Waterproofing compound WS

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Product description

Fescon Waterproofing Compound WS is a fast-drying, single-component indoor waterproofing compound that can be rolled or sprayed. Suitable for the waterproofing of floors and walls.   

The 12-litre package will be available in early 2025 and will replace the 15-litre package in the future. In the manufacture of the 12-litre container, we use recycled plastic. In addition, the package is easier to handle.

  • Consumption about 0.7 l/m2 on walls and floors
  • Sufficient dry membrane thickness easily with two treatments
  • Extremely elastic
  • Can also be sprayed
  • M1 and EC1 rated
  • Certificate No. C-12511-18

Applications

  • Waterproofing of indoor walls and floors to be tiled.
  • For the treatment of interior concrete element seams in apartment and public buildings, to prevent cracks in the completed interior surface
  • The substrate can be concrete, lightweight concrete, a cement-based filler or building board suitable for wet rooms
The product is listed in the portal for building products that can be used in Nordic Swan Ecolabelled buildings.
GTIN code Product name Product number Package size
6416841769091 WATERPROOFING COMPOUND WS 3 L / 4.5 KG 76909 3 l (4,5 kg)
6416841769145 WATERPROOFING COMPOUND WS 12 l / 18 KG 76914 12 l (18 kg)
6416841769121 WATERPROOFING COMPOUND WS 15 l / 22.5. KG 76912 15 l (22,5 kg)

Base

  • The substrate can be concrete, lightweight concrete, a cement-based filler or building board suitable for wet rooms
  • The substrate must be clean, solid, dust-free and vacuum-cleaned. The substrate must be solid and immobile.
  • Loose layers, cement paste and any other impurities have been removed mechanically to ensure adhesion between the product and the substrate.
  • The substrate temperature is more than +10°C and the relative humidity less than 90%.
  • Underfloor heating must be turned off two days before waterproofing.
  • Uneven floors are levelled with Fescon floor levelling plasters, and the walls with Fescon Levelling compound for wet areas WTT

Priming

  • Priming is done with Fescon Primer KP, following the instructions in the product card. 
  • Concrete substrates and cement-based filler substrates: 1 part Fescon Primer KP, 3 parts water.
  • Substrates that do not tolerate moisture, such as gypsum-based building boards: Not to be thinned. 
  • Fescon Primer KP is spread thinly with a brush. Fescon Primer KP must not be applied so much that it creates puddles. 
  • Two treatments for highly absorbent substrates (such as concrete floors cast on site).  
  • Fescon Primer KP must be dry before Waterproofing compound WS is applied, requiring 1–4 hours, depending on the conditions.

