Heating and Ventilating

The Government wants the industry to deliver quicker build times; lower lifecycle costs; and less energy demand. How can the commercial heating sector play its part and what supply chain changes will be necessary to make it possible? James Parkinson explains.
Chief Construction Adviser Paul Morrell has made it clear that the UK faces its biggest rebuilding challenge since the Second World War. In fact, CIBSE President Andy Ford suggested we might need to create something similar to the National College for heating, ventilating and air conditioning that was developed after the war to ensure we had the skills and depth of labour pool to meet the vast potential workload.

Today the nature of the challenge is different - we are aiming to cut our carbon footprint by 80 per cent over the next 40 years - but the scale is almost identical. Mr Morrell described it in terms of refurbishing one building every minute between now and 2050 to reach our energy efficiency and carbon reduction targets.

24 million buildings, expected to still be in use in 2050, are already built including 60 per cent of the commercial stock. 13 per cent of the country's entire CO₂ emissions come from commercial buildings. That presents a truly gigantic refurbishment challenge.

We are moving into a completely new phase for our industry. Commercial heating has an enormous role to play in the programme needed to bring existing buildings up to standard and equipment manufacturers will need to be involved much earlier in the process to ensure the technology slots easily into the project process. Consulting engineers are already relying more heavily on specific technology experts to ensure the technical details are right from the outset.

However, we will all have to learn new tricks as well. We have always been pretty good at designing new buildings and new systems, but retrofitting millions of old buildings poses a whole new set of challenges.

First, we need to know how the building is performing - you can't save energy if you can't measure it and work out where it's going. Therefore, installing sensors throughout a building is a useful first step and the wider use of smart meters will also help. Increasing the use of Display Energy Certificates (DECs), as being advocated by the UK Green Building Council, would also be a really positive step towards making sure the energy information we have about building systems is up-to-date and meaningful.

Before setting about replacing or upgrading services, the refurbishment team must look at potential 'fabric' improvements, such as insulation, draught proofing and glazing. This will have an immediate impact on energy demand. The next step should be to examine what controls are in the building, how they are set up and if they are easy to use.

If we improve the fabric, we will end up with a more airtight building and this means we need to ventilate it. This should create a demand for mechanical ventilation systems with heat recovery. These systems capture and reuse heat that would otherwise be wasted, reducing the heating demand and offsetting the energy impact of the ventilation fans.

Tackling the thermal efficiency of the building in this way means specifiers can look at smaller capacity, and therefore less expensive, heating and air conditioning systems as part of an upgrade. Existing boilers, chillers, ventilation plant and lighting systems can also be re-commissioned to improve their performance.

Boilers will continue to play a vital role for years to come and upgrading or replacing the 'heart' of the heating system is the logical place to start, for many energy efficiency refurbishments, because it will deliver quick and cost-effective results. However, to maximise the benefits we must all work in a more integrated way.

The traditional industry supply chain is very linear and hierarchical, and that is no longer fit for purpose if we are to deliver a national refurbishment programme. We need a much more team-based structure where technology experts are involved right at the outset to confirm which technical solutions will work in the specific conditions of the building in question.

We need to be sharing energy performance data with everyone involved from the very beginning, including close analysis of where the building is failing to reach its targets. The emergence of sophisticated tools like Building Information Modelling (BIM) means all team members can share dynamic information from Day One - and then carry that information forward together through the project process.

Intelligent modelling

A big motivation for using intelligent modelling is to produce buildings that operate closer to the design intent of the engineering team. 3D visualisations dramatically reduce the number of clashes in a building design so speeding up delivery of a building services project, cutting costs and improving the on-going performance of the building - this could be crucial in a refurbishment scheme.

However, it also depends on good commissioning so the expert team needs to remain together right to the end and then on past handover. Measurement of the building's performance once the building is handed back to its occupants can also be carried out more readily using the model created in BIM, but also supplemented by information from the DEC. This should also become part of our contractual commitments to the client to ensure the building continues to meet its energy targets in the long-term.

Reform of the supply chain is almost as important as the many low carbon solutions we, in the heating industry, are producing. The size of the refurbishment programme gives us an opportunity to build teams with complementary skills and keep them together on multiple projects.

This means we can build up a bank of knowledge that can be reused time and again as this massive programme of work is rolled out. However, if we attempt this task working in the old, hierarchical way we will simply not make it.

• James Parkinson is the marketing director for Ideal Commercial Heating