Nudura’s Insulated Concrete Formwork (ICF) system was selected for the rebuilding of an existing cottage to Passivhaus standards in an Area of Outstanding Natural Beauty.
The client’s brief for The Curly House was to design and build a dynamic, contemporary 407.8m2 home that would minimise their energy consumption and carbon footprint.
Architects Ecotecture designed a crescent shaped detached building which steps into the slopes of the site and features a curved brise soleil.
After considering a raft of sustainable construction options, Nudura ICF was specified for the walls and OP-Deck (thermally broken super insulated deck system) for the floors and roof.
ICFs are highly suited for ease of build with complex structures and the same system can be used for below and above grade walls.
The Op-Deck was specified to take a load of 5kN/m2, the heavier construction option was chosen to provide thermal mass and balance the heating gains and losses due to the large areas of glazing.
The insulating element of Nudura’s ICF acts as a buffer to the thermal mass allowing the slow release of heat into the building to ensure a constant internal temperature throughout the year.
Reinforcement in the building was provided by vertical and horizontal rebar, lintels were designed to be poured in situ and made up of rebar saddles.
By combining Nudura ICF and OP-Deck it was possible to reduce thermal bridging to a minimum.
It allowed the brise au soleil main support system to be bolted back to the concrete core and the thermal bridge was further reduced by using stainless steel anchors.
By using ICF and detailed construction, the building has surpassed the air tightness standard required for Passivhaus compliance.
During their first winter the homeowners of Curly House didn’t need to switch their heating on throughout the winter of 2011/2012.