The Role of Basement Tanking in Basement Conversion Projects

The Role of Basement Tanking in Basement Conversion Projects

8th September, 2023

Basement conversion projects have grown in popularity in recent years, and for good reason. As property owners seek to maximise their living spaces, basement conversions offer the perfect opportunity to do this without extending a property outwards. Converting a basement into a functional living area offers a huge number of benefits, from additional bedrooms and entertainment spaces to increasing the overall property value. However, these conversions come with their unique challenges, with damp being one of the most common concerns. This is why basement tanking can be highly effective, playing a crucial role in ensuring the success and longevity of a conversion. In this guide, we’ll be discussing everything you need to know about basement tanking – read on to find out more.

What is Basement Tanking?

Basement tanking, sometimes referred to as basement waterproofing, is the process of applying various materials, like a coating or membrane, to the interior or exterior of the basement, to prevent water from penetrating the space. It aims to create a barrier between the inside of the basement and the surrounding soil or groundwater, which not only prevents water ingress but also protects the structural integrity of the building and the overall quality of the indoor environment.

Basement tanking solutions can be broadly categorised into two main types: internal tanking and external tanking.

What is Internal Basement Tanking?

Internal tanking involves applying waterproofing materials to the interior surfaces of the basement walls and floors. This approach is commonly used when retrofitting existing basements, especially in older properties, due to the flexibilities available in the materials used – some of the most common materials used for the internal tanking process include:

Cementitious Coatings: These coatings are applied as a mixture of cement and additives that create a waterproof layer when applied to the surfaces. They are highly versatile and can be used on a range of substrates, including concrete and masonry, so they’re suitable for a whole host of different property types.
Cavity Drain Membranes: Cavity drain membranes consist of a studded plastic membrane that is fixed to the walls and floors. The studs create a gap between the membrane and the surface, allowing water to be channelled and managed effectively through drainage systems.
Waterproof Renders and Plasters: For a more specialised approach, renders and plasters are designed to create a waterproof layer that can be applied directly to the walls and floors.

What is the Difference Between Internal and External Tanking?

Basement tanking comes with several benefits that can not only protect your property but also improve your living space:

Preventing Water Damage: Water infiltration is a major concern in basement areas, primarily due to their location. Without effective basement tanking, water can seep through walls and floors, leading to issues like dampness and mould growth. These problems not only compromise the appearance of the space but also pose risks to the health of occupants and the structural integrity of the building.
Protecting Property Investment: A basement conversion project represents a significant investment in terms of time, money, and effort. Implementing proper basement tanking is essential to safeguard this investment, and by preventing water-related issues, you can ensure that your newly converted basement space remains functional and aesthetically appealing for years to come.
Enhancing Liveable Space: Basement conversions are often aimed at increasing the available living space within a property. Whether the basement is transformed into a cosy living room, a home office, or even an additional bedroom, the success of the conversion depends on creating a dry, comfortable environment. Basement tanking plays a pivotal role in achieving this goal, making the space habitable and enjoyable for occupants.
Compliance with Regulations: In the UK, there are many regulations that your basement conversion must meet, and these include adequate waterproofing measures that need to be carried out before the space can be classed as liveable. Using proper basement tanking methods will ensure that your project complies with these regulations, and help you avoid potential legal issues.

What Factors Should I Consider During a Basement Tanking Project?

Given the benefits of a basement conversion, it’s easy to overlook some of the crucial elements of a basement tanking project – here are four of the most important factors to consider:

1) Type of Tanking System: The choice between internal and external tanking depends on several factors, including the existing structure, site conditions, and budget. Internal tanking is often favoured for existing buildings due to its ease of application and minimal disruption to the property, while external tanking provides a comprehensive solution from the outside but requires excavation – which can be more complex and costly.
2) Type of Drainage System: An effective drainage system is an integral part of any basement tanking strategy. In internal tanking systems, cavity drain membranes direct water toward drainage channels, where it can be safely removed from the basement. External tanking systems also rely on proper drainage to prevent water accumulation against the external walls.
3) Professional Expertise: Basement tanking is a specialised process that requires a lot of knowledge and expertise. It’s always vital that you consult with experienced professionals like us to assess the specific needs of the project and recommend the most suitable tanking solution.
4) Maintenance Considerations: Regular maintenance is essential to ensure the longevity of basement tanking systems – While these systems are designed to provide long-term protection, periodic inspections and maintenance can address any potential issues before they escalate. Clearing drainage channels, checking for cracks, and addressing any signs of deterioration are important steps in preserving the tanking system.

