What Is Tanking In Construction?
What Is Tanking In Construction?
Tanking in construction, also known as below grade waterproofing, involves applying a waterproofing barrier to the walls, base slab, and sometimes the roof of a below grade structure. The goal of tanking is to protect the entire envelope of the below grade structure from water ingress.
There are three types of waterproof tanking: waterproof concrete, drainage or cavity wall construction, and waterproof membranes. The choice of tanking method depends on factors such as the use of the space, budget, and desired performance. Waterproof concrete is the least expensive option but may not be suitable for high-risk projects or finished spaces.
Drainage systems allow water to enter the outer wall and then pump it out, while waterproof membranes physically stop water from entering the structure. Tanking membranes that have an adhesive bond to the concrete offer enhanced protection and durability.
Key Takeaways:
- Tanking in construction is the process of applying a waterproofing barrier to below grade structures.
- There are three types of tanking methods: waterproof concrete, drainage systems, and waterproof membranes.
- The choice of tanking method depends on factors such as project requirements, budget, and desired performance.
- Waterproof membranes with adhesive bonds provide enhanced protection and durability.
- Tanking is crucial for safeguarding below grade structures from water ingress.
Types of Tanking Methods in Construction
When it comes to tanking in construction, there are two common methods that are widely used: tanking slurry and waterproof tanking membranes. These methods provide effective waterproofing solutions for different types of structures and surfaces.
Tanking Slurry
Tanking slurry, also known as cementitious tanking, is a popular choice for waterproofing masonry surfaces. It is a thick liquid coating made of cement fortified with polymers and aggregates. Tanking slurry is known for its reliability and ease of installation. It can be applied to both damp walls above ground and below ground structures, providing a durable and effective waterproof barrier.
Waterproof Tanking Membranes
Waterproof tanking membranes are sheets of specially designed plastic material that act as a waterproof barrier. These membranes are made from high-quality HDPE and are designed to withstand temperature fluctuations and exposure to water. They are available in various thicknesses and can be installed externally or internally.
External tanking involves applying the membrane to the outer surface of the structure, providing protection to the main structure from water ingress. Internal tanking, on the other hand, utilizes the structural walls and floor slab to retain the excavation. The choice between tanking slurry and tanking membranes depends on the specific project requirements and preferences.
Overall, both tanking slurry and waterproof tanking membranes offer effective solutions for waterproofing below grade structures. The choice of method depends on factors such as the type of structure, desired performance, and budget. By selecting the most suitable tanking method, construction professionals can ensure long-lasting waterproofing and protection against water ingress.
Table: Comparison of Tanking Methods
| Tanking Method | Advantages | Disadvantages |
|---|---|---|
| Tanking Slurry | Reliable and easy to install | May not be suitable for finished spaces |
| Waterproof Tanking Membranes | Excellent durability and protection | Higher cost compared to tanking slurry |
Important Considerations for Tanking in Construction
When incorporating tanking in construction projects, there are several crucial factors that should be taken into consideration to ensure the effectiveness and longevity of the waterproofing system.
Tanking Thickness and Application
The thickness of tanking materials, such as mastic asphalt or tanking slurry, should be carefully determined based on the surface and slope of the area being tanked. It is essential to choose the appropriate thickness for both horizontal and vertical surfaces to provide optimal protection against water ingress.
Proper Backfilling Techniques
Backfilling is a critical step in tanking projects. It is important to backfill in layers and ensure proper compaction to prevent any deformation of pipes and to maintain the stability of the structure. By following recommended backfilling practices, potential issues can be minimized, ensuring the long-term integrity of the waterproofing system.
Damp-Proof Membrane (DPM) Considerations and Placement
For installations involving damp-proof membranes (DPM), careful attention should be paid to the lapping and sealing of joints to create a continuous and secure waterproof barrier. It is also crucial to place the DPM before the construction of walls above the DPC level to establish a proper connection. Additionally, avoiding sharp points that may damage the DPM and providing adequate support and protection to the tanking membranes is of utmost importance.
By addressing these tanking considerations, such as tanking thickness, backfilling techniques, DPM considerations, and proper DPM placement, construction professionals can ensure the durability and effectiveness of tanking systems, providing long-lasting protection against water ingress in below-grade structures.
FAQ
What is tanking in construction?
Tanking in construction, also known as below grade waterproofing, involves applying a waterproofing barrier to the walls, base slab, and sometimes the roof of a below grade structure to protect it from water ingress.
What are the types of tanking methods in construction?
The two common tanking methods in construction are tanking slurry, a thick liquid coating applied to create a waterproof barrier, and waterproof tanking membranes, sheets of specially designed plastic material that act as a waterproof barrier.
What are the important considerations for tanking in construction?
When implementing tanking in construction, important considerations include the appropriate thickness of tanking materials, proper backfilling and compaction, proper lapping and sealing of joints for damp-proof membranes, and ensuring the placement of DPM before building walls above DPC level.