Kynance

The Project

We were approached by an existing contractor to design a heating system for a bespoke new build in South Gloucestershire, a 350m2 property with a requirement for underfloor heating, MVHR, hot and cold water supplies and a Ground Source Heat Pump system as well as a large separate garage needing to be heated and cooled.

The client was keen to build an energy efficient home, making use of the garden available for a ground loop and using the timber frame home to install underfloor heating throughout. We looked to design a full package that would suit the customer’s needs, including allowing for a passive cooling system through the MVHR and ground source heat pump

The Solution

The property boasted high insulation values throughout thanks to the timber frame, thick floor insulation and insulated roof spaces.The total heat loss for the property came to 15kW, with a 15kW Vaillant Flexotherm ground source heat pump selected to heat the house. Cliptrack and screed underfloor heating was designed for the ground floor with aluminium clippaplates used for the first floor between the eco joists.

For the MVHR system we used a semi rigid 63mm ducting to provide the supply and extracts to each rooms as required, these then connected to a Domus MVHR unit sized for the property and providing fresh air to each room with an automatic summer bypass to prevent the house over heating.

The ground source heat pump was designed alongside a 300 litre cylinder and 200 litre buffer vessel, the Vaillant Flexotherm comes with a passive cooling option to allow the heat pump to supply cooling in the summer months through the ground loop. This ground loop needed to be a borehole due to the lack of space for a horizontal loop, 2 x 150m boreholes where dug and filled with 20mm flow & return pipework and backfilled with a high thermal conductivity grout.

As for the garage, we installed a Daikin multisplit system with 4 wall mounts for the garage, workshop and the office space above. This provided a simple, cost effective solution for heating whilst also offering cooling and a constant environment for the customers car collection!

The Installation

As with most new build projects this one was completed over several months, this the underfloor heating and first fix plumbing and MVHR taking priority. Space was a premium on this project and fitting the MVHR alongside all of the plumbing and electric work was no mean feat as the customer wanted to maximise room space.

The boreholes were completed by a 3rd party with us connecting onto a manifold before taking the main flow and return back to the plant room. We worked alongside the electrical contractor and second fix bathroom fitters to ensure a smooth installation and make sure all locations were correct.

The Results

The resulting home is one that is cost effective to run and comfortable to live in all year round. The underfloor heating throughout provides constant heat and the MVHR is able to provide cooling in the hotter summer months with free cooling from the heat pump. Although the customer was not eligible for any grants the installer should result in a cost saving of 60% when compared to alternative heat source such as gas or oil.