Basement conversion projects offer a creative solution to space constraints and can significantly enhance the value and functionality of a property. However, the success of such projects hinges on addressing potential challenges like water ingress or rising damp. Basement tanking therefore plays a pivotal role in preventing water-related issues, protecting your investments, and ensuring the durability of the newly converted space. By seeking professional guidance, carefully considering the type of tanking system and committing to regular maintenance, you can confidently embark on a basement conversion project that stands the test of time.

Damp Survey Costs

Transparent pricing with no hidden fees for our independent, unbiased surveys.

Level 1

Level 1

£199 + VAT

What’s included:

  • Inspection of walls
  • Inspection of floors
  • Inspection of ceilings
  • Leak inspection of drains and plumbing
  • Damp information and prevention guide
Level 2

Level 2

£299 + VAT

What’s included:

  • Everything in Level 1
  • Dry rot inspection
  • Wet rot inspection
  • Woodworm inspection
  • Damp information and prevention guide

 Survey Add Ons

Add On 1

£299 + VAT
Lab Analysis Of Plaster

Laboratory analysis Of plaster identifies hygroscopic salts such as chlorides and nitrates. which indicate whether damp is caused by rising groundwater or by plumbing leaks, This testing removes guesswork, allowing the exact source of moisture to be identified so the correct treatment is applied rather than carrying out unnecessary damp-proofing work.

Add to Survey

Add On 2

£299 + VAT
Mould Lab Swab Testing, qPCR on DNA

qPCR DNA mould testing detects microscopic mould spores that are invisible during a normal inspection and van remain hidden behind walls, floors. or inside building rkaterials. It identifies the exact mould species present and the contamination level, allowing hidden mould problems to be confirrned and properly treated before they affect the property or occupants’ health.

Add to Survey

Qualifications: All our surveyors are PCA and CSRT qualified for remedial treatments and also CSSW qualified for structural waterproofing.
Next day report: You will receive the report within 24 hours of the inspection taking place.

These are the tools we use

Damp Meter

Damp Meter

A damp meter is a diagnostic tool used to detect and measure moisture levels within building materials such as plaster, brick, timber, and concrete.

Borescope camera

Borescope camera

borescope camera is a small inspection camera attached to a flexible semi-rigid cable that allows you to see inside areas that are otherwise inaccessible.

Drone Inspection

Drone Inspection

A drone is a remotely operated aerial device equipped with a camera that allows visual inspection from above without the need for scaffolding or ladder.

Air Humidity Sensor

Air Humidity Sensor

Air humidity sensor measures the amount of moisture present in the air, expressed as relative humidity (RH) in percentage. It helps determine whether indoor conditions are contributing to condensation, mould growth, or damp-related issues.

Thermal Imaging Camera

Thermal Imaging Camera

A thermal imaging camera detects temperature differences on surfaces by using infrared technology to produce a heat map image. In damp investigations, it helps identify cold spots, moisture intrusion, insulation defects, thermal bridging and leaks.

Air Flow Ventilation Detector

Air Flow Ventilation Detector

An air flow ventilation detector measures the movement and volume of air passing through vents, extractor fans, and air bricks. It confirms whether ventilation systems are working properly and achieving adequate air changes within a room. Poor airflow leads to trapped moisture, high humidity, condensation on cold surfaces, and ultimately mould growth.

Mould Lab Swab Testing

Mould Lab Swab Testing

A mould swab test is carried out to confirm the presence of hidden mould growth and identify the specific species involved. Surface mould is not always visible, especially behind furniture, inside cavities, or within ventilation systems. Laboratory analysis of a swab sample determines whether active mould spores are present and what type they are, which helps assess potential health risks and decide the correct remediation approach rather than relying on visual assumption alone.

Lab Analysis of Plaster

Lab Analysis of Plaster

Laboratory analysis of plaster is used to identify the type of salts present within the material, typically chlorides and nitrates. The presence and concentration of these salts help determine whether the moisture source is consistent with rising damp, ground contamination, or another forms [sic] of water ingress. such as mains water leak, This removes guesswork and prevents misdiagnosis, ensuring the correct remedial treatment is specified rather than applying unnecessary or ineffective solutions.