30

In order to address our ecological and climatic challenges as a society, we need to improve the energy performance of our buildings towards (nearly) zero energy. Europe has posed the Energy Performance Buildings Directive (EPBD) which requires all new buildings to be Nearly Zero Energy Buildings (nZEB) from the year 2020 onwards. However, progress is slower than expected. One of the reasons for this is that nZEBs are perceived by the market and by the building sector to be more expensive than conventional buildings.

The AZEB project is a coordination and support project which intends to increase the uptake of nZEB in the market. This should lead to the building of more nZEBs, more primary energy saved, increased investments in nZEB's and more (local) renewable energy production. AZEB stands for "Affordable Zero Energy Buildings".

The AZEB project had three main objectives:

Objective 1. To develop an integrated methodology to achieve affordable (nearly) zero energy buildings.

A 17 step methodology was created which integrates multiple fields of solutions (both technical and non-technical) and the complete project lifecycle. It is based on existing solutions, which are integrated into a coherent framework. The effectiveness of this methodology was shown in case studies during the project.

Objective 2. To disseminate this knowledge as market-ready solutions to the widest possible EU-audience and inspire these stakeholders to take up and improve new nZEBs with RES concepts and implement the cost effective solutions.

In the project the methodology was translated into target-group oriented educational material, which allows for online learning as well as on-site learning, to apply the methodology in current and future projects. Also several tools were developed to aid stakeholders in the implementation of the methodology.

Objective 3. To facilitate frontrunners and innovators, from policy-makers to progressive contractors, and this way help them transform the building sector ito a sustainable industry.

Many of our educational and promotional products will be available for use for these frontrunners and innovators to help them bring their arguments across to their target audiences. The material was actively disseminated to this frontrunner target group and stimulated the use of our material. It is available trhough In the coming years further development and exploitation of the AZEB materials has been planned by several of the project partners.
In the first eightteen months of the project a first version has been developed of an integrated methodology to achieve affordable (nearly) zero energy buildings. The methodology starts with clear explanations of different indicators for a cost-effective nZEB. Then it integrates technical and process oriented solutions to reduce costs throughout the complete lifecycle of the project, it contains solutions to stimulate investors to invest in higher initial costs by guaranteeing lower lifecycle costs and it contains solutions to concretely demonstrate to the client or user what the actual added value of the building is in relation to the initial costs. This added value can be environmentally or socially or economically, e.g. in lowered operational costs. The methodology also contains solutions to aid in better decision making by facilitating good trade-offs between possible solutions.

1. The AZEB methodology, which consists of 17 consecutive steps, spanning the different phases of a building project: initiative phase, design phase, construction phase, operational and use phase.
2. A free e-learning course for professionals containing lessons to understand how to use the AZEB methodology as well as many materials to facilitate application (
3. Five excel based tools for better decision making on sizing and performance of nZEB components
4. The excel based AZEB TCO tool: for aiding in decision making by showing the impact of specific technical or non-technical decisions on the total costs of ownership as well as on social indicators such as comfort and health
5. An upgrade of a dynamic simulation tool for optimizing nZEB designs for cost and environmental impact
6. A guideline for creating whole building nZEB performance guarantees
7. A workbook for clients, guiding them on how to apply the AZEB methodology from a client perspective.
8. Several general and specialized AZEB classroom trainings for which the manuals are freely available.

Most materials, including the methodology, have been published under the Creative Commons license, with exception of e.g. the software tools.

The coming years these results will be used by the AZEB partners and some associated educational institutes for:
* providing training and courses on AZEB topics
* further research on the impact of applying AZEB method in actual projects
* consultancy work for nZEBs
* further improving of the method

Five case studies were done to demonstrate the impact of the application of parts of the methodology to stakeholders. The case studies lead to further improvement and simplification of the methodology into the current version. Also they showed the potential impact of applying the methodology on lifecycle costs, on environmental impact and on social impact.
Our expected direct impact, during the project, was to reach at least 1720 experts who are then able to practically apply (parts of) the AZEB methodology. We have reached over 2500 in live or online events. Also we have engaged in the final stage of the project several educational institutes to adopt the AZEB material and use it when teaching or doing research.

Our expected indirect impact during and after our project, by applying (parts of) the methodology in building projects is:
- reduced primary energy consumption of nZEB buildings
- reduced costs of nZEB building projects
- higher renewable energy production

In addition to this, we expect that buildings that have been developed using the AZEB methodology will overall have higher value for the user/owner: better performance in lifecyclecosts, building value and occupancy rates, better performance in social indicators like comfort and health and better performance concerning environmental impact. For our society this should lead to a better built environment, a more conscious building sector and more conscious users, both making better decisions in relation to the ecological and climatic challenges we face. A questionnaire with 50 respondents showed that:
* a large proportion was keen to use it or had already used the method, most benefits were perceived for the early project phases, complexity was rated as medium, significant cost savings had been achieved or were expected by applying the methodology, as well as significant energy savings. Also a large proportion of the respondents expected additional value creation for social indicators, environmental impacts, real estate value and client satisfaction.
17 step AZEB roadmap