• High Performance Features
  • Smooth or Textured Finishes
  • Acrylic High Build Block Filler Primer
  • Ceramic Insulating and Soundproofing
  • High Pigment Concentration Provides Excellent Filling and Sealing of the Surface
  • Available in White or Grey
  • Low V.O.C. & Environmentally Friendly
  • Easy Application and Water Clean Up
Data Sheet - NWX BLOCK FILLER™ Heavy Bodied Block Sealer Primer Datasheet

People Also Ask

NWX BLOCK FILLER™ is a high-build acrylic ceramic block filler and primer designed to fill pores, pinholes, and surface imperfections in concrete block, masonry, stucco, brick, and other porous substrates. It seals the surface and creates a smooth, uniform base that improves the appearance and adhesion of the finish coat while helping extend the life of the coating system.

If you're painting new or highly porous concrete block, masonry, or stucco, using a block filler is strongly recommended. Porous masonry can absorb large amounts of paint, resulting in uneven coverage and pinholes. NWX BLOCK FILLER™ fills these voids, reduces paint absorption, and helps produce a smoother, longer-lasting finish with fewer finish coats required.

NWX BLOCK FILLER™ is designed for use on a wide variety of properly prepared surfaces, including: Concrete block (CMU), Masonry, Stucco, Brick, Cement, Adobe, Concrete slabs, Wood, Primed metal, Other properly prepared construction substrates. It is suitable for residential, commercial, and industrial projects, including new construction and renovation work.

Yes. NWX BLOCK FILLER™ is available in both smooth (non-textured) and textured finishes. The smooth version creates a more uniform surface for decorative coatings, while the textured version helps hide masonry imperfections and can be applied with hopper spray equipment for a consistent texture. It is also available in white or gray to suit different project requirements.

Yes. After NWX BLOCK FILLER™ has dried (typically a minimum of 4 hours under normal conditions), it can be top coated with compatible exterior paints and elastomeric wall coatings. The high-build primer creates a tightly bonded, sealed surface that helps improve finish coat adhesion, appearance, and long-term durability.

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USA Manufactured Since 1964

Over 60 years of quality and innovation

PROUDLY MADE IN THE USA

Manufactured with premium raw materials

RESIDENTIAL COMMERCIAL INDUSTRIAL

Solutions for every type of building

TRUSTED BY CUSTOMERS WORLDWIDE

Proven performance in all climates

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