The Green Homes Grant must not be a wasted opportunity

If the government’s £5bn Green Homes Grant is to be successful, lessons must be learnt from the Green Deal, say Enhabit’s Dr Sarah Price and Akta Raja

Sarah Price

Akta Raja

After the failure of the Green Deal and the string of unintended consequences related to Energy Company Obligation (ECO) projects, are we finally going to get the kick-start the industry so desperately needs? 

Done well, the government’s new Green Homes Grant could result in new jobs, upskilling of the workforce, healthier buildings, recurrent carbon savings – and a consumer who understands that buildings can perform better. Another failure, and we will lose the confidence of the consumer completely, carbon will become locked-in, investments won’t be made – and we will have missed a massive opportunity.

The architecture of the Green Homes Grant must avoid the performance gap and allow consumers to understand the benefits of retrofitting: lower carbon, high comfort, and lower running costs. If this is achieved, the market will start to understand the real benefits of retrofit, and it will become more widely adopted, the industry will grow, and taxpayers’ money will be well spent.

Performance gap
The causes of the performance gap are well known. For example:

  • Applying insulation without appropriate ventilation has led to mould growth and poor indoor air quality
  • Installing modern vapour-impermeable insulations to older buildings has led to trapped moisture, interstitial condensation, and degradation of the building fabric
  • Neglecting airtightness has led to excess heat loss, thermal discomfort, interstitial condensation, and poor insulation performance
  • Poor building surveys and ignoring remedial works has led to trapped moisture and degradation of the building fabric
  • Poor quality control in design and construction leads to moisture ingress, excess heat loss, thermal discomfort, and structural and fire safety compromises.

While the government has yet to release full details, there are early signs that it may have finally paid attention to the experts and embraced the right way of retrofitting, by making sure that the Green Homes Grant will only become available if the work complies with PAS 2025: 2019 ‘Retrofitting dwellings for improved energy efficiency. Specification and guidance’. Compliance with PAS2035 will become mandatory for all ECO projects from 1 July 2021, so it makes sense for the Green Homes Grant to make use of the regime.

Under the scheme, the retrofit coordinator oversees the process and protects the interests of the client and the public. The PAS defines the levels of competencies required for other roles, including retrofit designers, assessors, advisers, installers and evaluators for different levels of retrofit, and recognises a whole-house retrofit should be treated in the same way as a new-build project.

Retrofit coordinators
Using retrofit coordinators will reduce the risk of damage to the building’s fabric and shrink the performance gap – and may also be a way of protecting the consumer against the cowboys who appeared solely to take advantage of the Green Deal, ECO and free cavity wall insulation schemes.

Retrofit coordinators are not a panacea; ultimately, the training is only six days long and only a few hundred people have completed the course. The real test will be of the regulating body TrustMark, to see if it can maintain the quality required for retrofit. Retrofit projects are going to require the best building physics and engineering minds, so it’s also important for engineering bodies such as CIBSE to ensure that they provide the right support and guidance for all types of retrofit. But it also needs the entire industry to work together.

The wide range of industry bodies needs a coordinated response to the grant; engineers and architects need to work closely with manufacturers, distributors, contractors and project managers. Together, we are powerful and can make a meaningful impact on how the policy is implemented, and ensure that there’s not just a race to the bottom. Individually, we are too disparate to achieve that level of impact.   

Ultimately, the Green Homes Grant is just the tip of the iceberg – an average of £5,000 per home will not be sufficient to deliver the depth of retrofit required to meet zero carbon targets by 2050. Also, the £2bn pledged will provide some retrofit measures to around 400,000 homes – a tiny fraction of the 24 million housing stock that will need retrofitting by 2050. So let’s hope this is just the start.

About the author
Dr Sarah Price is head of building physics at Enhabit and Akta Raja is founder of Enhabit