Mixing and application

  • Use the following accessories with Waterproofing compound WS: Drain flange KL-B, Waterproofing accessories (FS and VE series) and Waterproofing strip 0.15 x 25 m fibre.
  • The through-hole flange must be one size smaller than the hole to be waterproofed.
  • Waterproofing compound WS is always applied with two different treatments
  • Waterproofing compound WS is mixed before use. 
  • Waterproofing starts from the walls by applying Primer KP according to the priming instructions
  • Spread Waterproofing compound WS into the corners, where two elements meet and into through-holes. Waterproofing accessories compatible with the system are attached to the wet waterproofing compound. Spread the waterproofing compound thoroughly over the strengthening strips using a brush or roller. Make sure that the strips are fully attached to the waterproofing compound below, with no exposed parts. The strengthening strips must be between two waterproofing compound layers.
  • Apply the first layer of Waterproofing compound WS across the entire wall area to be waterproofed. The second layer may be applied about 2–3 hours later. Waterproofing compound WS changes colour as it dries. The surfaces must be dry before the next layer.
  • Begin waterproofing the floor. Spread Waterproofing compound WS into the wall and floor corners, where two elements meet. Attach reinforcements to these locations with a roller or brush. Ensure that the reinforcements are completely covered by Waterproofing compound WS.
  • Tile the walls before waterproofing the floor. Complete the bottom row of tiles when you start working on the floor tiles.
  • Start the floor waterproofing by priming the floor according to the primer product’s instructions. 
  • Spread Waterproofing compound WS into the corners and into through-holes. Waterproofing accessories compatible with the system are attached to the wet waterproofing compound. Spread the waterproofing compound thoroughly over the strengthening strips using a brush or roller. Make sure that the strips are fully attached to the waterproofing compound below, with no exposed parts. The strengthening strips must be between two waterproofing compound layers.
  • Install drain flange KL-B over the drain, on dried primer. First remove half of the protective paper and attach it to half of the drain. Remove the other half of the protective paper and turn the other half of the drain flange against the drain. The drain must be fully covered by the drain flange. Make sure that the drain flange is fully attached. Spread the waterproofing compound all over drain flange KL-B. Do NOT apply the waterproofing compound under the drain flange. 
  • Apply the first layer of the waterproofing compound across the entire floor area to be waterproofed. Allow the first layer to dry for about 2–3 hours before installing the floor drain clamping ring and applying the second layer.  
  • Install the clamping ring. Start by cutting a round role in the middle, 40 mm smaller than the drain’s diameter. Fold and tighten drain flange KL-B using the clamping ring against the inside of the drain, pressing evenly. The drain flange must reach all the way down to the bottom edge of the clamping ring when the ring is fully installed. Cut any excess parts off the bottom. 
  • Apply Waterproofing compound WS on the floor area to be waterproofed for a second time. The second layer of the waterproofing compound extends to the top edge of the clamping ring.  
  • No waterproofing compound is to be applied inside the floor drain.

Tiling

  • Tiling can be started about 5 hours after the last layer of waterproofing compound has been applied. 
  • Use Fescon tile adhesive plaster VSL, ILL, SS2 or SSL Lite, depending on the tile and target. 
  • If any waterproofing compound is visible between the clamping ring and floor drain cover, cover it over with adhesive plaster to protect it. 
  • Tiles can be grouted with Fescon Tile seaming plaster SML and sanitary silicone, following the instructions for the adhesive plaster.

Other considerations

  • The tools can be washed with water directly after use.
  • Waterproofing is carried out in accordance with RT cards and RIL guidelines. 
  • The drying times in the product card apply to +20°C, relative humidity 50%. Low temperature or high humidity in the work area extend the drying period.  
  • Through-holes can also be made using waterproofing strip 0.15 x 25 m or waterproofing membrane
  • The product will dry enough to walk on within about 2–3 hours. 
  • Avoid walking on a recently waterproofed floor.
  • Waterproofing compound WS is not suited for outdoor use, such as balconies. Similarly, the product cannot be used is locations in which the waterproofed spaces may freeze, such as outdoor saunas without continuous heating. For such locations, use Fescon Fescoseal A+B two-component waterproofing compound. 
  • Waterproofing compound WS is not suitable for spaces continuously exposed to water, such as swimming pools

Storage and handling of waste
See the separate storage and disposal instructions https://www.fescon.fi/en/material-bank

Material usage

Walls and floor: approx. 0.7 l/m2  (min. 1,0 kg/m2)

Water requirement Ready-to-use product
Type Gelatinous liquid
Colour Light blue, darkens when drying
Package size 3 l / 4,5 kg, 12 l / 18 kg and 15 l / 22,5 kg. Packed in a plastic container.
Storage

For 12 months from the manufacturing date shown on the package, store in a warm place. The product must not freeze.

Density

1 l = 1.5 kg

Usage temperature

+10°C...25°C (platform and internal temperature) 

Drying time

About 2–3 hours first treatment. After second treatment, about 5 hours before installing tiles (+20 °C, relative humidity 50%).

Coatable Tiles may be installed after a second treatment, after about 5 hours
Frost resistance Not frost resistant
Film thickness Min. 0,5 mm (both walls and floors)
Method of application Brush, roller or spray
Transport Warm transport
Limitation of liability, product use notes and restrictions: Please familiarize yourself with Fescon Oy's general terms of delivery and the design and work instructions related to the product.