A successful specification recipe?
The engineering firm designs the steel supporting structure to conform to the aesthetical 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, and 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 1-73 Primer.
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. The system chosen consists of an epoxy primer, an epoxy high build intermediate coat, followed by 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 is 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.
Who is responsible? Who will bear the additional cost?
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.