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How Much Does a Home Extension Cost?


Have a home extension project in mind? The price of extending your house can vary in relation to numerous different factors, including the type of extension you decide to build, who you choose to hire for the work, and the geographical location of the project. Here are a few factors to take into consideration to help you determine how much your home extension project will cost.

Home Extension Costs in Ireland

Where your home is located is one of the key factors that will influence the price of adding an extension. As with all types of architectural projects, the local cost of living and construction rates have a significant impact. Costs for home extensions are highest in Dublin compared to the rest of the country, but the effect of adding an extension to increase your property value will be much greater as well. Extending your house can add over 10% to your property value, and in some cases more depending on real estate prices in the area. The cost of an extension will generally be lower in other parts of Ireland, such as Cork, Kerry and the Border Counties. Quotes may differ if your house is located in a rural, less-populated area, where homeowners can pay up to 22% less for home extension projects. If there aren’t many architects and other construction professionals in the vicinity, however, you may find that they will charge slightly more due to the fact they have little competition, or to compensate for additional travel and transport expenses. 

Factors in Your Extension Projet

The cost of an extension will also depend on the specific constraints of your existing property and the type of extension you’re able to add, as well as the purpose of the proposed development. A simple conservatory or glass-walled sunroom can be one of the least expensive forms of extension, if you’re looking to add a small amount of space and bring natural light into your home. More complex extensions will naturally have higher costs, especially if structural alterations to the interior of your home are involved as well, such as to knock down walls to create an open-plan kitchen and dining area. Kitchen extensions are a popular form of home improvement project, and can be a great opportunity to remodel and modernise your home at the same time. If your extension project involves a new kitchen or bathroom, however, you’ll likely need to budget at least an additional €5,000 to €10,000 on top of the regular build costs due to the additional electrical and plumbing expenses, as well as fitting the kitchen or bathroom out with the necessary fixtures and appliances. A bespoke kitchen with a high-end finish can cost significantly more, but can be worth the extra money for the value it can add to your property. 

Whether you’re adding a rear extension or building out to the side or front of your property, there may be other factors to consider, especially if the proposed extension will impact your neighbours. Costs will also depend on whether you choose to build a ground floor or double story extension – the latter can even be a more cost-effective choice if you’re looking to significantly enlarge your home. If you don’t have much garden space surrounding your property, other options are possible to add space to your house. A loft conversion can be an inexpensive way to add an extra bedroom for example, or a basement conversion or extension is becoming an increasingly popular choice in areas where space is limited. 

Choosing Professionals for Your Extension Project

The professionals you choose to carry out the extension works will also be a factor in the overall price. In addition to the design and build, you may also want to consider project management as part of the professional fees included in your budget. If you choose to, you can manage the project yourself, which involves dealing with contractors, managing invoices, and making sure that the works progress smoothly and on time. While this naturally saves you the expense of having to hire a project manager, project management represents a significant time investment, and could also possibly lead to headaches if you are inexperienced in dealing with tradesmen and building projects. You may prefer to leave the project in the hands of a capable, experienced professional such as your architect. Many architects offer will offer a full-service package for your project to manage every aspect of your project, providing you with complete peace of mind. 

Hiring an architect is also the best way to ensure that you will have expertly designed plans, and the work will be carried out to a high standard without unexpected problems. This can save you money in the long run, especially as a quality, bespoke design can reduce the property’s long term maintenance costs and ensure your alterations add value for a solid investment. The price of an architect can depend on numerous factors, such as the scale of the project, their experience, and how much of your project they’ll handle for you. If your proposed development involves renovation work and structural changes such as knocking down load bearing walls, or if you have an old house with certain constraints, you may also need to factor in hiring a structural engineer.

Materials for a Home Extension

You will also have to factor in the price of materials. This, alongside labour, will make up one of the most significant expenditures of the project. The price of your home extension will depend on the quality of materials you go for as well as the quantity you will require. While it can be tempting to go for cheaper materials, bear in mind that the extension is going to be a part of your home permanently and will have an effect on its resale value, so it is important that the materials you choose are at least as high-quality as the rest of the property. 

Your choice of materials can also depend on aesthetic and environmental concerns. Timber is becoming an increasingly popular choice for extensions, as both an eco-friendly option and a stylish addition to your home’s façade. It can also be a cost-effective choice, depending on the type of wood you choose. You may want to choose an exterior material that matches your existing house’s cladding, or many homeowners who opt for more cost-effective materials choose a more modern and complementary style of extension that contrasts with the original property.