What is retrofit?

Retrofitting - making changes to your home to increase energy efficiency - is a great way to lower your utility bills. Reducing our energy consumption is also crucial in addressing the climate crisis.

Retrofit measures such as roof insulation, solar panels and smart meters can all result in energy savings

3.1 Why retrofit?

Undertaking retrofit measures can result in significant savings in energy bills. If you are considering building an extension or making a home alteration, this is an ideal time to also integrate retrofit measures in your home.

Homes are the single biggest contributor to carbon emissions in the UK. Around 70% of homes in Waltham Forest were built before 1944. Much of this housing is energy inefficient, meaning houses tend to be harder to keep warm and reliant on fossil fuels rather than renewable energy.

Retrofitting our existing housing stock to a high standard is key to limiting our contribution to global heating and playing our part in tackling the Climate Emergency.

A high quality retrofit approach to extensions and alterations can have the following benefits:

• Lower energy bills by increasing energy efficiency, reducing the need for heating.
• Comfortable homes that remain at a pleasant temperature, and do not get draughty or damp.
• Improved health as damp and cold interiors can lead to a range of health problems, including asthma and allergies, and contribute to poor mental health.
• Reduced carbon footprint through reduced dependency on fossil fuels and lower energy use.
• Higher property value by increasing a home’s EPC rating.
• Reduced noise for occupants through enhanced insulation and improved glazing.

Benefits of retrofitting include making your home more comfortable and saving you money over time, once initial costs are recouped3.2 Retrofit measures

If you are extending or altering your home, there are retrofit measures that could be carried out at the same time.

The following retrofit measures are covered in detail later in this document:

• Internal insulation can be fitted within lofts, walls and underfloor cavities to improve thermal performance.
• External wall insulation can be fitted to the outside of solid external walls.
• Glazing upgrades to windows and doors can prevent draughts and reduce heat loss.
• Air source heat pumps (ASHPs) can serve as a more efficient alternative to gas boilers.
• Mechanical ventilation with heat recovery (MVHR) provides a way to ventilate the home while retaining heat.
• Underfloor heating serves as a more efficient alternative to radiators for heating the home.
• Solar panels can generate renewable energy for the home.
• Battery storage enables more energy to be kept and used within your home.

There are also a number of alterations you can make to your garden, which can help the environment by supporting local biodiversity and mitigating surface water flooding.

These retrofit measures can be combined with other smaller interventions to increase the comfort and energy efficiency of your home, in addition to reducing your energy bills.

Potential to reduce heat loss in the home through built elements

Fuel poverty occurs when a household cannot afford to keep their home at a reasonable temperature. Fuel poverty is caused by a combination of low income, high energy prices and poor energy efficiency in the home.

In England, a household is in fuel poverty if required fuel costs are above the national median and if residents are left with a residual income below the poverty line after paying those costs.

Fuel poverty is a critical issue in London, and an estimated 13.25% of all households in Waltham Forest are living in fuel poverty.

Living in fuel poverty can severely impact the physical and mental health of occupants. Retrofit measures help to address fuel poverty, and there are a number of grants available to support landlords or residents who want to undertake retrofit measures, detailed further here.

3.4 Measuring retrofit

An EPC (Energy Performance Certificate) rating is a measure of a building’s energy efficiency, ranging from A (most efficient) to G (least efficient). You will need an EPC if you are planning to sell or rent out your home. In England only accredited domestic energy assessors can produce valid EPCs.

Landlords must provide tenants with a valid EPC showing energy use and cost, and they can be fined for non-compliance. Since April 2020, it has been a requirement for all rented properties to have a minimum E EPC rating. Making retrofit upgrades to a home to raise its EPC rating can help to add value when the property is sold.

Energy Performance Certificate (EPC) guide

3.5 Retrofit guidance in this document

The image in the right-hand bar shows some of the retrofit measures explored later in this document. There is no one-size fits all solution, but by planning and monitoring your existing energy consumption, where heat is lost and where condensation occurs, you can plan for suitable interventions for your home.