Deep Retrofit Cost Calculator Ireland

How Much Does a Deep Retrofit Cost in Ireland?

Use our deep retrofit cost calculator to estimate the cost for your home. Note however – these figures are very approximate. Every house is different.

The cost of a deep retrofit varies widely, mainly depending on:

  • The energy efficiency of the house before the retrofit
  • The desired energy efficiency after the retrofit
  • The size of the house

However, it would be fair to say that most deep retrofits cost somewhere between €30,000 and €70,000, excluding grants. The SEAI deep retrofit grant brings the final cost to the homeowner down to somewhere between €15,000 and €45,000.

What is Involved in a Deep Retrofit?

A deep retrofit is a collection of home energy upgrades that bring a home up to a high standard of warmth and energy efficiency. Specifically, this means achieving a Building Energy Rating (BER) of B2 or better.

The exact works carried out depend on what your home needs most. However, almost all deep retrofits include insulation upgrades. Installing a heat pump is also very common. On the other hand, solar panels make an optional cherry on top. Your deep retrofit contractor will help you decide on the best energy upgrades for your home.

If you’re wondering what upgrades to include in the deep retrofit cost calculator, here are some guidelines. The key is to first ensure the building has a warm “fabric”:

  • Attic insulation is essential (if you don’t already have it)
  • You’ll also need to make sure your home has at least one kind of wall insulation
  • Any draughty or single-glazed windows will need upgrades, too
  • Also consider improving air-tightness and heat recovery ventilation

Only after the building fabric is up to standard should you add a heat pump and solar panels.

Is There A Grant For Deep Retrofits in Ireland?

The SEAI (Sustainable Energy Authority of Ireland) provide grants for deep retrofits. The rate is 50%, up to a maximum payout of €25,000. Example: If the cost of works is €40,000 then you’ll get a grant of €20,000, so the net cost to you will be €20,000.

Who is Eligible for a Deep Retrofit Grant?

Most Irish homeowners are eligible for a deep retrofit grant. Better yet, you can claim a deep retrofit grant for multiple properties. This includes holiday homes and rental properties. Here are the requirements:

  • Your house was built before 2011 (defined by date of electricity connection)
  • Your house has a current BER of B3 or lower

To be awarded the grant, your retrofit contractor will ensure the home:

  • Achieves a BER of B2 or better after the retrofit is complete
  • Reduces energy usage by at least 100 kWh per square metre of floor are per year
  • Does this using energy upgrades that you have not previously got a grant for

How Long Does a Deep Retrofit Take

A deep retrofit typically takes several weeks, but there are exceptions, with some jobs completed in a matter of days. It all depends on the specific upgrades – see the table below:

UpgradeDuration of WorkDisturbance to Occupants
Solar panels
Attic insulation
Wall cavity insulation
Heat pump*
1-2 daysLow
Underfloor insulation
Internal wall insulation
1-2 weeksHigh – may need to move out
External wall insulation1-2 weeksMinimal – no need to move out
*provided underfloor heating is not needed

Ready for A Warmer Home?

A Home Energy Assessment or Technical Assessment is the first step towards your home energy upgrades. Here’s why:

  • Independent advice from an SEAI-registered and qualified professional
  • Qualifies you to apply for SEAI grants, including the €6,500 heat pump installation grant
  • Grants up to €350 towards the assessment cost

The founder of Ecoplus Survyeors Limited, Dominic has worked with sustainable energy since 2019. He writes about energy-related topics, including heat pumps and solar PV. In his spare time, Dominic enjoys playing traditional Irish music and riding mountain bikes.