Seal-Once Negative Pressure Waterproofer

This hydrogel waterproofs and seals the concrete surface, is a non-flammable, non-toxic, non-acid sealer that strengthens and waterproofs cementious materials. It reduces and blocks vapor emissions but still leaves the concrete breathable.

Please select options below to see price.

Reset options



What is Seal-Once Negative Pressure Waterproofer?

Seal-Once Negative Pressure Waterproofer is a silica hydrogel that reacts with the free alkali within the concrete to form a gel that fills the capillaries within the substrate and pushes out harmful chlorides. This hydrogel waterproofs and seals the concrete surface. Seal-Once Negative Pressure Waterproofer is a non-flammable, non-toxic, non-acid sealer that strengthens and waterproofs cementious materials. It reduces and blocks vapor emissions but still leaves the concrete breathable.


What Substrates is Seal-Once Negative Pressure Waterproofer designed for?

  • Poured Concrete – Basements
  • Concrete Block – Foundations
  • Parking Garages – Mortar & Stone


What are the Features offered by Seal-Once Negative Pressure Waterproofer?

  • Blocks Moisture Vapor Transfer
  • Blocks and reduces vapor emissions through concrete but leaves concrete breathable
  • Suitable for above and below grade applications
  • Safe for interior and exterior use
  • Purges soluble chlorides and prevents their reentry
  • Cures and chemically hardens in one operation
  • Does not alter bondablity of concrete
  • Contains a nonacid penetrating agent
  • Resists many acids, oils, greases and salts
  • May be used as a curing and sealing agent that reduces the “green concrete” window of 28 days down to an average of 5 days


What Surface Preparation is Needed before applying Seal-Once Negative Pressure Waterproofer?

All surfaces should be cleaned before sealing for best penetration and performance. Clean all dust, debris, and loose material. Remove oil, grease, algae, grime, mold and mildew stains with Seal-Once Concrete and Masonry Cleaner. After cleaning, test absorbency or surface by sprinkling a few drops of water on the surface. If the water does not readily penetrate the surface, stripping will be necessary. We recommend Franmar 605PRO Stripper with Safenol.


How Do You Apply Seal-Once Negative Pressure Waterproofer?

  • Shake product well before using. Do not dilute or alter Seal-Once Negative Pressure Waterproofer
  • All surfaces being treated must be pre-dampened with a light mist of water.
  • Apply Seal-Once Negative Pressure Waterproofer with a low pressure pump sprayer with a fan tip.
  • On horizontal surfaces apply in a left to right pattern overlapping 50%. After the first coat soaks in apply a second coat in an up and down pattern overlapping 50%. Avoid over application or ponding.
  • Excess unreacted material will leave white crystals on the surface.
  • On vertical surfaces apply Seal-Once Negative Pressure Waterproofer from top to bottom to the point of refusal. Apply the sealer in two even coats. After the first coat has soaked in, promptly apply a second coat.
  • On horizontal or vertical surfaces, areas that absorb sealer more quickly will require extra coats of Seal-Once Negative Pressure Waterproofer
  • On all surfaces after a second coat has soaked in, remove any excess material from surface and spray entire area with a light mist of clean water.
  • Keep treated surface dry to cure for a minimum of 12 hours, for applications with high moisture transfer allow surface to cure for 72 hours.


Seal-Once Negative Pressure Waterproofer Application Details

Application Temperature Range 40 – 95 Degrees F
Coverage Rate On Rough Slabs: 75-200 SF per GAL

On Smooth Slab: 250-300 SF per GAL

Drying Time Allow 12 Hours before Light Foot Traffic

Allow 24 Hours before Applying any topcoat or flooring



Safety Data Sheet

SDS for Seal-Once Negative Pressure WaterprooferClick here for this product’s Safety Data Sheets (SDS)


There are no reviews yet.

Be the first to review “Seal-Once Negative Pressure Waterproofer”

You may also like…