What do you do when you need more space and the thought of moving makes your head spin? Dig a basement! It’s a London thing.
Basements are increasingly popular as a means of creating space in homes across London. There is little space for extensions in our tiny London gardens, the loft was done years ago, and the kids have grown so fast! The cost of moving can also be a deterrent when you consider the likely increase in mortgage, estate agent fees, stamp duty, movers, etc. as well as the logistical disruption which may include a change in schools and other location factors.
As an alternative, digging a basement can add valuable space for living and increase the value of your home without changing your current routine. Of course the cost of excavation must be considered and a proper evaluation completed before a decision can be made. Cost of fittings vary though generally, digging a new basement space and underpinning can cost between £2,000 – £3,000 per square meter, whilst digging a new basement space underneath a garden can cost approximately £1,500 – £2,000 per square meter. So what are the steps to consider?
- Financial review and a cost/benefit analysis of moving vs excavating
- Most Councils require a Geological Survey and a Basement Impact Assessment to understand the type of soil and water levels for proper structural support and drainage.
- Architectural drawings for design and planning permission (some basements are allowed under permitted development and therefore do not require planning permission)
- Building regulation drawings
- Structural Engineering drawings
- Party wall agreements if required (for neighbours that share a wall or live within 3 meters of the dig)
- Hire a builder (it is essential to hire a builder with basement experience. Underpinning is difficult and can not be rushed. Mistakes can be costly and damage your home along with your neighbours!)
- Glass floor lights placed in good sunny locations can fill the lower rooms with light.
- An open floating staircase will help keep the basement light and airy.
- Ceiling height should be above the minimum 2.1 meters to ensure the space does not feel like a basement and double height areas should be considered if space is available to create the wow factor.
- Also careful consideration on ventilation, drainage and fire safety are key to long term enjoyment of a new basement . Waterproofing is installed behind the plasterboard, though a primary and standby pump are located under the floor to resolve any water issues. Pumps must be accessed for maintenance, and should be placed in laundry rooms or bathrooms if possible to maintain the luxury flooring in the main living areas.
- Boilers and other equipment can be located in hidden wall closets to preserve space.
- Lighting will add atmosphere if layered effectively.
- Don’t paint it white! This can be too sterile for a basement. Add colour or a light grey for neutral tastes.