Andrea Wells
Director, Marketing & Communications

July 16, 2019


New Mandatory Supplemental Language Included

(ALEXANDRIA, VA)—The Pool & Hot Tub Alliance (PHTA) announced today that a supplement to the ANSI/APSP/ICC/NPC-12 2016 Standard for the Plastering of Swimming Pools and Spas was approved by the American National Standards Institute (ANSI) on May 10, 2019.  The new supplement impacts the way that industry professionals plaster pools and spas.  

“We are excited that our PHTA Standard Writing Committee (SWC) for the Plastering of Pools & Spas was able to address plastering applications in cold temperatures and further explain their rationale for those changes in the non-mandatory section of the publication,” said PHTA Director of Standards Promotion and Adoption, Susan Hilaski. “Volunteer subject matter experts who specialize in plastering provided more clarity on this issue and introduced a guide to cold weather concreting.”

The ANSI/APSP/ICC/NPC-12 2016 Standard for the Plastering of Swimming Pools and Spas is the industry standard for plastering of cementitious finish coatings for inground swimming pools or other cementitious water-containment vessels covering both material and application. 

The new supplement contains mandatory information and the appendix provides recommended changes that impact the plastering of swimming pools and spas. Main revisions include:  

  • Mandatory: 
    Clarification on the cold weather plastering application temperature allowance. 
  • Recommended: 
    Clarification on the water: cementitious materials (w/cm) ratio allowance.
    Clarification on the usage of calcium chloride (set accelerant) allowance.

Download Supplement A. Individuals that purchase the ANSI/APSP/ICC/NPC-12 2016 Standard for the Plastering of Swimming Pools and Spas will receive the ‘Supplement A’ revisions which are noted in the beginning pages of the standard. 

“Working towards industry excellence starts by delivering quality products, and this Standard gives guidance on stipulating, or ‘setting the bar’, to ensure the quality of workmanship, materials, and safety based on commonly-accepted trade practice,” said PHTA-12 Standard Writing Committee Chairman Jonathan Dongell. “The new supplement, and additional non-mandatory information, provide greater clarification to the existing Standard.”

This standard is now available for purchase. Order your copy at For more information, email PHTA Director of Standards and Adoption, Susan Hilaski at


About PHTA
The Pool & Hot Tub Alliance was formed in 2019, combining the Association of Pool & Spa Professionals (APSP) and the National Swimming Pool Foundation (NSPF). With the mission to “Celebrate the Water,” PHTA facilitates the expansion of swimming, water safety and related research and outreach activities aimed at introducing more people to swimming, making swimming environments safer and keeping pools open to serve communities. For more information, visit or