Best Practices:
A Recipe for Specification Success


The old cautionary proverb about too many cooks spoiling the broth is often unfortunately ignored in modern times, when a group of individually very talented professionals collaborates to write a specification.

To illustrate this, let us use a hypothetical situation in which an engineering firm and an architectural firm design and prepare the specifications for an enclosed municipal swimming pool.

The engineering firm designs the steel supporting structure to conform to the aesthetic requirements of the architect, while providing the structural integrity required.

In this division of the specification, the engineer specifies the size, grade and structural details of the supporting members; he or she also specifies the requirements for surface preparation and shop priming of the steel structural members.

In the steel section of the specification, the engineer specifies SSPC-SP 3 Power Tool Cleaning, followed by a shop-applied coat of CISC 1-73a Primer.

Meanwhile ...

The architectural firm is also diligently working on the specification for the entire structure at this time.

The architect who is preparing the painting section refers to his MPI manual and selects a high-performance coating system for the structural steel in the pool area, in order to provide a long, low-maintenance service life for this corrosion-prone area.

© iStock / Dan Barnes

What happens when two sets of specs on structural steel end up conflicting? Nothing good.

The system chosen consists of an epoxy primer, an epoxy high-build intermediate coat, and a two-component polyurethane finish coat. This is an expensive, high-performance coating system that will provide the service life desired.

To ensure dependable performance of this system, abrasive blast cleaning to SSPC-SP 10 is wisely specified.

When the structural steel arrives on site and has been erected, the problems start to unfold. It is discovered that the shop-applied primer and surface preparation are not compatible with the coating system specified in the painting section of the specification.

Houston, We Have a Problem

At this point, there are no good choices.

If the system is applied, the primer will wrinkle and fall off. If a barrier coat can be found to protect the primer, the low level of surface preparation and the poor quality of the shop primer will almost certainly guarantee premature failure of the coating system in this wet environment.

The only satisfactory remedy appears to be to perform abrasive blast cleaning on site to remove the shop primer and achieve the level of surface preparation desired.

© iStock / korayhoylu

Midway through a project is the wrong time to review and compare all of the specs.

Who is responsible? Who will bear the additional cost?

The Cure: Prevention

Situations similar to the one described occur with alarming frequency. The solution is communication.

It is a wise policy to ensure that all related sections of a specification do not contain contradictory requirements. This can be ensured in the case of the paint system by requiring that all related sections refer to the painting section for selection of surface preparation requirements and coating materials.

Any other approach is a recipe for spoiled broth.

Editor's Note: This article was written by PQA Inspector Dave Lick and is reprinted with permission from the MPI (Master Painters Institute) newsletter. MPI content describes best practices for commercial, institutional, and light industrial painting.


Tagged categories: Architects; Coating failure; Engineers; Epoxy; Good Technical Practice; Master Painters Institute (MPI); Specification writing; Specifiers; Structural steel; Surface preparation

Join the Conversation:

Sign in to our community to add your comments.