Two Storey Extensions Versus Single Storey Ones – The Key Things All Homeowners Must Consider

If you are planning an extension on your home, then one of the very first decisions you will need to make is the scope of the project. This really comes down to the number of square metres that will constitute the footprint of the new part of the building as well as one more crucial factor: whether you will build one or two storeys. 

Of course, any home extensions can be done in either fashion so long as you already have two storeys to work with. Let’s put aside the notion that you might want to build a two storey extension onto a bungalow and examine the most important aspects of which sort of project will be best for your circumstances. There is a little bit more to it than you might imagine at first! 

Planning Consent Considerations

Firstly, you should be aware that only certain types of house extension are permitted in the country without planning consent being granted by the local authority. Extensions that will exceed four metres in height will require full planning consent. Those which are underneath this height – and most single storey extensions will be – don’t necessarily require planning permission. That said, even if your project won’t go any higher than the four-metre limit, including any pitched roof that might be a part of the design, you may need to ask for permission anyway. 

For a start, if your home renovation project extends over 40 square metres, then regardless whether it will go above four metres, planning permission will be needed. Equally, if your house extension will be at the front of your home, rather than the back or the side, then planning consent is required. Finally, extensions which take up a high proportion of the remaining land in your garden will need to be granted planning permission to proceed. 

Therefore, if you are put off building a two storey extension on your home because you don’t want to seek planning permission, then know that you may be required to go through this process anyway, depending on the exact nature of your project. True, single storey projects under certain limits are easier to get going because you don’t need planning permission. However, if you are going to apply anyway, then what’s the difference in obtaining permission for a two storey addition to your home? 

Cost Considerations

Any home extension you choose will mean spending your hard-earned euros. At BIY, we make the whole process as cost-effective as possible, but you should always weigh up the additional outlay of two storey extensions versus the lower financial risk involved with a single storey one. Going up an additional floor means digging deeper trenches and pouring more concrete to make foundations. Then, there’s more brickwork and other building materials to consider. You’ll need to factor in additional wiring, plumbing, fixtures and fittings, too.

Of course, one of the main points of a home extension is to add value as well as provide more space. Additional upstairs room will certainly make your home more attractive to potential buyers should you come to sell it. However, opting for two storeys means more financial commitment in the here and now. 

Spatial Considerations

It doesn’t take a genius to realise that a two storey extension will offer you double the internal space compared with a single storey one for the same footprint. However, ask yourself what you need upper storey space for? An extra bedroom may be great but you don’t really benefit from additional living quarters by adding extra space upstairs. Besides, converting your loft or garage may be a more cost-effective way to add a spare bedroom or two than building a full extension over two floors. That said, upper storey space could make for a luxury bathroom or even a roomy home office, so there are options other than bedrooms with two-floor extensions. 

Aesthetic Considerations

Single storey extensions are relatively simple to design. Even a straightforward cube built onto the back of your home will look good with the right finishing touches. The same case cannot be made so easily if you are dealing with an extension over two floors, however. Firstly, the additional height needs to be factored in much more carefully from an aesthetic point of view because, quite simply, you can see two storey extensions from a lot further away. They generate more shade, look more impactful and could mean that you are able to overlook neighbours’ gardens with greater ease, all important considerations for their overall design.

Indeed, any materials you might want to use may stand out much more if they are used over two storeys, not just one. This might mean you alter the look of your design, so it is more ‘in keeping’ with the architecture in your part of the country. As a result, double storey extensions tend to be a little less architecturally interesting than their single storey counterparts. 

Turn to the Experts

At BIY, we have the expertise in building design to help you get the right look for your project whether you decide to go for a house extension over one or two storeys. We possess the know-how to be able to put together a plan that means you are more likely to get the planning permission you need for most two storey extensions in Ireland and will be able to guide you with your project so that construction costs are kept to a minimum. We are the perfect place to turn for home renovation and extension projects of all kinds. Contact BIY