Guide to Adding a Home Extension

Published on 7 August 2020

Adding and extension is a great solution when your home is on the small side but moving isn’t an option. The additional space can make all the difference when it comes to using your home, and it even adds value. The possibilities are many, from creating a porch to closing off an outdoor terrace or installing a pergola in the patio.

But before we decide to put the project into motion, it’s important that you take into account different technical, logistical and legal details creating a home extension so as to avoid any unpleasant surprises.


The Golden Rules for Building at Home


1. Find out if you Need Building Permission

Before starting the project, you should find out if you need building permission. If you build without permission, you could be fined or encounter problems later if you decide to sell the house one day. Generally speaking, small extensions don’t require permission, but you must meet certain requirements.

The extension can’t increase the original floor area of the home by more than 40 square metres, and also can’t reduce the open space at the back of the house to less than 25 square metres. If the size of the home has already been made larger in the past, the new and previous construction cannot exceed 40 square metres. In the case of townhouses, the extension at street level cannot exceed 12 square metres, including any other extensions that have been added previously.

You can learn about the specific characteristics of construction work that don’t require a permit and remember that if you need one, you’ll also need to submit a Notice to Proceed to the building control authority. Moreover, you'll have to submit it no more than 28 days and no less than 14 days before the start of the construction work.

2. Apply for Building Permission

You'll need a building permit in the following cases: when the extension involves structural changes, exceeds 40 metres, or when you want to add on in the front of the house and it exceeds two square metres. You'll also need a building permit if your house is a protected property. To obtain this permit, you'll need to submit a building plan, so you'll have to hire a duly qualified architect or engineer. 

Check with the Royal Institute of Architects of Ireland to find trained professionals who can carry out your project. The professional you hire will be in charge of analysing local development and zoning plans, evaluating the boundaries of your property and preparing the design to then manage the necessary permits. As a general rule, it can take about three months to obtain a building permit.

3. Get Several Quotes for the Construction Work

If you don’t need building permission or to hire an architect or engineer, then hiring an experienced construction company may suffice. However, keep in mind that an architect will not only help you to find design solutions that allow you to make the most of the space and your budget, but they'll also be responsible for planning the project and supervising the construction work to make sure it complies with all building regulations.

If you decide to hire a construction company directly, ask for different quotes to compare prices. Choose a company that inspires confidence and gives you guarantees as to the amount of time it’ll take and how the work will be done. What’s more, an experienced contractor can also give you useful tips to improve the project or save money.

4. Buy the Finishes Ahead of Time

Going out to buy the materials right when the work is about to start isn’t a good idea because you’ll have to be satisfied with whatever you find, and you’ll probably end up paying more. To save costs, it’s best to start buying the finishes a few months before the start of the construction work.

You’ll need time to find the doors, tiles or windows that you like the most at the most convenient price. If you start looking early, you can find good deals that will represent a considerable reduction in your final budget.

5. Check Your Insurance Coverage

When you add a home extension, you are the developer. This means that, although the construction company you've hired is directly responsible for any possible damages to third parties, as the owner, you are secondarily liable, meaning you may have to pay for damage or injury. 

Home insurance covers the damages that may affect the house as a result of ordinary use. But since a renovation or extension isn’t considered ordinary use, these types of claims aren’t covered. You need to contact us to discuss the work that's being completed so that we can properly advise you on the cover you have. If you don't contact us you may not have any cover. That’s why, before you get started, it’s important to check whether the construction company has insurance that covers the possible damages that may occur during the construction work.

When you finish the work, you must notify us that the work is completed and of the changes. When taking out a Home insurance, the policy includes the characteristics of the home, from the square metres to the quality of the finishes, based on which it calculates the risks, premiums and compensation you'll receive in the event you file a claim. If you don’t communicate the changes, you’ll likely find yourself underinsured.


Home Insurance with Liberty


With Liberty, you can get up to five weeks of free Home insurance* when you quote and buy online.


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*Online discount applies to new home policies only. Five weeks free equals a 10% discount. Maximum Buildings cover discount €40. Maximum Contents cover discount €15. Maximum Buildings & Contents cover discount €55. Subject to minimum premiums and applied before optional covers. Acceptance criteria, terms and conditions apply.