How Much Does It Cost to Tank a Cellar?

If you’re experiencing damp issues in your basement or cellar, tanking could be the ideal solution. A damp cellar can lead to structural damage, mould growth, and an overall reduction in property value. Tanking is a proven method to protect against moisture penetration, ensuring your basement remains dry and usable for years to come.

But how much does it cost to tank a cellar? The answer depends on various factors, including the size of the space, the extent of damp problems, and the type of tanking system used. Investing in cellar tanking protects your home and also increases its value and functionality. 

In this guide, we’ll explore how much it costs to tank a cellar, the different tanking methods available, and whether it’s worth the investment. 

What is Cellar Tanking?

Cellar tanking is a waterproofing method that involves applying a tanking slurry or membrane to walls and floors to prevent water ingress. It is essential for properties with moisture problems, especially in older buildings. Tanking can help transform an unusable, damp space into a functional storage or living area, making it a great long-term investment for homeowners.

If you are looking for more information and a free survey, feel free to reach out to us!

Factors That Can Affect The Cost of Cellar Tanking

Several factors determine the overall cost of tanking a cellar, including:

1. Size of the Cellar

The larger the cellar, the more materials and labour are required, increasing the overall cost. A small cellar may only require minor treatment, while larger spaces may demand extensive waterproofing measures and additional drainage systems.

2. Type of Tanking System

There are two main types:

• Tanking Slurry – A cementitious coating that creates a waterproof barrier. It’s usually more affordable and best suited for lower levels of moisture ingress.
• Cavity Drain Membrane System – A plastic membrane that directs water into a drainage system. It’s more expensive but highly effective, especially in properties with high water tables or significant external pressure.

3. Extent of Damp Issues

If your cellar has severe damp problems or structural issues, additional work such as crack repairs, drainage solutions, and reinforcing walls may increase costs. Older properties with porous walls may require multiple layers of tanking for complete protection.

4. Labour Costs

Professional installation ensures effectiveness. Costs vary depending on the contractor’s experience and location. Hiring a specialist who understands cellar waterproofing ensures compliance with building regulations and the longevity of the tanking system.

5. Additional Features

• Underfloor Drainage – Prevents water build-up under the floor, reducing hydrostatic pressure.
• Sump Pump Installation – Removes collected water efficiently, which is crucial for basements prone to flooding.
• Ventilation & Dehumidifiers – Helps maintain a dry environment, preventing condensation and mould growth.

Average Cost of Tanking a Cellar

The cost varies depending on the factors mentioned above. Here’s a rough estimate:

• Tanking Slurry: £40-£100 per square meter.
• Cavity Drain Membrane System: £80-£150 per square meter.
• Full Cellar Conversion: £10,000 – £30,000, depending on size, complexity, and additional features.

To get an accurate quote, it’s best to contact us for a property assessment and a free quote.

Is Cellar Tanking Worth It?

Tanking a cellar can:

• Prevent damp-related structural damage, which could lead to costly repairs if left untreated.
• Increase property value by making the basement a usable space.
• Provide additional storage or living space, increasing the home’s functionality.
• Improve indoor air quality by reducing mould risks and excess humidity.
• Help protect belongings stored in the basement from water damage.

Tanking a Cellar FAQs

How long does cellar tanking last?

A well-installed tanking system can last 20-30 years or longer with proper maintenance. Regular inspections and dehumidifier use can extend its effectiveness.

How long does it take to tank a cellar?

The duration of a cellar tanking project depends on several factors, including the size of the cellar, the tanking method used, and the extent of preparatory work required. On average, tanking a cellar can take anywhere from 2 to 7 days.

Can I tank my cellar myself?

DIY tanking is possible for small areas, but professional installation ensures long-term effectiveness. Incorrect application may lead to failure, requiring costly rework.

Does cellar tanking stop all damp problems?

Tanking prevents water ingress but should be combined with proper ventilation to avoid condensation-related dampness. A combination of methods often yields the best results.