Frequently Asked Questions (FAQ)

What is the Krystol T1 mixture rate?

Krystol T1 mixture rate is approximately 3.5 parts of the powder to 1 part clean water by volume to produce a thick low sag, but spreadable coating. Mix ratio may slightly vary based on ambient conditions and if the product is being applied to the concrete by sprayer or by brush.

Can I apply Krystol T1 in a single coat?

Yes, Krystol T1 can be installed in either one or two coats. A single thick coat, using a coverage of 1.2 kg/m2, can be applied to concrete and can save time.

Can I paint over Krystol T1?

Yes, paints and coatings must be suitable for use on (new) concrete and can be applied according to the paint manufacturer’s instructions, including any recommended primers. Cementitious products, such as grouts, mortars and plasters can also be applied after Krystol T1 has set hard and has developed enough bond for bon strength to support these products. If installing after this time, use a polymer bonding agent. Always apply a test patch to determine compatibility.

How long should Krystol T1 cure before back filling with soil?

Backfilling may be done after Krystol T1 has set hard, which typically takes 24 hours. Always inspect to ensure adequate strength and a sound bond. If backfilling within 3 days, use damp backfill material so as to not draw moisture out of the coating.

Why is my application of Krystol T1 flaking off?

Krystol T1 requires surface preparation, including the concrete to be in a Surface Saturated Dry (SSD) when it is applied as well as proper application conditions and moist curing. When installed properly (see Application Instruction 2.11 and/or 5.12), Krystol T1 will gain most of its strength and adhesion between 1 and 7 days depending on curing conditions. If early strength and adhesion seems low, continue to moist cure the Krystol T1 application to facilitate further hydration until the desired properties develop.

Why do I need to apply a layer of mortar over the Krystol T1 when installing under tile?

Applying an additional layer of mortar over Krystol T1 prior to installing tile has several advantages; the mortar allows the surface profile to be modified to suit the tile installer’s preference, and it also provides a fresh surface for the tile adhesive to bond to.

What are the minimum and maximum application temperatures for Krystol T1?

Krystol T1 should not be applied below 5 °C (45 °F) to avoid long set times and the risk of freezing. In hot weather, Krystol T1 should be protected from sources of rapid evaporation such as high temperatures, direct sun exposure, low relative humidity and wind.

Can KIM, Krystol T1 or Krystol Broadcast be substituted for one another?


While each product contains the same Krystol waterproofing technology, each product has been optimized for its intended application method. Always follow the instructions found in Kryton’s product data sheets and application instructions.

What effect does KIM and Krystol T1 have on moisture vapour transmission? Does it have a perm rating (g/m2/24hrs)?

Vapour permeability ratings are applicable to membrane systems, not integral materials like KIM or Krystol T1. KIM and Krystol T1 will reduce vapour permeability and moisture vapour transmission through concrete; however, the final performance will depend on many factors, including the basic properties of the concrete.

Testing performed by the British Board of Agrément demonstrated a 20% reduction in moisture vapour permeability for KIM concrete compared to a control. The actual reduction in moisture vapour emission through concrete may be greater because KIM will block liquid water from passing through the concrete, disrupting a significant source of moisture transfer.