20+ years in business
We at Primostar have been working with waterproofing solutions for over twenty years. We sell and produce waterproofing materials to below-grade reinforced concrete structures. We also have 20 years of experience in installing these materials.
Over the years, we have seen how the market has moved from using older classical membrane waterproofing materials, the Black Tank method, to a new, more modern and greener version, the White Tank method.
Black Tank method
White Tank method
Figure 1: Concrete slab foundation and basement wall construction joint waterproofing. Two watertight membranes are used for this Black Tank method.
A Black Tank is a waterproofing system in which the underground surface of a building is pre-insulated with a watertight membrane before the concrete is poured. After casting the structure’s concrete, the walls and inverted roofs are waterproofed with an adhesive watertight membrane.
A White Tank is a waterproofing system that uses concrete mixtures with a waterproof admixture. In addition, when using the White Tank method, water resistance must be ensured in all work joints, for example, by using WPM construction joint profiles.
The black tank solution for membrane waterproofing has higher material and labor costs than the white tank method.
White tank method
The white tank method consists of three parts, the first of which is the crystalline admixture that is added to the concrete mixture in the concrete assembly. Secondly, construction joint profiles, are added to concrete joints before casting. And thirdly, we can use the Crack Inducer Profile, to pour larger volumes of concrete at once.
The picture shows how the joint profile WPM Sealing Element 125L BIT (custom-made product) remains in the tile foundation, making the joint between the tile foundation and the wall waterproof.
The constant challenge for the construction industry is to do more in less time and at a lower cost.
The most significant pressure on prices in Estonia was during the previous crisis in 2009-2010 when builders wanted new, lower-priced solutions.
We met the market’s demands by replacing the “classic” bituminous or artificial materials-based waterproofing materials with a crystalline admixture which is added to the concrete mix at the factory. Since 2009, we have been offering a complete waterproofing solution with crystalline additive and other products in this system, including construction and deformation joint profiles, on large construction sites.
In this way, we have offered a complete waterproofing solution for underground, reinforced concrete structures at least half cheaper than before.
The crystalline admixture gives the concrete a self-healing ability. Together with the water entering the crack, the admixture can close the static cracks in the concrete with an opening width of less than 0.4 mm.
Picture 1: Concrete before and after contact with water (~ 14 days). Waterproofing of concrete structures with crystalline admixture.
When the gap is under constant dynamic load, i.e., moving constantly, the admixture that increases the water resistance on the concrete cannot fill cracks with an opening greater than 0.4mm.
Construction joint profiles
When engineers calculate 0.2… 0.3mm shrinkage to the reinforced concrete structure in the construction design, then, in reality, it may still happen that the resulting cracks open more than 0.4 mm and do not grow together.
While working on various projects, we saw that non-watertight cracks still appeared on occasion. Therefore, a working solution had to be found. In 2018, we started the production of various watertight profiles in Estonia with WPMEstonia OÜ, which enabled us to solve the problem described above.
Our product range includes waterproof sheet metal profiles installed in joints, either in roll or sheet profile. Secondly, we offer watertight mesh and sheet metal “Stop-End profiles” for slab foundation joints.
We have also created a solution for controlling the shrinkage of reinforced concrete structures so that the crack is immediately waterproof at the desired location. The solution is the WPM Crack Inducer profile. This profile is designed so that the resulting crack is pin-shaped in the cross-section of the structure. The pin-shaped crack does not reduce the strength of the structure significantly, in which case we can create such a crack in the load-bearing structures.
WPM Crack Inducer
pin-shaped crack that is instantly waterproof. Waterproofing solution with joint profiles and crystalline additive.
We use the WPM Crack Inducer profile with a fixed step according to the reinforcement in the structure and the thickness of the structure.
Paavo Pikandi, the designer of the CIVEN design bureau, and Indrek Uusalu, the head of WPMEstonia and Primostar, talk about how to control the shrinkage of concrete.
Thanks to WPMEstonia profiles and crystalline admixture, the waterproofing of concrete structures is significantly faster, cheaper, and more environmentally friendly.
If you want to know if and how we can make your concrete structures waterproof and speed up the casting process with the white tank method, then contact us, and we will review the project together.