There are roughly 20 million buildings in use in Germany alone – millions of properties that highlight so much potential to achieve our climate protection goals. The question is, where do we begin? Is there something every individual can do – in practical terms – to use or operate the buildings they own or occupy more sustainably? This is where the DGNB System for Buildings in Use comes in. We use nine criteria to focus the mind on all factors with a bearing on sustainability. In a series of blog posts, we describe why it makes sense for everyone with a stake in buildings to think more about these topics. In our first post, we look at the three criteria of buildings in use, which are relevant for the environment.

It’s one thing to erect buildings that are sustainable, a very good thing, but that’s only half the picture. It’s only when we use and operate buildings sustainably afterwards that we really make a lasting contribution to climate protection. Given climate warming, the big challenge is to achieve zero carbon emissions in the long term. So that makes things like drinking water and recyclable materials important when it comes to the environment.

Being carbon-neutral and systematically moving towards zero net emissions

As climate change marches on unabated it is becoming one of the central challenges of our time. Accordingly, reducing energy consumption and thus cutting carbon emissions should play a central role in how we use buildings. The DGNB System for Buildings in Use captures this important issue under its Climate Action and Energy criterion. If we’re really serious about combatting extreme climate change, we need to urgently stem carbon emissions, or to be more precise: reduce carbon emissions to zero. Our focus should clearly be to use carbon emissions as the benchmark. An important term here in this context is climate-neutral. But what does this all mean in practical terms?

The DGNB uses a specific definition for its approach to measuring carbon footprints. According to its definition, a building in use is climate-neutral if it produces the same or lower carbon emissions compared to the emissions it saves in producing carbon-free energy. Three factors are important in achieving this. One, overall energy requirements should be reduced. Two, ways should be found to produce energy efficiently on site. Three, energy should to be taken from sources resulting in the lowest possible carbon emissions.

This is where one has to be honest about systematically gauging energy use. Of course every building creates emissions, due to heating systems, air-conditioning units, hot water requirements and lighting. But thought also has to be put into other processes or systems used by buildings, such as transportation needs (how people or goods are moved around), IT use and how products are made. The idea of this criterion is to reward transparency when it comes to all forms of energy consumption, so that building owners implement continuous improvement processes.

A simple concept: simply start now

A number of pioneers in the industry are paving the way and showing how to operate carbon-neutral buildings. There are many different ways to approach this issue or mix and match ideas but if you get it right, all roads lead to Rome: roofs and facades with high-performance solar panels, homes equipped with high-efficiency household appliances, brine/water heat pumps for heating and air-conditioning buildings – to name but a few. It’s a fairly simple concept really: just get on with it! The journey you go on when becoming climate-neutral is not just about high-profile achievements or flagship projects, however. Even setting targets for carbon emissions, recording data, evaluating readings or drafting new action plans are a step in the right direction, which is why this is also rewarded with positive scores in the DGNB System for Buildings in Use. It is also why this criterion accounts for a significant share of the overall assessment score: 30 per cent. So if you have bold ambitions and want to fulfil them, you can already meet an important share of requirements under this criterion.

Drinking water: an increasingly scarce resource

A further precious resource, and one we often still take for granted in Germany, is drinking water. From a global perspective, drinking water will become a fundamental problem in the future, especially when it comes to climate warming. This makes it all the more important to start optimising how we use drinking water today. The aim of the Water criterion laid down under the DGNB System is to preserve natural water cycles and cut the amount of drinking water used by buildings in keeping with targets set specifically for individual projects.

This opens the door to a whole host of potential measures, especially if it forms part of a broader catalogue of measures. One way to reduce water consumption overall is to use different technology or equipment – e.g. fit different sink taps. You can also hang up graphs in places like reception to show usage levels and this may also have a positive impact on everyday consumption habits. The big difference in the long term is what you do with rainwater and grey water (from washbasins, washing machines etc). There are now different types of filtration technology that make it possible to almost completely close the water cycle by producing drinking water yourself. The principles are the same as they are for carbon emissions: start by setting goals, capture usage levels and then make optimisations step by step in any way that makes sense for a particular building.

Recyclable materials – more valuable than many realise

The third criterion of the DGNB System for buildings in use relevant with focus on the environment looks at waste management. When you operate a building, so many materials end up in the rubbish bin – from standard household waste to paper, biodegradable waste, metal, plastics and glass. These materials are often difficult to dismantle and may have been produced using finite materials, which completely runs against the grain of concepts such as the circular economy or cradle-to-cradle design. Under the Materials and Recycling criterion, positive acknowledgement is given to measures that improve recycling levels in buildings and reduce the amount of waste produced.

Again, systematic management tools are key. A pro-active approach to managing recyclable materials can include publicity initiatives such as posters, events, email campaigns, etc. Not only does this raise awareness, it also encourages people to think more consciously about their everyday behaviour. Incentive programmes can also help. And then there are ways to make it easier for staff to cut waste, such as providing drinks in returnable bottles. Introducing recycling facilities and different options to separate waste also allows staff to recycle more, which is why it is also rewarded during certification assessments.

Systematically preparing for the future

The DGNB System for Buildings in Use addresses all of these aspects. It provides useful orientation in focusing targets on tangible action and acts as an important tool in systematically changing and managing processes. As such, it’s also a helpful instrument when it comes to continuous improvement programmes. Click here for more detailed information on the DGNB System for Buildings in Use.

In our second post on this topic, we look at economic criteria. For a general overview of the topic, click here.