New Build BER:
The Complete Guide for 2025

What is a New Build BER?

A Building Energy Rating (BER) is an energy performance certificate for a building, similar to the energy label on a household appliance. For new dwellings in Ireland, the BER process has two stages: the provisional BER (design stage) and the final BER (as-built stage). Both are mandatory under Irish building regulations.

The BER scale runs from A1 (most efficient) to G (least efficient). Under current Part L 2019 regulations, all new dwellings must achieve a minimum rating of A2 — and most well-designed new builds achieve A1 or A2 comfortably.

Provisional BER vs Final BER

The provisional BER is produced at design stage from your architectural drawings and building specifications. It demonstrates that your proposed design will meet the minimum energy performance requirements before you start building. You need this before submitting your commencement notice.

The final BER is the as-built assessment, produced after the dwelling is substantially complete. A BER assessor visits the site to verify that the building was constructed as designed, and the final rating is published to the SEAI national register. This is the certificate that must be provided to any buyer or tenant.

When Do You Need Each Certificate?

Provisional BER

• Before submitting a commencement notice to Building Control
• During planning/pre-construction to verify design compliance
• When applying for development finance (some lenders require it)

Final BER

• Before a dwelling is offered for sale or lease
• Before occupation of a new dwelling
• When registering with SEAI (mandatory for all new dwellings)

What Affects a New Build BER Rating?

The BER calculation considers the building's fabric (walls, floors, roof, windows), heating system, hot water production, ventilation strategy, lighting, and renewable energy systems. The key factors that most influence the rating are:

• Insulation levels — wall, floor, and roof U-values
• Heating system efficiency — heat pumps score significantly better than gas or oil boilers
• Airtightness — tested air permeability directly affects the calculation
• Renewable energy — solar PV, solar thermal, and heat pump contributions
• Thermal bridging — junction details and their associated heat loss

How Much Does a New Build BER Cost?

For individual dwellings, a provisional BER typically costs from €250+VAT and a final BER from €200+VAT. These costs include the SEAI registration fee of €30 per certificate. For developers with multiple units, volume pricing is available — the per-unit cost decreases significantly with scale, particularly for repeated house types where the same energy model can be applied across identical units.