Retrofit – 8 Steps to Success

Drew Barker
Posted August 25, 2023

We can’t talk about decarbonisation or net zero without talking about retrofit.

The UK government has a legally binding target to reach net zero by 2050, with an interim target to reduce emissions by 78% by 2035. Given that around 80% of the buildings we’ll be using in 2050 have already been built, constructing new homes is not enough. To achieve our national net zero targets, we must decarbonise the UK’s existing housing stock, we must do it now, and we must do it properly, because a bad retrofit can actually be a good deal worse than no retrofit.

Unfortunately, the UK’s housing stock is among the least energy efficient in Europe. Housing is responsible for almost a quarter of the UK’s carbon emissions. With the government committed to a 100% reduction in greenhouse gases by 2050 (compared to 1990 levels), it’s estimated that over 20 million homes will need to be retrofitted, at a rate of more than one per minute!

The many benefits of retrofitting

In addition to tackling climate change, retrofitting UK homes would have a big impact on the nation’s overall health, wealth and wellbeing. A deep retrofit can reduce energy bills, put an end to fuel poverty, make homes warmer, tackle damp and mould, and dramatically improve interior air quality. According to a recent report from the Building Research Establishment (BRE), improving England’s poorest housing could generate a whopping £135.5 billion in societal benefits over the next 30 years, including reduced carbon emissions.

Decarbonising 20 million homes would also improve the UK’s energy security and help to decouple our economy from fossil fuels. But it will require a small army of retrofitters. Some estimates suggest that a national retrofit programme could create up to 4 million new job opportunities.

What is the EnerPHit Standard?

EnerPHit is the Passivhaus standard for retrofits.

It allows for more wiggle room compared to the traditional Passivhaus standard, in order to accommodate retrofitting challenges. EnerPHit buildings are permitted to be a little less airtight (1.0 air changes per hour rather than 0.6ACH@50pa) with a space heating demand of 25kWh/m2/yr (instead of 15 kWh/m2/yr)*

The goal was to create a standard for an economically and ecologically optimal energy retrofit, for old buildings that cannot achieve Passivhaus standard with reasonable effort
The Passivhaus Institut

Rooted in the principles of Passivhaus, EnerPHit has been proven to deliver energy savings of up to 90%. And just like the traditional Passivhaus standard, EnerPHit has different classes – Classic, Premium, and Plus – according to the amount of renewable energy it generates.

Introducing the Beattie Passive TCosy Deep Retrofit System

The TCosy is our proprietary deep retrofit system.

As the name suggests, the TCosy works much like a tea cosy on a teapot. We wrap the entire building, creating a continuous void from foundations to roof, which is then injected with insulation to create an airtight envelope, with no thermal bridges. Triple-glazed windows are fitted, together with an MVHR system for healthy ventilation and heat recovery.

A deep retrofit involves upgrading the fabric of the building, the insulation, the heating and cooling systems and the glazing. We prefabricate the component parts of each TCosy under controlled factory conditions at our offsite facility in Norwich or in a ‘Flying Factory’ close to site.

Let’s take a look at the key steps and strategies involved in retrofitting homes to EnerPHit standard using the TCosy Deep Retrofit System.

Retrofit Step #1. Architect’s Concept

Every transformation begins with a vision.

Our architects and architectural technicians develop innovative concepts. Their creative ideas set the stage for a sustainable and energy efficient retrofit that looks as good as it performs.

Retrofit Step #2. Building & Energy Assessment

Rigorous building assessments are conducted to assess the energy consumption and identify inefficiencies. These assessments provide a blueprint for strategic improvements and help tailor retrofitting solutions to each building’s unique needs.

Retrofit Step #3. Beattie Passive 3D Designs

We create 3D designs in REVIT for visualisation purposes. These designs showcase the project’s potential, allowing stakeholders to make informed decisions, and allow us to precision engineer components.

Retrofit Step #4. Engagement with the Tenant

In our experience, a successful retrofit requires the active participation of tenants. Engaging with them and getting their support fosters trust, engagement and enthusiasm. With Beattie Passive, residents can remain in-situ for the entire duration of the retrofit – from start to finish.

Retrofit Step #5. Contractor Completes Retrofit

With plans in place, contractors set to work, transforming the leaky, damp and cold homes of the past into energy efficient, comfortable and sustainable homes that are fit for the future. You can choose to incorporate a source of renewable energy, such as photovoltaic (PV) panels.

Retrofit Step #6. Onsite Compliance Checks

Stringent compliance checks ensure that the retrofit meets the relevant standards. We use thermal imaging, and pressure tests to assess the performance of the building fabric.

Retrofit Step #7. Beattie Passive Testing & Certification

Thorough testing and certification verify the retrofit’s performance. Our assessments measure energy consumption, carbon emissions, and overall sustainability, providing evidence of the project’s success.

Retrofit Step #8. Completed Retrofit

The journey culminates with the completion of the retrofit.

Key benefits include:

  • Energy efficiency – up to 90% reduction in heating demand
  • An attendant decrease in carbon emissions
  • A new look home with a completely new external façade
  • An increase in the value of the property
  • Elimination of damp, mould and condensation
  • A healthier, warmer living environment

Closing thoughts

Each step in the 8-step retrofitting journey contributes to the goal of creating a more energy efficient and sustainable building. EnerPHit buildings are up to 90% more energy efficient, putting an end to fuel poverty and raising living standards for residents.

Don’t forget to take a look at our retrofit projects.

EnerPHit retrofit for social housing in Norfolk

Social housing retrofit in Solihull

Deep retrofit in Birmingham

EnerPHit standard retrofit and remodelling project

Private homeowner retrofit

* Note: Unlike Passivhaus, the heating demand for EnerPHit buildings varies with climate. The majority of the UK is still classified as cool temperate; however, cold and warm temperate locations can also be found in places.