Avoiding Damp Problems in a Basement Conversion

 Converting a basement can be the perfect way to expand your living space, particularly in city dwellings. But keeping it dry is not always easy.

 Extending down is on the up, and nowhere more so than in the capital. Since 2013, the number of planning applications for basements in the city has risen by almost 200 percent, compared with a rise of just 43 percent for loft conversions and a slight drop in popularity for conservatories and porches.

Improving versus moving

The reason is clear. A large proportion of residential properties in London date back to Victorian times and were originally built as two up, two down terraces. Many have already been extended at the back and have had the lofts converted to create more space. So, for those who want to create more living space and avoid the cost of moving, the only direction left is downwards.

It is also very common for many London residences to already have a basement that is underutilised, making it an obvious choice for conversion into useful living space. There has been a marked change in attitudes over the period since the house was originally constructed. Basements were originally used for cooking or as servants’ quarters and would not have been contemplated for day to day life. As lifestyles changed, the basement became superfluous, a damp, musty, forgotten place, used for storing junk and little else.

Keeping the Basement Dry

There are some obvious parallels with basements and loft conversions to create extra space. The clear difference is that being below ground, the basement is naturally more at risk of damp and whether you are breathing new life into an existing basement or digging out a new one from scratch, keeping it free from damp and even flooding is going to be one of the biggest challenges. So the basement tanking systems used to keep a basement dry are a vital consideration.

Basement Waterproofing Systems and Contractors

A sound waterproofing or tanking system designed around the natural drainage characteristics of your property is essential. Systems will involve the use of cavity drainage membranes, sump and pumps and a cementitious (cement based) waterproof render all which work in combination to act as the barrier to send water away from the property. Getting the design of the waterproofing system is therefore a top priority.

The next essential step is the quality of workmanship of the system installed to ensure a basement remains dry. Over recent years, the industry has seen far more regulation to ensure work carried out is performed correctly and to the highest of standards and the teams used, from architects through to the basement waterproofing contractors, need to be vetted for their skill and experience in this field of construction.

The regulations

Regulation does exist to control and provide guidelines in the form of British Standard 8102:2009 which is the ‘Code of Practice for Protection of Below Ground Structures Against Water from the Ground.’

Quite simply, there needs to be a fundamental consideration with a new basement and conversions. Even if the basement has been there for 100 years, it is highly likely no one ever thought about properly damp proofing it before now. The goal now is to take the right steps to make sure the new basement stays dry and trouble free for the next 100 years and onwards.