8% water saving boosts green credentials

Beth Werner

The environment weighs more heavily, so we need to think differently – and fortunately, says Claus Frydenlund, Property Technician at the Technical and Environmental Administration, City of Copenhagen


At the City of Copenhagen’s Technical and Environmental Administration’s central administration, Njalsgade 13-17, energy optimization and security has become something of an obsession – in a good way.

– That’s right, we are doing everything we can to reduce our energy consumption and thus protect the environment as much as possible. In addition, we protect both the property and its valuable archival materials against damage caused by e.g. leaks and cloudbursts, says Claus Frydenlund, one of the five property technicians in Njalsgade.

The central administration houses almost 950 employees and is spread over a total of 17,000 m2, including a customer center, building case and road and urban planning archives, library and office facilities. The property consists of three interconnected buildings with No 13 built in the 1930s, No 15 built in the 1970s and No 17 built in 1898.

In addition to securing Njalsgade 13-17 against water damage, both from inside and outside, sensors have been installed throughout the building complex that automatically turn off the lights when there is no movement in the building’s rooms. The green profile of the Technical and Environmental Administration is also manifested in the procurement of coffee, tea and raw materials for canteen food. It’s pretty much all organic.

Reduced water consumption by eight percent in 2016

On his way down to the property’s main technical room, located in the basement at no. 13, Claus Frydenlund explains that the seven DanTaet domestic water leakage protection systems installed in the main technical room last year alone saved the property almost 500 m3 in water consumption. – An eight percent reduction makes me happy for the environment.

Claus Frydenlund goes on to say that the main culprit for unnecessary water consumption is running toilets. We have a total of 100 of them, and with the high calcium content in the water here in Copenhagen, the valves are often clogged.

With the leak detection systems, we are alerted not only about the increased water consumption, but also in which of the three buildings the water consumption has exceeded the limit values. And this significantly limits the search when we have to go out and find the leak.

Liquid sensors secure over 100-year-old construction drawings

The customer center is located in No 13. On a typical day, the number of visitors, mainly citizens, easily reaches 60-70 people. – If you are rebuilding, extending or demolishing, it is very useful to know the exact location of piping systems or other structures in the building. Those drawings are in our archives, or rather archives.

We have two, a building case archive and a road and urban planning archive, Claus Frydenlund explains as we pass one large sliding shelf after another in the building case archive. All in all, 20 km of archives. The second archive is roughly the same size.

– The contents of the archives are incredibly valuable and I have the imagination to imagine what irreparable damage a burst water or heating pipe could cause. To guard against the worst-case scenario, we have installed a total of six Dantaet liquid sensors under the floors of the two archives.


The sensors detect even microscopic amounts of water that should not be there, says Claus Frydenlund, adding that the archives are currently being digitized. A time-consuming and extensive process that will take three to four years to complete.

Avoid water damage and save on insurance premiums

With a total of 15 DanTaet leak protection systems, eight for the heating system and seven for the water system, Njalsgade 13-17 is protected against water damage from the inside in the event of a burst water or heating pipe.

But also water damage from outside, e.g. as a result of cloudbursts are included in the protection plan for the property.

– We have had two or three cases of torrential rain with consequential costs running into millions. We would like to avoid them in the future. That’s why we have installed a cloudburst basin that can hold 90m3 water in one of our basements, and we have also installed cloudburst protection at the two basement staircases.

– The purpose of the comprehensive protection is, of course, to avoid any water damage. And secondly, we can get a nice discount on our insurance premium,” concludes Claus Frydenlund.

The central data unit in the main technical room collects and provides data from all leakage protection systems in the building. – It’s easy and clear that data is gathered in one place, says Claus Frydenlund.