Achieving Passivhaus performance with Durisol

Achieving Passivhaus energy performance is easily possible when incorporating an insulated high thermal mass Durisol frame with a smart automated control system, a recent research report reveals.

The year-long study was conducted by Atamate, emerging market leaders in smart building technology who set out to determine if Atamate building controls can outperform traditional systems and save on energy. They used a Durisol new-build to test the theory.

They found that heating energy demand was cut by an average of 34% below standard assessment procedure (SAP) predictions, and exceeded Passivhaus standards even though construction was not expensive, as is often the case when striving to meet Passivhaus requirements.

Achieving Passivhaus performance

Atamate demolished two Victorian terraced houses in Cogan Terrace, Cardiff and replaced them with six new flats built with Durisol ICF.

Achieving Passivhaus performance-demolish houses

Achieving Passivhaus performance-build with Durisol

Each flat was fitted with DCVi (Demand Controlled Ventilation Inlets) comprising 100mm vent pipes drilled through the wall of all “dry rooms” (bedrooms and living rooms). Medium response electric panels heaters were installed for heating.

The buildings were fitted with the Atamate building control system which has sensors that monitor air quality for ventilation purposes, and room occupancy for heating purposes. The sensors enable dynamic control of the heating and ventilation to maintain an optimum environment for all occupants without the need for human intervention.

The study

Once the flats were complete, the buildings’ performance was measured for 12 months (from mid-September 2017 to mid-September 2018). Incidentally, this period included the “Beast from the East” 2017 winter storms and the sustained summer heatwave of 2018.

The results

The results of the study are striking.

The Passivhaus standard sets a threshold heat energy demand per unit area of just 15 kWh/m2/yr. The actual average heat energy demand of the six flats was measured was only 12.48 kWh/m2/yr.

Four of the six flats easily outperformed the standard (with the lowest reading a tiny 5.26 kWh/m2/yr) with only the two ground floor flats falling just short of the standard. The ground floor flats have doors opening to an unheated communal corridor which could explain the difference. Regardless, the results are impressively close for a building not designed to Passivhaus recommendations.


This study demonstrates that combining modern methods of construction, which are quicker and more economical, with small automated heating and ventilation systems provides many benefits, namely:

  • Upfront capital savings compared to traditional fabric build methods and large wet heating and ventilation systems.
  • Enhanced performance and lower energy demand.
  • The possibility of creating low carbon homes at a price point that would incentivise widespread rollout.

It’s not possible to derive from this study how much of the performance we can attribute to the Durisol frame compared to the smart automated control system.

However, what is clear is the low energy demand that’s possible when combining the two systems.

You can read the full report here.

For more information on building with Durisol, please call us on 01495 249400 or email us.