Retrofitting Your Basement: The Essential 3-Step Guide — Part 1: What Is Retrofit Basement?

Retrofitting basement | Retrofitted basement with a blue sofa, work desk and a TV.

Retrofitting Your Basement: The Essential 3-Step Guide — Part 1: What Is Retrofit Basement?

Many people nowadays want a basement added to their home, to provide extra space without expanding the building’s footprint. One of the ways of achieving this is to retrofit an existing cellar as a basement, and over the next few months, we’ll be offering a 3-step guide. This will cover suitability and costs vs. benefits, but we’ll be starting with the simple question — what is a retrofit basement?

What Is Retrofitting a Basement and Why Might You Need It?

Unlike countries such as the US, most residential properties in the UK don’t have any kind of basement, meaning you’d need to excavate one from scratch. Some, however, may have a simple cellar or other lower-level space, and retrofitting involves converting this into a habitable basement that meets modern building standards and regulations.

Many of us want more living space, especially given the changes in lifestyle since the Covid pandemic. With property prices soaring, though, and land at a premium, moving or building an extension may not be practical. A retrofit basement, on the other hand, is extremely cost-effective.

Besides improving your lifestyle, a retrofit basement can boost the value of your home substantially. It’s not hard to see why. A basement can be used for anything from a games room, a gym or even a swimming pool to a home office or a self-contained flat — perhaps for an adult child or use as a guest room.

What Are the Steps in Retrofitting Your Basement?

So what’s involved in the process of retrofitting your basement? There are five essential steps:

  • Structural assessment — Before you even make your plans, you need to find out whether the project is feasible. The structural assessment will reveal any issues with the structure you have that will need to be factored into your plans.
  • Waterproofing —  Your existing cellar may not be waterproof to the extent you’ll need for a practical basement, putting it at risk of mould or structural damage. Depending on your needs, the contractor may install tanking, membranes or drainage systems.
  • Insulation — Even more than the rest of your home, a basement is vulnerable to cold in the winter and heat in the summer. Insulation, such as rigid foam boards, spray foam or mineral wool, will help regulate the temperature and save on energy usage.
  • Ventilation —  Correct airflow and ventilation are essential not only for comfort but also to prevent condensation that will lead to dampness and mould. Your retrofit basement may require extractor fans or heat recovery units.
  • Interior finishing — Once the structural work is finished, of course, your basement will need to be transformed into a pleasant living or working space. This will require walls, flooring, lighting, plumbing and electrical systems to be installed.


What Do You Need to Remember When Retrofitting Your Basement?

Several factors need to be taken into account when planning your retrofit basement. You’ll have to ensure that your project conforms with building and planning regulations for safety, structural integrity and environmental sustainability, as well as any specific requirements in your area. Party wall agreements with your neighbours may also be affected.

A retrofit basement can do wonders for both your lifestyle and your property’s value, but with all this to get right, it’s essential to involve experts from the start. To make sure everything’s taken into account and you don’t have to go back to the drawing board halfway through, give U&M a call to find out how we can retrofit your basement.