An Architect’s Guide To Heat Networks

Heat networks are key to the UK’s decarbonisation of new-build homes and developments.  What do architects need to know about these future-proofed, low-carbon solutions as the Future Homes Standard becomes reality?

This article looks at how heat networks are setting the standard for the way heat and hot water are delivered into new homes and buildings across the country.

The integration of renewable energy delivery into a development is becoming a crucial consideration for architects as they forward plan for the UK’s continuing trajectory towards reducing reliance on fossil fuels. 

Heat networks stand to play a significant role in the country’s effort to reach net zero by 2050. To achieve such a deadline, we suggest any architect looking to contribute to the shape of current and future housing developments and commercial sites has a clear understanding of the technology, design parameters, sizing, installation and ongoing operation of these heating systems, that are beginning to replace gas networks.

A clear understanding of how a heat network operates both technically and in relation to the end users it is designed to serve will be instrumental in achieving success in delivery. It is also important for any specifier to realise that there is a choice of more than one type of heat network, allowing a degree of flexibility according to a site’s physical requirements.

Heat networks use a central plant to generate heat, which is then distributed through a network of highly insulated pipes to multiple buildings or units.  The design of these pipes should consider the layout of the development, heat losses from the pipes, while ensuring the network can handle the required flow rates and temperatures for efficient heating and hot water delivery.

Architects should aim to understand how the heat network will interact with the building design. Building layout and zoning are key parameters for architects when considering heat networks.

Architects should aim to design buildings in a way that allows for easy connection to the central heating plant, ensuring that heat distribution is even and efficient, and that piping can be routed to all necessary areas. Intelligent zoning of heating requirements can reduce the energy load on the system.

If an architect specifies a central heat hub, for example, allocation of sufficient space for the plant and distribution system is crucial.  Positioning the central heat generation plant as unobtrusively and as effectively as possible in relation to the site it serves along with everything that is contained within the centralised hub, is of considerable importance to the success of the whole. Its site location should be an early decision in the planning of a development.

Integrating the design of heat delivery into homes and buildings also requires careful consideration. Each home or building needs to have space allocated for a heat interface unit, which controls the heat and hot water delivery within each building. These can often be installed in utility rooms or plant rooms in individual units.

The heating system within each building should be designed to integrate with the heat network efficiently, a compatibility which includes the design of radiators, underfloor heating, or other heat delivery methods.  The location of controls, such as smart thermostats, should also be considered to ensure that residents can manage their heating and hot water consumption effectively.

For accurate specification, architects should be aware of the temperature and pressure requirements of the heat network, ensuring that the design of any building’s systems, particularly the distribution piping and radiators, can handle these levels. Typically, heat networks operate at lower temperatures than traditional gas heating, which may influence the choice of internal heating solutions. High-efficiency design should be prioritised, meaning that the temperature of the heat network should match the building’s needs.

A key consideration for architects is ensuring the development has enough heating capacity. This requires collaboration with engineers to estimate the heat demand for the entire site, considering factors like the size of the development, the insulation standards of the buildings, occupancy levels and usage patterns, and external temperature variations.

Engineers typically perform detailed heat-load calculations to determine the capacity of the central plant, as well as the size of pipes and heat exchangers. The architect should ensure the design specification allows for this load distribution. 

Heat networks are an excellent way to integrate renewable energy into a development. Architects should consider the following:

Heat networks must comply with national and local building regulations, particularly with respect to energy efficiency, carbon reduction, and safety. In the UK, this means compliance with Part L (Conservation of Fuel and Power) and Part G (Sanitation and Hot Water), which govern how heating and hot water systems are designed and installed.

Some local authorities may have specific requirements for heat network plans. Architects will work closely with the planning authorities to ensure that the heat network aligns with local energy strategies, to gain the requisite approval.

A heat-network design should allow for easy access to the central heat plant, pipes, and other infrastructure for maintenance and inspections. This might involve designing dedicated plant rooms, service ducts, and clear paths for accessing key equipment.

So it is that architects should consider a wide range of factors when integrating heat networks into the design of new-build developments. They should work closely with engineers to ensure that the size, layout, and integration of the heat network are efficient, sustainable, and well-coordinated with the overall building design. Key factors such as space planning, energy efficiency, regulatory compliance, and future scalability must be carefully addressed to ensure that the heating system is effective, reliable, and future proof. Moreover, the building envelope and the comfort of the occupants should always be considered in the design to ensure the system operates efficiently and meets both environmental and user needs.

Read more on our Networked Ground Source Heat Pumps.

Read more about our Community Heat Hubs.