Ecomerchant work closely with the Rationel team, helping with the detailing and specification of the Rationel range of passive suitable windows.
We are able to offer the passive suitable windows at amazingly competitive prices due to volume sales and the innovative design developed by Rationel. They have taken a fresh look at the science of passive design and been able to offer an outward opening simple timber or ali clad timber frame without the complex multi layering of insulation and wood normally associated with Passive House projects.
Rationel have focused on the energy balance key by calculating, accurately, which glass type should be used in which elevation to balance heat gain and heat loss. It’s not necessarily the lowest U value windows that save the most energy as they can significantly reduce the benefits of some solar heat gain. In addition the detailing of the insulation within the window reveal is important to reduce losses through the frame, but the slender frame sections improve the overall glass to frame ratio thereby reducing the impact of the frame on the overall calculations. To find out more about windows for Passive House projects contact the Ecomerchant joinery team on 01795 530130 and if you are an architect book a free tech visit.