What is a Deep Retrofit?

House2GreenerHome: Your Complete Guide for Energy Efficient Home Improvements 

For a country which has a relatively mild climate, it seems surprising that many of our homes often feel cold. A survey carried out by iReach on behalf of the Irish League of Credit Unions earlier this year highlighted that 46% of people find their homes much colder than they would like to be.

As well as the discomfort of living in a draughty or cold house, there is also a cost implication. Colder homes need to use more energy to be heated or to remain warm. And of course, with most of Ireland’s homes being heated by oil, gas and solid fuels, there is a significant impact on the environment too. According to the SEAI, in 2017, the average Irish home emitted almost twice the energy related carbon dioxide emissions than the average dwelling in the EU.

What is a Deep Retrofit?

Retrofit (v) – to install (new or modified parts or equipment) in something previously manufactured or constructed

Quite simply, a deep retrofit of a home means carrying out multiple energy upgrades all at once to achieve a BER of A-rating. A deep retrofit is a combination of measures, which together, have a very significant impact on the warmth and comfort of the home.

Why is there a drive to retrofit homes?


It is estimated that 40% of Ireland’s energy-related carbon emissions coming from buildings alone. In keeping with the drive to reduce our carbon emissions, the Government has committed to retrofitting 500,000 homes to a B2 BER standard by 2030.

How do you know if your home might need a retrofit?

If your home is cold, damp and very costly to heat, it may be the case that you need a combination of measures to make the home more comfortable to live in. The age of your home is likely the biggest indicator of the requirement for a retrofit.

The chart below from the Central Statistics Office (CSO) highlights the Building Energy Rating of homes by year of construction. 97% of houses built since 2015 have an A energy rating compared to just 35% of houses built between 2010 and 2014.

What work is included in a typical deep retrofit?

As mentioned above, a deep retrofit will include a combination of measures. One of the key aims will be to reduce the level of heat which the house is losing. In other words, keep heat inside the four walls (and roof) for longer. This may include measures such as wall insulation, roof insulation, floor insulation or upgrading windows and doors.

An efficient renewable heating system will also be considered. A key aim will be to move away from the use of fossil fuels such as oil or gas. The typical heating system installed on a Deep Retrofit Project is a heat pump. You can find out more about heat pumps here.

A deep retrofit project may also look at mechanical ventilation with heat recovery unit  to maintain good indoor air quality.

Other energy efficient measures to be considered will be the use of solar water heating panels and solar pv panels.

How much does a deep retrofit cost?

The cost of a deep retrofit will depend on many factors. The type of house, its floor area, when it was built and the starting BER before work commences will all have an impact on the cost to upgrade the home. According to the SEAI, the average cost to upgrade a home from an average BER rating of F rating to an average A3 rating is €60,229.

What retrofit grants are available?

The Sustainable Energy Authority of Ireland (SEAI) runs the National Home Retrofit Scheme. Under the scheme, deep retrofit grants of up to 35% are available for homes which reach a Building Energy Rating of B2 are better. The scheme is available via approved service providers.

In order to help people to upgrade their homes, a number of credit unions in conjunction with Energia and House 2 Home, have launched the CU Greener Homes scheme, a one-stop solution for home energy efficiency upgrades. As well as offering all of the supports needed to carry out ‘green’ home improvements, applicants through the scheme can avail of discounts of up to 40% for qualifying work.

Green Home Improvement Loans

If you need any help to fund a warmer, greener home, talk to us here about a green home improvement loan today, or submit an online loan enquiry by clicking here.
Keep an eye out for #House2GreenerHome across FacebookTwitter, or Instagram for some great tips and advice on improving the energy efficiency of your home.  
* A €30,000 home improvement loan over 10 years at a 4.79% variable interest rate (4.9% APR) has 120 monthly repayments of €315.13.The total amount repayable is €37,815

Share this article