Passive House Foundations
Our PassivHaus Certified Foundation systems deliver the best U-values (0.107) on the market with a Zero Cold Bridge effect between the wall and the floor. Our foundations are built using structural Polystyrene (EPS) engineered to take loads of up to 350kn/m making it an excellent choice for both timber frame and Poroton block built Passive Houses. EPS 300 can take loads of up to 300Kn/m2 which is about 30 tonne/m2 but we put on a maximum load of 150Kn/m2 for safety reasons.
The house sits on a reinforced insulated ring beam with an insulation upstand dividing the ring beam and the concrete floor. Swedish tests show that 65% of the heat from UF heating is lost to the ground when a standard Irish foundation system is used, our system reduces the heatloss to 17%.
Our Patented G element is used for heavier loads and can take loads up to 350kn/m (35 tonnes/linear metre). Heavy internal loads can be easily taken by thickening the slab and putting EPS 300 under the floor at this point.
We calculated the heatloss from traditional Irish foundations using DEAP. The floor was designed to have a U-value of 0.25 but when the Cold Bridging at the perimeter walls and where the internal walls sit directly on the ground were added the real U-value jumped to 0.47. When we calculate the heatloss at the front and rear door treshold and where the chimneys sit directly on the ground the actual U-value of the floor went up over 0.60.
Irish houses tested with our Thermal Imaging camera showed up red around foundation level due to major heat loss at this point. When building a Passive house it's important to start with good foundations. There is a cold bridge in every Irish house where the foundations meet the walls because there is a break in the insulation and the inside block sits directly on top of the Cold foundations causing major heat loss. If we built a Passive house on top of standard Irish foundations most of the heat loss would occur at this point. We never use Polyurethane (Kingspan, Quinntherm) in wet areas under concrete floors in our foundations because Polyeurethene loses its U-value when it gets wet. Putting in layers of plastic below and above the insulation traps condensation from the concrete drying out.
Viking G foundation element with a Quinnlite internal leaf, a 200mm cavity filled with EPS Platinum bead and a concrete block external leaf. You can see how easy it is to run the Radon Barrier with our system, this is the major fault with our competitors!
Viking Double L foundation element with a Timber Frame wall and a concrete block external leaf. You can see how easy it is to run the Radon Barrier with our system, this is the major fault with our competitors!
See how we can build our foundations in a week.
Strip the topsoil until you meet good soil and top up with compacted 18-35mm hardcore compacted in 50mm layers.
Mark out the corners with wood profiles/string and install the corner foundation sections.
Fit the intermediate sections.
Place the first and second layers of Insulation material on the compacted hardcore and roll out the Radon barrier.
Install the third layer of insulation on top of the Radon Barrier.
Push 5mm Stainless Steel ties through the polystyrene to connect the ring beam to the slab and place steel rebar's of the specified size in the ringbeam.
Place UF heating pipes on 6mm steel mesh or on special shoes under the mesh.
Pour the 10cm concrete slab and ring beam in one pour. Let it rest for the weekend and start building your walls on Monday.
