When you hear the term basement, it may draw the picture of a dark, dank and uninviting space that is only good for storing unnecessary items and horror film locations. But this couldn’t be further from the truth.
In fact, in countries like the United States, basements are commonplace in the majority of homes and provide homeowners with more options for a wide variety of sophisticated living spaces.
If you’re thinking about extending your home and you’re not sure where to start, why not get in touch with one of our expert structural engineers in Devon today.
Why Should I Build A Basement?
Basements are a great choice of extensions because they can give you up to 50% more living space without using up any more of your land. this is especially good for inner-city properties which may not have enough land for an above-ground extension to be built.
Since they’re built into the bedrock beneath your home, basements are also naturally more soundproof than the rest of your home. Because of this, basements are perfect for teen hangouts, home cinemas or gyms and even at home music studios.
Despite commonly being seen as a secondary loft, basements are not always a cost-effective choice if you’re looking for more storage space. Instead, it may be more affordable to consider using an offsite storage unit or even building a garden shed.
Can I Build a Basement Under My House?
While there aren’t currently any legal reasons why you can’t build a basement under your home, there are some things that could hinder your chances of actually building one.
Firstly, not every property will be suitable for a basement and it’s actually thought to be better to build above ground extensions. This is because with above-ground extensions it’s easier to provide the extension with ventilation and natural lighting. Above ground extensions also tend to be more affordable.
Where is The Best Place To Build A Basement?
Some of the best places to build a basement are under houses that are in an area with higher land values, such as near city centres and the London suburbs. Basements are also a good choice for properties that don’t have much above-ground land to build an extension on.
Do You Need Planning Permission For A Basement?
As with most extensions, whether or not you require planning permission will depend on a few things, such as:
- The area you live in.
- Your house’s suitability.
- The project as a whole.
For example, if you’re planning on converting an existing basement, then much like a loft conversion, it’s unlikely you’ll need planning permission. If you’re interested in what other extensions you can make without planning permission, find out more on our blog.
However, if you’re building a basement beneath your home entirely from scratch then you will more than likely need planning permission.
Most councils are willing to give permission for a basement so long as certain conditions are met. These may include:
- Construction methods
- Site management
- Traffic management
- Safety on site
Make sure you contact your local council about planning permission before you start any building work.
Things To Consider Before Building A Basement
Before you begin planning or building your basement, there are some things you should consider.
It should go without saying that when you’re digging under your house, there may be some risks involved. This is mostly because you never know what you’re going to find under the surface.
That being said, there are ways you can reduce the risk before you begin building. Some of the ways you can minimise the risk include:
- Carrying out soil investigations.
- Digging inspection pits to confirm the level of the water table before confirming the type and scope of works.
- Confirming ground conditions and soil types.
Is Your Property Suitable For a Basement?
As we’ve said, not all properties are suitable for a basement extension. Make sure you do your research before you make any plans to build a basement.
If your property has any of the following, it may not be suitable for a basement:
- A high water table
- Unsuitable bedrock
- Existing structures and services
- Archaeological finds
How Much Does Building A Basement Cost?
A contractor will total the work for a basement according to four stages:
- Shell and core (the structure)
- Waterproofing (determined by the size of the basement space as well as the number of sump chambers and pumps needed)
- Fit out
- Maintenance (if a sump and pump are used)
Basements are typically more expensive than loft conversions per m2. If you’re building from scratch it could cost anywhere between £2,000-£4,000/m2. The exact cost of your basement will depend on certain factors including, but not limited to:
- The area you live
- Access to the site
- How easy it is to excavate and remove soil from the site
- Any site-specific factors such as diverting drains
You should also take into account the ongoing maintenance costs of having a basement, such as pumps and the cleaning of the perimeter drainage channels.
We hope this guide has given you all the information you need to start planning your new basement build.
If you’re interested in extending your house or you have another building project in mind, why not get in touch with us today?