Basement Conversion Guide For Beginners

Basement conversions are something that many homeowners have thought about, especially if you are a growing family in need of more living space. Basements are a solution for creating space in crowded urban areas where outdoor, ground-level space is limited. This is similar to the advantages of a loft conversion; however, lofts are more ideal as a bedroom or bathroom, whilst a basement is closer to the main living area and would be ideal for creating more living and leisure space for your family members.

So if you don’t have the permission or means to expand your home above ground, why not choose a basement conversion which will tackle the problem from the ground up, adding space as well as value to your home.

Options for Basement Construction

There are a few options for creating a basement and the one you choose will be down to your property and the area around you.

Ultimately, there are two types of basement construction;

The first option would be to convert an existing cellar or basement into a more habitable and functioning space.

The second option is to create a new basement by either extending the underneath of the home or by building a semi basement that extends out into the garden or the side of your house.

The first option is the most cost effective because there is already an existing foundation that you can add to. It is easier to add to something than to start from scratch.

The second option is a more comprehensive and costly construction that includes excavating the ground below your house or property and building a basement that has a strong foundation and the structural work will be more extensive.

Uses for Your New Basement

A basement extends the space in your family’s home as well as providing more practicality and not to mention, it will increase your property’s value if you are looking to sell your home at some point. A basement is the perfect location for another living room, playroom, games area, home cinema or home entertainment room. 

It can also be a great way to free up space in the rest of your home by being the ideal space to be your laundry room or utility room where you can keep your boiler and storage.

On the other hand, you can also build a basement with an external entrance that leads into the garden, also known as a semi-basement on a sloped site and provide a contained unit that would be great for certain purposes such as a  home office, annexe or a conservatory.

Cost of Basement Conversion

You will need to decide whether or not a basement conversion or construction is financially viable. This will all depend on the budget you already have and the work you will need done on your home in comparison to the local property values in your area.

It would make more sense to add a basement or a lower ground storey if the local property values for land are higher (such as in London and urban areas), because basements don’t need to take up additional above ground land. 

If you are trying to save money on your basement conversion or if you think that you are better off getting your basement converted at a very low price, then put into perspective that a good quality, professional standard basement that is well lit and waterproofed is more functional and worth more of an investment than a 4x4 basement cellar with no lighting and minimum headroom. 

The factors that contribute to the cost of your basement conversion will include:

• If you have an existing cellar or basement
• If you need more headroom and your basement ceiling expanded
• Waterproofing and tanking services
• Building regulations and planning permission payments
• Refurbishment/painting and decoration
• Gas, plumbing and electricity
• Poor site access
• If drains need to be diverted beneath your house
• If your house has solid concrete subfloors rather than timber
• The local water table is high an needs constant pumping

Building Regulations and Planning Permissions

Building Regulations are legally required when building a habitable basement area in your home or property. The Building Regulations Act is a constitutional minimum requirement in construction standards and it ensures that buildings are safe, energy efficient and hygienic enough for people to properly live in and use.

For basement conversions, it is best to apply for a Full Plans Application which is better than following the Building Notice procedure because it allows all of the design process to be resolved in advance before work is carried out.

Party Walls

The Party Wall Act is another thing to consider when building a new basement. If the beams supporting your home bear onto a Party Wall and need to be altered, underpinned or extended, then the Party Wall’s owners (neighbours) will need to be informed by the person getting the basement conversion.

Basement Tanking and Waterproofing

Waterproofing your basement is essential because it maximises the lifespan of your basement. Because the basement is underground, it will be susceptible to damp walls and rotting wood if the walls, floors and ceilings are not properly waterproofed and tanked. To avoid ruining the basement’s structure and interior, you should take precautions to avoid this before it compromises the strength of your basement’s structure. It is also a good idea to get your basement waterproofed during the conversion process to avoid additional expenses and inconvenience.

Waterproofing below ground level is also called tanking. It refers to the method of applying a waterproof layer or material to the structure of your room. It is a system that is applied in several layers that is linked to a waterproof screed on the floor.