Basement Conversions

Basement Conversions


Basement Conversions Chichester, Bognor Regis, Portsmouth, Basement waterproofing to transform your space


Waterproofing a basement for habitable use in your Chichester, Portsmouth or Bognor Regis property should be carried out using a qualified structural waterproofing designer with both professional indemnity insurance and public liability who will design a waterproofing system in accordance with #BS8102 and building regulations.

The basement design would be adapted by building control and fully understood and implemented by a suitably experienced waterproofing systems installer who in turn, could arrange to have a 10 year insurance guarantee issued on the installation.



Top Joints Construction Can help you Increase your living space & the equity of your property. Transform your space into bright comfortable habitable living area. When extending our homes, most of us would think of building outwards or into the loft, without giving a second thought to what lies beneath our feet. However, by digging down into the cellar or basement, you can create an additional floor running the entire length of your house, and that opens up a wealth of opportunities for a bigger and better home.

Basement Construction

Which types of properties are suitable?

A Basement Conversion is great for a terrace / semi-detached or detached, also ground floor flats. If building up is not an option and you have already extended into the loft, out the back / side of your property but still require more living space! Home Gym, Swimming Pool, Office Space, Kids Play Room, Cinema or just a place to chill out in with the Family, the options are endless.

Although when dealing with digging down to gain space is more costly, with most basement conversions when complete will add substantial value to your property.

Why Convert Your Basement?

In other parts of the world, in lots of homes, Basements are incorporated during the building process, for Utility Rooms, Play Rooms, Family Rooms etc…. The problem in the UK is space! The space below our feet, has great potential, maybe you have a dark and damp basement just forgotten about. This can be transformed to dramatically change your life style – home Gyms and Spas are very luxurious and very popular options!

Today’s Building Regulations means your once dark and dingy basement will be “modern, “warm, light and cosy!. With today’s technology we can install the latest heat recovery ventilation units – giving you slightly warmed continuous fresh air, also saving you on energy bills.

Construction Options

Excavating below your property using traditional underpinning, this is called a Retrofit. When excavating you are able to carry on living in your property. In most cases excavating you can choose to create amazing spaces to the full footprint bellow your property or just enough for your required additional living space. Your basement can also extend beyond the boundaries of you house by excavating into, bellow your garden.

The most cost effective option is to convert your existing basement / cellar. To gain head height the ground below can be lowered. Again in most cases using traditional underpinning. Create light wells for natural light / ventilation and fire escapes. Options are endless!

Project Management

This is key to running your project smoothly through the whole construction stages to completion.

Our working project manager is dedicated to completion of the contract and has duties to the client including:

  • Updating the client at every stage of planning and design changes
  • To confirm all stages of the contract before work commences
  • Full management of all tradesmen on sight daily
  • Rapid response to clients enquiries
  • To inform the client of any construction issue along the way and how to overcome them
  • To be first contact at all times during the agreed contract term set out until hand over
Things that may affect the cost of your conversion
  • Ground conditions for excavating
  • Where to store materials
  • Access to remove spoil from the basement
  • Under floor heating
  • Plumbing for showers and toilets
  • Electrics, lighting and Audio
  • Required head room
  • Parking for all tradesmen
  • Delivery access
  • Number of light wells and size
  • Ventilation systems



Kair Heat Recovery Extractor Fan

Introducing the K-HRV150/12RH


Another great product, solving mould, damp, and condensation problems which would be included in your basement conversion project. The Kair KHRV150/12RH Single Room Heat Recovery Ventilator is perfect for you if you are looking to solve a damp problem in one of your rooms. Such as your kitchen, bathroom, utility room, living room, lavatory, washroom, conservatories, office and bedroom. 


Continuous ventilation in your basement


This unit is perfectly suited to your needs as it automatically controls the humidity of your basement room for you, so you can relax knowing that it will take care of everything for you. The unit also offers you continuous trickle ventilation, so it will constantly clean and purify the air you breathe. Continuous ventilation is the key in keeping your home mould free.

Free extra set of filters: Register your product within 14 days of purchase and you will receive and extra set of filters for FREE!

Reducing heating bills: The unit is highly energy efficient so it will help you save money on your heating bill. Up to 86% heat recovered from extracted air, means even in cold winter weather the incoming clean air will remain at almost the same room temperature. 

Clean air for You and Your family: The unit is 100% completely safe for you to put in your bedroom or your child’s bedroom since it has a very low voltage, keeping you and your family safe. By providing adequate ventilation the unit maintains the recommended humidity levels, preventing harmful bacteria being breathed in.


  • Stops Mould, Damp and Condensation Problems
  • Save up to 86% of your heat, you will soon get lower heating bills
  • Perfect for the basement because it includes a night sensor
  • Quiet and powerful -Trickle 19m3/h / Boost 38m3/h Average daily airflow 547m3
  • This unit is perfectly suited to your needs as it automatically controls the humidity of your room for you, so you can relax knowing that it will take care of everything for you.



please phone  to discuss your project.

Office : 01243 602531