Durable Finishes for Faucets: PVD Coatings and Antimicrobial Treatments Explained
Commercial and institutional faucets have more hostile environments compared to residential faucets. Their finishes get exposed to heavy usage, repeated cycles of cleaning, disinfecting agents, and more corrosive water. As an AEC professional, it becomes very clear that a faucet finish acts as more than just an aesthetic feature. It primarily functions as a performance component, as it needs to maintain corrosion-resistant properties and should be easier on water.
The article considers physical vapor deposition coatings and antimicrobial finishes from an engineering perspective and with regard to specifications and performance characteristics.
The challenge of defining durability
Appearance should be referenced against specifications based on measurable outcomes and known modes of failure, not against requirements related to duration.
The common failures that occur on finishes include delamination at corners and penetrations caused by coatings, micro-scratches due to daily wipe-downs, pitting due to contact with chlorides, tarnish due to the use of oxidizing cleaners, and corrosion beneath film due to trapped moisture at joints. A finish might succeed on subsequent lab testing but fail prematurely if there is no compatibility among the three.
Regarding architects and engineers, it relates to reliable performance within actual maintenance conditions for a given type of occupancy use, which would be healthcare, education, transportation, and so on.
PVD coatings and performance properties
Physical vapor deposition:
Physical Vapor Deposition is a vacuum technique for applying thin layers of ceramic materials or metal-ceramic materials like titanium nitride, zirconium nitride, and chromium nitride. These materials have more hardness compared to electroplated materials.
Important for specifying PVD finishes as a whole: PVD finishes are more systems than single-component layers. Their performance ranges from substrate materials, preparation, and adhesives to functional coatings and topping coats. Poor preparation and uniformity are more often cited as problems with PVD fabrication in relation to failures rather than limitations on PVD as a method.
Submittal document(s) required for
When evaluating submittals, it should be specified that testing data referencing recognized standards, and not proprietary scales, should be provided. Some commonly referenced standards include corrosion resilience standards B117 at ASTM B117 and ASTM D3359 for coating adhesion at ASTM Some manufacturers also cite “ISO 9227 Corrosion tests in artificial atmospheres — Test methods and general requirements” for corrosion testing.
Secondly, it must be documented which cleaners and disinfectants have been cleared with that particular finish. Numerous failures can be traced back to contact with chemicals beyond what the manufacturer has tested.
Substrate choice and compliance with potable water standards:
The finish deterioration cannot be assessed apart from the faucet and wetted materials. Should there be deterioration on the finish, it will have to be acceptable for contact with drinking water and resist corrosion given the project water conditions.
Requirements may include NSF/ANSI 61 compliance for drinking water system components, as detailed at NSF/ANSI knowledge library
B167 and NSF ANSI 372 for lead, with reference materials available at ANSI Webstore preview pages.
From a risk management perspective, materials like stainless steel may provide an additional degree of robustness within hostile environments, even with PVD finishes.
Antimicrobial therapies and realistic expectations
Antimicrobial finishes have often been misrepresented and, at times, exaggerated. From a technical perspective, it would be highly desirable to differentiate between finishes that are meant for protecting materials and any reduction of pathogens on contact surfaces.
Topics related to antimicrobial treated articles in the United States are governed by EPA guidelines that relate to FIFRA. EPA Pesticide Registration Notice 2000-1 describes the exemption related to treated articles and can be accessed at EPA PRN 2000-1
Antimicrobial efficacy can be specified, and it should be mandatory that these specifications be proven via normalized testing and well-defined limits. ISO 22196 is widely referenced as a method of testing antibacterial activity on non-porous materials, and normalized information ISO 22196.
Regarding AEC, it should be pointed out that antimicrobial agents cannot be considered as an alternative to conventional cleaners. Cleaning efficacy, compatibility, and crevice-free functionality are still more decisive factors.
Sustainability and Lifecycle Analysis
Durable finishes promote sustainability because they eliminate the need for replacement and reduce the usage and generation of harsh chemicals for cleaning.
Water efficiency alignment
Commercial bathroom faucets sold within various jurisdictions are mandated based on EPA WaterSense specifications. WaterSense Product Specification Resources can be accessed at EPA WaterSense product specifications, criteria specific to faucets and published at EPA
Although finish type does not impact flow rate, it will affect the longevity of sensor lenses, aerators, and outlet faces. A scale-resistant and chemically resistant finish will allow better preservation of designed flow rates.
CALGreen considerations
Water efficiency requirements are common California project needs involving CALGreen. General CALGreen resources are provided at CALGreen resources
- with code language available via ICC resources at ICC codes
Even beyond California, there are institutional owners who have incorporated CALGreen compliance into voluntarily adopted sustainability standards.
ACCESSIBILITY IMPACT
ADA compliance primarily considers operationality, reachable ranges, and control forces, but surface finishes have some effects on accessibility. Those finishes that become degraded or turn rough with age might result in increased control forces or sensor problems.
Finishes for sensor-activated faucets should be specified so as not to glare, leave residues, or deteriorate, potentially interfering with sensor accuracy.finish materials with particular finishes.
Baseline performance standards for faucets
Commercial specifications usually refer to ASME A112.18.1 and CSA B125.1 standards. A brief overview on ASME standards can be viewed at ASME codes and standards. Using an anchoring finish tied to a fixture that meets acceptable standards for mechanical and durability criteria will help prevent deficiencies in the base fitting from affecting the performance characteristics of the finish.
Integration with facility operations
Finishes used within an institutional setting need to relate to the maintenance methods and utilization practices. It needs to be specified that there be a record relating to acceptable cleaners, replacement components, and identification for finishes. Where projects have centralized maintenance or smart restrooms, finish care data should be provided in a form useful to facilities staff, not just in marketing materials.
Composing enforceable end specifications
To make these requirements specific and enforceable, it should include specifications for submittals and performance. These usually include specifications for PVD coating systems and materials, performance verification based on recognized standards via report references, disinfectant compatibility, and compliance with ASME, WaterSense, CALGreen, and NSF standards as necessary. When finishes are viewed within an integrated system as opposed to stand-alone aesthetic components, they have a better chance at providing the longevity and predictability required for commercial and institutional projects.
| Performance criterion | PVD relative score (1–10) | What it means for AEC specs in commercial settings |
|---|---|---|
| Abrasion resistance | 9 | Better resistance to daily wipe down, incidental impact, and micro scratching from routine cleaning. |
| Corrosion resistance | 9 | Stronger barrier behavior in humid restrooms and near chloride exposure, especially at edges and joints when properly prepped. |
| Chemical resistance | 8 | Generally tolerant of common disinfectants, but still requires verified compatibility lists for oxidizers, acids, and high concentration cleaners. |
| Adhesion durability | 8 | Dependent on substrate prep and geometry. Edge radii, penetrations, and sensor windows are common risk areas. |
| Lifecycle longevity | 9 | Lower likelihood of early finish failure reduces replacement cycles and maintenance disruptions in institutional facilities. |
