Whether you need to keep water in or out, Sika’s Watertight Concrete solutions can help keep your structures from leaking or dry. It all starts from proper mix design and consideration of the environment that the concrete will be exposed to. View Product info.

Steps to high quality Watertight Concrete:

  • Utilize water/cement ratio ≤ 0.42 and high range water reducer (HRWR)
  • Include the use of an integral watertight admixture
  • Design low shrinkage concrete and prevent drying shrinkage cracks
  • Consider the environment & materials, utilize corrosion control and/or ASR Control if necessary
  • Utilize SCC to ensure good consolidation in general and around waterstop
Step 1 – Utilize ViscoCrete HRWR

The use of a high range water reducer allows the use of lower water/cement ratio mixes and maintains ease of placement. At lower w/c the porosity of concrete is greatly reduced making the possible ingress of water more difficult.

Step 2 - Integral Watertight Admixture

Sika’s first product over 100 year ago, Sika 1, was a product utilized to make concrete watertight. Sika now has a full range of integral watertight admixtures.

Sika 1+

Sika 1+ is liquid hydrophobic integral admixture that reduces the permeability of concrete. The product reacts with calcium ions to produce a hydrophobic layer within the capillary pores and blocks them.

Sika Watertight Concrete Powder (WTP)

Sika Watertight Powder is a dual action hydrophobic water repellent and water reducer in one with a simple dosage of just 2.95 lbs/CY .

Sika WT-215P - Crystalline

Sika WT-215P is a crystalline based watertight  integral admixture that has crack bridging capabilities.

Step 3 – Control Shrinkage

Concrete shrinks! Over time through chemical and drying shrinkage concrete changes volume and these volume changes can cause it to crack. Cracked concrete is definitely not watertight!

Shrinkage Reducing Admixture

The use of Sika Control SRA’s can help prevent cracking and reduce shrinkage.

Concrete Fibers

The use of fibers in concrete can help to limit cracking due to plastic shrinkage.

Step 4 – Consider the Concrete Environment

When designing concrete that must be watertight the environment that the concrete will be subject to must be considered. For example, it may be necessary to take steps to improve the long term durability of the concrete and utilize Sika CNI if it will be subject to chloride ions ingress.

Step 5 – Consider the use of SCC

The use of Self Consolidating Concrete is optimal for making a concrete structure watertight. Anytime the concrete does not consolidate well in forms and around waterstop, there is a change for water ingress.