How the Right Drainboard Can Protect Your Project

Shield Your Structure: How the Right Drainboard Can Safeguard Your Project and Your Reputation


No matter what type of building or project you’re taking on, water protection is a critical component to consider. Pooled water, moisture, temperature changes, and season changes can all affect your structure’s strength, durability, protection, and overall life expectancy. 

To ensure proper water drainage, you need a high-performing drainboard. Unfortunately, most of today’s drainboard solutions are not able to provide the long-term, universal protection necessary for today’s builds. Over time, standard drainboards become less efficient, leading to more moisture-related headaches.

As architects and specifiers, it’s important to choose a drainage system that has the drainage capacity and durability to last and keep your structure standing strong. 


How do standard drainboards work?


Standard drainboards have a needle-punched geotextile that is glued to the dimples during production. The pressure from structural loads such as backfill or soil overburden can cause the geotextiles to stretch and move into the space, which reduces the composite membrane’s drainage rate, a drainboard’s primary performance quality. 

Standard drainboards are typically used for plaza decks, green spaces, athletic fields, roads and highways, and residential or commercial buildings.


How do drainboards protect different surfaces from water and moisture?


Here are some common applications in which a drainboard can be installed to effectively drain water from the site, preventing structural damage and leaks. 

Foundations: Foundation drainboards, known as waterproofing membranes or waterproofing drainboards, are installed on the exterior of foundation walls. They create a barrier to prevent water from infiltrating the foundation and direct water away from the building. 

Roofs: Roof drainboards are used beneath roofing materials to provide the proper slope and drainage. This is especially important for large, flat roofs and ceilings, which can be susceptible to pooling or ponding. 

Green roofs: Perfect for green spaces or leisure areas, green roof drainboard systems provide efficient drainage while supporting vegetation and greenery, allowing them to grow and thrive. 

Retaining walls: Retaining wall drainboards are installed behind retaining walls to relieve hydrostatic pressure and improve drainage. They help prevent water buildup that can cause wall failure and soil erosion.

Exterior walls: As part of the wall assembly, drainboards are used to improve moisture management and create a gap between the siding or cladding and sheathing, allowing water to drain away from the structure. 

Blind side: In installations using soil retention systems, drainboards provide critical water management and a protected application surface for subsequently applied waterproofing membranes.


Can I use a protection board along with a drainboard?


Although protection boards and drainboards are both used in building construction, they have very different purposes, functions, and characteristics. 

A protection board is used to shield building materials from damage caused by outdoor elements, physical impact, or UV rays. Using a drainboard in addition to a protection board can help extend the life of your protection board by managing water runoff and controlling moisture.


Are standard drainboards still effective as a means of water drainage?


There has always been (and will always be) a need for effective drainage. However, manufacturing processes have changed, and standard drainboard quality has decreased. In order to create more affordable drainboards, manufacturers use cheaper geotextiles, which can affect performance down the road. As a result, issues like clogging, leaks, and structural damage can occur, resulting in more headaches and costs for the architect or builder. 

Soil pressure and backfilling are also major considerations, as a cheaper drainboard may waver under excessive compression or weight. So, while these conventional drainage systems may be a typical approach, they don’t stand up to the quality and performance standards required for long-term protection.


water puddle on a concrete surface (ø porthole ) superimposed on a DELTA-TERRAXX membrane being installed


Lastly, standard drainboards can present a challenge when installing them in horizontal applications. Narrow rolls of drainboard require a lot of weighting to keep them from lifting in the wind or rolling back up. These weights can also reduce open work areas, which can lower productivity. Plus, the significantly higher amount of ballast needed to keep the drainboards steady and reduce wind uplift can increase product and labor costs. 

All of these factors are not ideal for architects and specifiers who are looking for a cost-effective solution that can still deliver building performance and quality.

They’re in luck, as there’s an innovative drainboard solution unmatched by standard drainboards that has recently entered the North American market: Dörken’s DELTA®-TERRAXX and DELTA®-TERRAXX PLUS. 


