It depends on your circumstances: are you building, selling, buying or renting a house?

Building:

If you are a self-builder or a developer/builder you need to obtain a BER from a registered BER assessor for any new property today. The full cert is only available for buildings which are completed, a provisional cert can be obtained for those under construction or before construction, if full detailed drawings and specifications are available. This helps you obtain the best rating for your budget by making decisions at an early stage. A provisional cert is also useful if you are ‘selling from plans’. The provisional cert is valid for 2 years, and a full cert must be obtained when construction is complete. Depending upon which building regulations apply to you, a minimum rating of C1 is expected.

Selling:

If you are selling a new house, you will probably already have a BER cert. If planning permission for the dwelling was applied for on or after 1st Jan 2007, it would have required a BER cert, if you do not have one you need to get one. Since the 1st Jan 2009, all existing dwelling will need a BER cert if offered for sale, rent or lease. For older buildings you do not have to meet a specific rating, as building regulations changed over time, but you do have to have a rating.

Buying:

Since the 1st Jan 2009, as a prospective buyer you are entitled to know the BER for a building on sale, no matter how old it is. Before this date a ‘new’ dwelling may also have to display the rating, depending on when planning permission for it was sought.

Renting / Leasing:

Since the 1st Jan 2009, as a prospective tenant you are entitled to know the BER for a building available for rent or lease, no matter how old it is. If you are the owner of a building which you are renting out or it is being leased, you must obtain a BER cert, which your tenants are entitled to see. For older buildings you do not have to achieve a specific rating, as building regulations changed over time, but you do have to have a rating.