IPMC § 302.5: Rodent Harborage. Property exterior must be kept free from rodent harborage or infestation. If rodents are found, they should be eliminated using an approved method in a manner that is not injurious to human health. After extermination, measures should be taken to prevent reinfestation. (Ideally, the code would require or promote integrated pest management.)

IPMC § 303.5: Foundation Walls. Foundation walls must be maintained free from open cracks to prevent the entry of rodents and other pests.

IPMC § 303.13.1: Glazing. Glazing materials must be free from cracks and holes. (Holes in glass can admit moisture and pests.)

IPMC § 303.14: Window Screens. During [time period to be determined by code officials], doors, windows, and other outside openings required for ventilation must have tightly fitting screens of at least 16 mesh per inch. (Screens help to prevent pests from entering the home.)

IPMC § 303.16: Basement Hatchways. Basement hatchways must be maintained to prevent the entry of rodents, rain, and surface drainage water.

IPMC § 303.17: Guards for Basement Windows. Openable basement windows should have rodent shields, storm windows, or other barriers against the entry of rodents.

IPMC § 306.1: Infestation. Structures should be kept free of insect and rodent infestation. When insects or rodents are found, they should be exterminated using a process not injurious to human health. After extermination, measures should be taken to prevent reinfestation. (Ideally, the Code would require or promote integrated pest management.)

IRC § 408.2: Openings for Under-Floor Ventilation. Ventilation openings must be covered with material such as perforated sheet metal plates, cast iron grills, wire mesh, or other materials. (Installing a covering material keeps rodents or other animals from entering the crawl space.)

IRC § 408.4: Under-Floor Space/Removal of Debris. The under-floor grade must be cleared of all vegetation, organic material, and construction materials. (These materials can attract termites, insects, or other animals.)

IRC § 504.2: Pressure Treated Wood Floors (On Ground)/Site Preparation. The area within the foundation walls must have all vegetation and foreign material removed.

IRC § 506.2: Concrete Floors (On Ground)/Site Preparation. The area within the foundation walls must have all vegetation, top soil, and foreign materials removed.

IBC § 1202.2.1. Openings into Attic. Exterior openings into the attic space must be covered with corrosion-resistant wire cloth screening, perforated vinyl, or other similar material that will prevent the entry of birds, squirrels, rodents, and other similar animals into the building.

IBC § 1202.3. Openings for Under-Floor Ventilation. Ventilation openings must be covered with perforated plates, corrosion-resistant wire mesh, or other covering to keep small animals out.

IBC § 2304.11.6: Termite Protection. In geographical areas where the hazard of termite damage is great, floor framing must be of naturally durable or preservative-treated wood, or provided with approved methods of termite protection. (Some preventative termite treatments are highly toxic and should not be used.)

IBC Appendix F: Rodent Proofing. Provides minimum mechanical methods for preventing the entry of rodents into buildings, including covering foundation wall vents with metal grills or plates; sealing openings in foundation and exterior walls created for pipes, cables, and conduits; covering windows located within two feet of ground level with wire screens; and ensuring minimum clearance between doors and door jambs.

IECC § 502.2: Heating and Cooling Criteria/Table (footnote d). Slab edge insulation is not required for unheated slabs in areas of very heavy termite infestation probability. (This insulation can provide a pathway for termites.)

IECC § 602.1.10: Caulking, Sealants, and Gasketing. All joints, seams, penetrations, openings, and other sources of air leakage through the building envelope must be caulked, gasketed, weatherstripped, wrapped, or otherwise sealed to prevent uncontrolled air movement. (This helps to prevent the entry of pests and moisture into the building.)

IMC § 401.6: Outdoor Opening Protection. Air exhaust and intake openings terminating outdoors must be protected with corrosion-resistant screens or grills, and protected against weather conditions. (This protects against entry of pests and moisture.)

IMC § 504.4: Clothes Dryer Exhaust/Exhaust Installation. Dryer exhaust ducts must terminate outside the building, and be equipped with backdraft dampers, not screens. (The damper will prevent the entry of rodents. Screens are not permitted, because they could become clogged with lint.)

About the Codes

• The IPMC applies to existing residential and commercial structures and premises.

• The IRC regulates the construction, alteration, repair, use, and occupancy of detached one- and two-family dwellings and townhouses not more than three stories high. While the section numbers in the code are preceded by a letter, e.g., “R” for the administrative, definitions, and building, planning, and construction portions of the code, “N” for the energy conservation portion, etc., those prefixes have been omitted from this document.

• The IBC governs new construction in residential buildings 4 or more stories high.

• The IECC sets forth alternative compliance approaches for new construction in both residential (one-and two-family buildings, and multi-family buildings three or less stories in height) and commercial buildings (including residential buildings four or more stories high). For residential buildings, these approaches include a systems approach, which considers the entire building and its energy-using systems as a whole; an approach based on the performance of components in the building envelope; an approach based upon the performance of the building envelope as a whole; and others. Commercial buildings can comply using a prescriptive approach, which sets standards for the building envelope, mechanical, lighting, and service water-heating subsystems; a total building performance approach; or an energy cost budget approach. Therefore, the code provisions cited in this table may not be required in a particular building if that building is constructed using an alternative approach to compliance.

• The IMC governs the design, installation, maintenance, alteration, and inspection of permanently installed mechanical systems used to control environmental conditions within buildings. The IMC does not require the removal and replacement of existing mechanical systems, although work performed on existing systems must conform to the code’s requirements for new work.