DELTA-TERRAXX (rolled-up protective and drainage sheeting) resting on top of a North American map illustration


The origin story of DELTA®-TERRAXX products


To date, DELTA®-TERRAXX products have been the leading drainboards on the market in Europe. Their innovative, unique features make them unlike any others. 

Now, Dörken is bringing both DELTA®-TERRAXX products to Canada, providing architects, specificers, and installers the opportunity to utilize a new, high-performance drainboard for all of their horizontal and vertical applications.


What makes DELTA®-TERRAXX products different from other drainboards?


Engineered for higher drainage capacity 

  • Designed with a unique composition of a dimple sheet combined with a heat-bonded TYPAR® geotextile, DELTA®-TERRAXX products maintain drainage space even under heavy compression or structural loads.
  • This added drainage capacity also prevents frost damage from freeze and thaw cycles.  
  • The unique dimpled membrane forms a 10-mm-high drainage layer, which is noticeably more efficient than a common 20- or 30-cm-thick mineral seepage layer.
  • The optimal ratio of knob structure and weight per unit area found in DELTA®-TERRAXX creates the perfect balance of compressive strength, performance, and handling/installation. This makes for a drainage capacity of 2.51 L/m2, even at an installation depth of 10 m. 


Withstands extreme compression loads 

  • DELTA®-TERRAXX products are specially designed to withstand extreme compression loads, up to 8,969 psf (429kPa; up to type-60 heavy trucks, depending on the covering).
  • Even under pressure from backfill, soil overburden, or other structural loads, the durable heat-bonded TYPAR® geotextile maintains its shape and drainage space, allowing for faster drainage, and eliminating clogging.
  • It’s also a safe option for workers to walk on any compression-resistant waterproofing layers during the construction phase, allowing contractors and installers to have confidence during installation.


Safe, fast, and easy to install 

  • DELTA®-TERRAXX PLUS has a self-adhering edge tab that simplifies installation, helping to prevent the ingress of soil particles, and provides dramatically better positional stability.
  • The sheets can also be overlapped and interconnected and require minimal ballast to keep them steady during installation.
  • It’s made from a lighter, high-density polyethylene (51 lbs/24 kg per roll) and is easier to trim and cut. 
  • It’s free of recycled material (in accordance with DIN EN 13252), and has passed rigorous tests for aging resistance by both independent and accredited testing institutes.
  • Materials testing institutes have tested the product to see how exposure to a permanent load of 20 kN/m2 over a 50-year period affects the drainage capacity. In vertical applications, the drainage sheet has an outstanding drainage capacity of 3.1 L/m2 on installation, and only slightly diminishes to 2.68 L/m2 after 50 years of exposure to a load of 20 kN/m2.
  • It can also be used in vertical blindside waterproofing down to depths of 7 stories, vertical positive side waterproofing down to depths of 3 stories, and can be used in all common horizontal waterproofing systems under typical traffic loads. 


From drainage capacity to compression strength, DELTA®-TERRAXX products are unlike any other drainboards. See how they match up to traditional drainboards in this infographic that provides a side-by-side comparison.


Dual applications mean more uses 

For architects, one of the best features of DELTA®-TERRAXX products is the design flexibility they bring. Having both horizontal and vertical capabilities opens the door for new opportunities and greater drainage protection without compromising on durability or performance. Whether you’re building a sports field, roof structure, or playground, this waterproofing drainboard is designed to keep your buildings performing well into the future.


High drainage. High protection. High performance. Get it all with DELTA®-TERRAXX products.


DELTA®-TERRAXX products are your ultimate solution for horizontal and vertical applications. With their innovative product composition, higher drainage capacity, superior durability, ability to withstand tough conditions, and the fact that they are safe, easy, and faster to install than others of their kind, these drainboards are beyond anything available in North America.

Learn more about DELTA®-TERRAXX products and how they can be used for your next building project.