Building An Extension In Ireland

Building An Extension In Ireland

They say space is the final frontier. Well, it is for many Irish homeowners anyway. For many of us, the solution lies in extending what we have. So, we've asked experienced Dublin builders from to give us the scoop on planning and building a house extension.

I'm thinking of extending? Do I need planning permission?

Not necessarily. For example, homeowners can build an extension at the rear of their premises up to 40sq m in size, provided the house has not previously been extended and the extension observes certain rules relating to height and open areas. That's a good sized extension of 25ft x17ft.

If I do need planning, how long will it take?

From the time you submit the application, typically about 8-10 weeks.

How long will the build take?

Roughly, about 6-8 weeks for a single storey extension or 10-12 weeks for a two storey.

What are certificates of compliance?

If your extension involves any structural changes, you must get a certificate of compliance . This will be needed if you sell the house or to get a mortgage for the extension work. It can be provided by a surveyor, architect or other suitably qualified person with the correct indemnity insurance. This must be arranged before building work starts as it involves several site inspections.

What will the build cost?

One rule of thumb is €1,000 to €1,500+VAT per square meter. If the building work is straightforward i.e. doesn't involve moving drains or shores, it can be less. If it's complicated or involving high spec. materials, it could cost more.

What are our builders top 10 tips for a successful build?

  • Put time and effort into the plans. We find that homeowners who rush the design phase are more likely to need changes during the build than homeowners with detailed plans. That means expense and delays in the long run.
  • Hiring a professional architect will produce a carefully designed extension. In addition, their detailed drawings help homeowners visualise the actual outcome.
  • Get a proper builder. Don't choose the guy down the road just because he did some work for a friend. Get references and go and visit work that they've done.
  • Make sure everything is properly detailed and priced at the start including sockets and radiators.
  • Spend money on the fundamentals: good insulation, plumbing and electrics. The value of insulation can't be over-stated.
  • Think open plan. One decent sized room is far more useful than 2 small rooms.
  • A lot of people don't realize that an extension can substantially reduce light in the original house. The design of the extension must maximize light into the main house. Velux windows will let in far more light than standard vertical windows.
  • Vaulted ceilings are popular now on extensions as they're brighter and more spacious.
  • Retaining your architect for the building work means you will have a neutral 3rd party in the process.
  • Have a contingency budget of 10-15% put by. It's a pity to have a lovely build and then to have to really scrimp on the kitchen units or decoration.

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