Per plans and specs

Architects originate plans and specifications that legally bind contractor and subcontractors to a set of standards to be followed in the subsequent construction of a project. However, in our experience, most projects have inappropriate specifications that do not apply to the project or to the recommended products. All specifications should be applicable and legally binding; so in our subcontracts, we take exception to those anomalies that will conflict with the project, the products or the methods of this subcontractor. The following discussion illustrates examples of problematic glazing specifications we have encountered, followed by recommendations for change.

Specifications for product performance

From our experience this group of specifications is often generic with one or more specifications not appropriate for the project or the products.

Example 1 is specifications written for impact projects when it is a non-impact project. We have also seen the reverse situation.

Example 2 is a specification written around AAMA 1503 that refers to condensation limitations but the project at hand does not have insulating glass, which is a fundamental requirement for the restriction of condensation.

Example 3 is generic standards but the recommended products have not been subjected to the following tests:  a) AAMA 501.1 Dynamic Pressure Water Resistance testing b) AAMA 501.4 Interstory Drift.

Example 4 is generic standards but the project does not require them nor have the products been so tested: AAMA 501.5 Thermal Cycling, AAMA 501.6 Seismic Performance, AAMA 1801 Acoustic Performance.

Example 5 is secondary water requirements that require a one-directional gate that allows water to exit from the interior to the exterior but closes against water entering from the exterior to the interior. Again, a specification is inserted with no recommended product capable of meeting the specification.

Example 6 is Leadership in energy and Environmental Design requirements for glazing products regarding local sourcing of materials and recycling of materials. The criteria for meeting these specifications have varied in interpretation from project to project. If the specifications of localized materials and recycled materials are strictly interpreted, none of the glazing products fully comply.

Example 7 is specifications that inappropriately require "bracing the primary building structure where required to provide support for forces imposed by work of this section."

Specifications for materials
Certain material specifications are required to further clarify certain features, e.g. stainless steel screws, or certain dimensional requirement, e.g. 3-inch depth. However, we have encountered material restrictions on the thickness of the metal used to make the window, the types of screws, the type of weather seal or vinyl, etc. In most cases, the material parts are included in the same assembly that meets various performance standards. At worst, a material specification is a signal that the specification originated from a vendor that is inserting a unique feature of its product not available in other products. At best, these material specifications might be unintentionally in conflict with performance specifications.

Example 8 is a specification for the metal thickness of the window or storefront to be 1/8 inch. This specification might eliminate products that have already met performance specifications because one of the extrusions is less than 1/8 inch.

Example 9 is specifications that impose a requirement for glazing products to use membranes or flashing, not part of the manufacturer's tested assembly. In certain applications, the surrounding material requires membranes or flashing to assist with the water resistance. In other cases, specified flashing is added to enhance the glazing product's performance; but this results in an untested assembly and possible voiding of the warranty. In all cases, these products are introducing a non-tested element around the tested glazing product. The warranty for these mem- branes and flashings is not included under the manufacturer's warranty but is limited to the installer's warranty.

Example 10 is specifications designed to enhance the tested glazing assembly; for example, to add "walk blocks" into the glazing pocket.  The problem is that the manufacturer used in this project did not have "walk blocks."

Specifications for product installation
We have encountered a number of specifications that restrict the type of installation company or limit the installation tolerances. 

Example 11 is specifications that require the installation company's glaziers to pass a national glazing test. At this time there does not appear to be a nationally recognized glazing test nor do state or local agencies require such testing. Until this testing becomes more common, it should not be included in specifications.

Example 12 is specifications biased toward a union sponsored training program that would tend to limit competitive bidding.

Example 13 is specifications biased toward minority participation. The resulting subcontracts often do not achieve the intended diversity but result in higher prices or lower quality.

Example 14 is specifications on installation tolerances. They either create new industry tolerances or duplicate existing AAMA installation standards. In either case, it should not be necessary to review and/or challenge such details rather than referring to available standards.

