MasterSeal 550 is an acrylic-modified, Portland cement-based flexible waterproofing membrane for concrete and masonry. Use it above or below grade on interior or exterior surfaces. 

Product Highlights

  • Waterproof membrane protects against soil moisture and water seepage; extends life of structural slabs and underlayments

  • Creates a flexible membrane that accommodates substrate movement; prevents cracks from telegraphing; provides excellent underlayment for thin-set tile applications

  • Breathable. Allows interior moisture vapor to escape

  • Ready-to-use kit, easy to mix and place

  • Low VOCs, environmentally friendly; low odor 


  • Walls and floors

  • Tiled pools and fountains Plaza decks

  • Balconies

  • Mechanical rooms