Technical Procedures Disclaimer
Prior to inclusion in GSA’s library of procedures, documents are reviewed by one or more qualified preservation specialists for general consistency with the Secretary of Interior Standards for rehabilitating historic buildings as understood at the time the procedure is added to the library. All specifications require project-specific editing and professional judgement regarding the applicability of a procedure to a particular building, project or location. References to products and suppliers are to serve as a general guideline and do not constitute a federal endorsement or determination that a product or method is the best or most current alternative, remains available, or is compliant with current environmental regulations and safety standards. The library of procedures is intended to serve as a resource, not a substitute, for specification development by a qualified preservation professional.
We’ve reviewed these procedures for general consistency with federal standards for rehabilitating historic buildings and provide them only as a reference. Specifications should only be applied under the guidance of a qualified preservation professional who can assess the applicability of a procedure to a particular building, project or location. References to products and suppliers serve as general guidelines and do not constitute a federal endorsement nor a determination that a product or method is the best alternative or compliant with current environmental regulations and safety standards.
PREFACE: Before proceeding with the work in this procedure, carefully review procedure 10296-01-s which describes the advantages and disadvantages of the most common types of bird deterrent systems used on buildings. All methods of bird control have limited effectiveness, making the selection of a system difficult. Specific factors, including climate, building location, and bird species must be carefully considered in order to select the most appropriate system. All bird deterrent systems are temporary solutions to a problem and, as such, should be installed in a manner which is reversible and does not damage the structure or materials during installation or removal.
- This procedure includes guidance on installing a netting bird deterrent system. This type of system is most commonly used to protect large areas of architectural detailing, especially carvings, sculpture and moldings. It is usually installed on the upper portions of a building, where its presence will not be as apparent.
- The netting system is designed to prevent birds from nesting in recessed portions of the building, in light wells, or under eaves by making entry into those areas difficult. Netting can be a desirable solution if hung correctly and if an inconspicuous color of netting is selected. It is most suited for large areas, is effective on most bird species, and can have a fairly long life span. This system, however, is time consuming and expensive to install and can obscure detailing. Furthermore, gaps and holes in the netting will render the system ineffective.
- See "General Project Guidelines" for general project guidelines to be reviewed along with this procedure. These guidelines cover the following sections:
- Safety Precautions
- Historic Structures Precautions
- Quality Assurance
- Delivery, Storage and Handling
- Project/Site Conditions
- Sequencing and Scheduling
- General Protection (Surface and Surrounding)
These guidelines should be reviewed prior to performing this procedure and should be followed, when applicable, along with recommendations from the Regional Historic Preservation Officer (RHPO).
- Samples: Submit a 12" x 12" sample of proposed bird netting to the RHPO for approval of color.
- Mock-ups: An area(s) selected by the RHPO will have a test installation of bird netting for approval by RHPO prior to beginning of work.
1.03 PROJECT/SITE CONDITIONS
- Do not use adhesive on wet or damp surfaces or when temperatures are above 120 degrees F or below 45 degrees F.
1.04 INSTALLER QUALIFICATIONS
A. Must be experienced at installing bird exclusion netting in comparable architectural applications evidenced by photographs showing successful installations of comparable complexity.
- Bird Busters
- Cascade Nets
- Bird Barrier
- Bird Netting: UV stable, knotted plastic netting in fabricated for architectural use in color to blend with masonry. Characteristics of netting including color and grade must be approved by RHPO.
- Anchors: Stainless steel mounting pins which will not rust or cause staining on masonry.
- Adhesive: Epoxy putty; high modulus, high strength, non-sag, two-component, epoxy resin adhesive, designed for vertical and overhead bonding, moisture insensitive, and in color approved by RHPO.
- Tensioning devices: Stainless steel or plastic hardware for retensioning netting after installation as required by location.
- Masonry drill
- Surface Preparation: Remove all bird excrement, from the application area. See 04510-02-R for guidance. Application must take place after masonry cleaning operations are completed, but may be scheduled for work while staging is in place.
3.02 ERECTION, INSTALLATION, APPLICATION
NOTE: OBTAIN APPROVAL FROM RHPO BEFORE PROCEEDING WITH THIS WORK.
- Follow manufacturer's printed instructions for netting installation. Area to be protected must be measured accurately.
- Mark on perimeter of area to be covered by netting where holes are to be drilled. Mount pins at mortar joints where possible.
- Using a 3/16" drill bit, drill holes approximately 8" apart, 1-1/2" deep and at a 45 degree angle . Remove all loose particles from the surface.
- Press epoxy putty into holes and set pins into putty.
- Reinforce edges of netting by using a simple weaving process with matching plastic thread.
- Stretch netting over area to be protected and attach to anchoring pins. Stretch netting so that the mesh runs vertically and horizontally, NOT diagonally. The netting will blend better with the background when stretched in a horizontal and vertical direction.