Example 15 is specifications for "field measure" or "field verify" prior to fabrication; these are a problem. These standards are typically in conflict with the schedule. Whenever contractors refuse or are unable to furnish guaranteed openings, scheduling conflicts result with glass manufacturers unable to comply with the "as needed" contractor demand. The result is an unhappy contractor. In most projects, the demands of the schedule make this an unrealistic specification.

Specifications for protection and warranties
Example 16 is specifications found in most projects that require the subcontractor to "protect" the product until the owner takes possession at the end of the project. In some instances, protection is confused with the application of Blue Maxx or vinyl. In most cases, protection is further complicated in the subcontract by adding a clause that the subcontractor must pay for the deductibles of a builder's risk insurance policy.  The American Architectural Manufacturers Association, Schaumburg, Ill., indicates that protection is not a function of the subcon-tractor. We have been involved in two projects that had vandalism, plus numerous projects where welders and glass cleaners damaged installed products. From a practical side, it is impossible for a subcontractor to protect an installed product against damages by other trades, vandals or weather effects, and his insurance does not cover such damages. Therefore, this specification should not be included.

Example 17 is specifications for warranties that do not match the specified products. For example, we have seen 10-year warranty requirements for an AAMA 611 Class II anodized finish. This is an interior finish and generally carries a one year warranty. We have seen 10-year warranties on laminated products that generally are limited to five years.

Specifications for quality control
Example 18 is a storefront specification that specified a laboratory water test of 15 psf and a field water test of 10 psf. The first problem: the specification section had several recommended storefront systems, none of which were tested to 15 psf in the laboratory nor certified by the manufactures at 10 psf in the field. The second problem: it did not base the calculation on the industry standard, AAMA 503, which would have based the laboratory requirement on 20 percent of the project design pressure and the field test on 2/3 of that number. Using the AAMA recommendation would have reduced the field water test to 8 psf, which was acceptable to the manufacturers.

Example 19 is a window specification that specified an HC90 window for a project with a 60 psf design pressure, a 15 psf laboratory water test and a 10 psf field water test. The problem with the specification was none of the awning windows complied with the HC90 rating. In the case of water testing, there are two problems: first, the window is overrated for the project and second, the industry test standard, AAMA 502, formulas are side-stepped.  Even accepting the HC90 rating, AAMA 502 would have set the field test standard at 9 psf but a properly rated window would have lowered the standard further.

Example 20 includes several specifications that either do not reference the AAMA water test standards or reference the wrong test standards.  We have seen specifications refer to AAMA 501.2, a hose test, tied to the application of ASTM 1105 which is the chamber test procedures used in AAMA 502 and AAMA 503. Field test specifications refer to AAMA 501.1, a dynamic water test applied in a laboratory but often not tested by the recommended products.

Recommendations
Short-term: Subcontractors need to contractually void specifications that do not apply to a project or to the product they intend to use. Unfortunately, for the subcontractor, this places the burden on them to identify anomalies that will cause problems for the project. This also presents a problem for the general contractor since they might have accepted the project "per plans and specifications." Subcontractor requested modifications might run the gauntlet of the general contractor, the architect and sometimes the owner before everyone can agree to the changes.

Long-term: Specifications need to be customized for the project and the products. Along this line we suggest:
A "reasonableness test" that no specification applies that is not satisfied by at least one recommended product. In the case of public projects there should be three such products.

Performance specifications for product assemblies should eliminate the need to further specify materials that were tested in those assemblies.

Specifications for warranties cannot exceed the manufacturer's standard warranty durations.

Specifications for non-tested products such as membranes and flashings may be added to enhance surrounding materials but not to enhance the performance of the tested glazing product.

Installation specifications should be based on industry installation standards and performance schedules rather than on organizational composition.

Protection specifications should be eliminated for the subcontractor.

The vast majority of specifications are appropriate to the project and the products. This discussion centers on specifications that should be modified in order for the project to be built 100 percent per plans and specifications.