CHAPTER 4-03
2018 INTERNATIONAL RESIDENTIAL CODE

Sections:

4-03-001-0001    AMENDMENTS, ADDITIONS, AND DELETIONS

4-03-001-0001 AMENDMENTS, ADDITIONS, AND DELETIONS

The following provisions shall have the effect of either amending, adding to, or deleting from the 2018 International Residential Code adopted in Flagstaff City Code, Title 4, Building Regulations, Chapter 4-01, Administrative Enactments, Section 4-01-001-0002, Adoption of Model Codes.

CHAPTER 1, SCOPE AND ADMINISTRATION

Section R102, Applicability

Amend 2018 IRC R102.5, Appendices, by adding:

The following Appendices are hereby adopted as part of the IRC: APPENDIX F - Radon Control Methods

APPENDIX H - Patio Covers

APPENDIX J - Existing Buildings and Structures

APPENDIX M - Home Day Care, R-3 Occupancy

APPENDIX Q - Tiny houses

APPENDIX R - Light straw clay construction

APPENDIX S - Strawbale construction

APPENDIX T - Solar-ready provisions - detached one- and two-family dwellings and townhouses

Section R103, Department of Building Safety

Amend 2018 IRC R103.1, Creation of enforcement agency, by deleting and replacing with:

The Building Safety Program of the Planning & Development Services Section, Community Development Division is appointed as the regulating office and the official in charge thereof shall be known as the Building Official.

Section R104, Duties and Powers of the Building Official

Amend 2018 IRC R104.7, Department records, by deleting and replacing with:

The Building Official shall keep comprehensive records of applications, permits issued, certificates issued, inspections made, reports rendered, and of notices of orders issued. All such records shall be open to public inspection at the stated office hours but shall not be removed from the office of the Building Official. All records are kept in both hard copy and electronic format. The electronic format information may be requested on a "walk-in" basis and reviewed during normal working hours. Copies or inspection of original documentation requires written notice and reasonable amount of time for Staff to collect the required records from an off-site warehouse location. Written requests will go through the City Clerk’s office for processing.

Section Rl05, Permits

Amend 2018 IRC Rl05.1, Required, by adding:

All manufactured housing (housing classified as modular, factory built or manufactured house) installed within the City of Flagstaff will be designed to meet Arizona Department of Housing, Office of Manufactured Housing standards. The City of Flagstaff enforces a 60 pound per square foot ground snow load for site-built construction. Arizona Department of Housing standards for snow winter areas in Arizona is not consistent with local conditions and owners should be aware of the differences.

For "used" manufactured housing or "resale"/relocated manufactured housing being brought into the City of Flagstaff, the following applies: As per direction from the Arizona Department of Housing, Office of Manufactured Housing, Arizona Revised Statutes Title 41, requires that all manufactured housing units be certified to meet the minimum standards of the United States Department of Housing and Urban Development and are to be designed in accordance with consistent Arizona Department of Housing standards for manufactured homes and related industries. An applicant requesting an installation permit and inspection will be required to provide proof to the Building Official of the current State certification or re-certification of the unit.

Amend 2018 IRC R105.2, Work exempt from permit, as follows:

Add the following to Building Item #1: Accessory structures with floor area less than 200 square feet require a Minor Improvement Permit per Flagstaff City Code, Title 10, Flagstaff Zoning Code.

Revise Building Item #2 as follows: Fences and walls not over six (6) feet high. Fences and walls 6 feet and under require a Minor Improvement Permit per Flagstaff City Code, Title 10, Flagstaff Zoning Code.

Add the following to Building Item #10: These decks require a Minor Improvement Permit per Flagstaff City Code, Title 10, Flagstaff Zoning Code.

Amend 2018 IRC R105.5, Expiration, by deleting and replacing with:

Every Residential Building Permit issued shall become invalid unless the work authorized by such permit is completed within 365 days from the issuance date of the building permit. The Building Official is authorized to grant, when request for extension is received in writing, one extension not to exceed 180 days. The extension shall demonstrate cause such as financial, weather delays, material delivery, etc. The permit may be extended for an additional 365 days by paying one half the original permit fee (not including the plan review fee), thereby allowing a maximum time of completing the project to 910 days. Failure to obtain a Certificate of Occupancy within 910 days shall result in a report being recorded with the Coconino County Recorder’s Office for incomplete work or no final inspection report of the project.

All residential Over-the-Counter Permits for plumbing, mechanical, electrical, and re-roofing shall be valid for a maximum period of 180 days.

Section R106, Construction Documents

Amend 2018 IRC R106.1, Submittal documents, by adding:

Residential, single family detached, structures are exempt from the requirements for a Registered Design Professional under Arizona Revised Statutes unless circumstances dictate the necessity for professional design submittal. Duplexes and triplex units which do not exceed 3,000 square feet, two stories or a total occupant load of twenty (20), may also be designed by a non-registrant as long as the units have only one owner.

Sub-assemblies, such as commercially manufactured roof trusses or floor beams that indicate all imposed loading may be submitted without the seal of an Arizona Registered Design Professional. If a Registered Design Professional has sealed the construction documents, the Registered Design Professional shall state they have reviewed and approved of the design either on the construction documents or by providing a written letter stating as such, signed, sealed, and dated.

Any retaining walls having any imposed surcharges from adjacent structural elements or unbalanced loading that exceed four (4) feet, shall be designed by an Arizona Registered Design Professional and shall be submitted at the time of permit application.

Amend 2018 IRC R106.1, Submittal documents, by adding subsection R106.1.S, Model plans:

Rl06.l.5 Model plans. An applicant may submit a model plan, which is a residential construction plan used two or more times. If approved, only modifications not shown on the model plan must be submitted for review. All modifications shall be clearly identified by clouded symbols, deltas, or other appropriate means. The review fee for modifications only will be hourly in accordance with city fee schedule. If, in Building Official’s judgement, the modifications are excessive or inadequately defined, the full plan review fee will be charged.

Section R108, Fees

Amend 2018 IRC R108.2, Schedule of permit fees, by adding:

The current schedule of permit fees is on file in the Office of Building Safety and available on the City of Flagstaff website (www.flagstaff.az.gov).

Amend 2018 IRC 108.4, Related fees, by adding:

Re-inspection fees may be assessed for each inspection or re-inspection when the portion of work for which the inspection was scheduled is not complete or when corrections from a previous inspection are not made. Other events which may require the imposition of a re-inspection fee are:

1.    Failure to have the inspection record on the job site when the inspector arrives    ·

2.    The approved plans not on the job site for the inspector to review

3.    Failure to provide access to the job site or area to be reviewed by the inspector.

Appeals for such fees are made to the Building Official. To obtain a reinspection after the inspector has left notice that a fee shall be assessed, the applicant shall pay a $94.00 fee to the Community Development counter.

Amend 2018 IRC R108.5, Refunds, by adding:

The applicant may receive up to 80% refund for the building permit fee (not including plan review fee) if no work has begun and no inspections have been performed. No refund of the plan review fee is authorized.

The Building Official shall determine, based upon work completed, the portion of fees paid to be refunded. There shall be no refund of any required deposit once the administrative routing and plan review process has begun.

Amend 2018 IRC R108.6, Work commencing before permit issuance, by adding:

Any person who commences any work on a building, structure, electrical, gas, mechanical, or plumbing system before obtaining the necessary permits shall be subject to an investigation fee of $94.00 or twice the permit fee, whichever is greater.

Section R110, Certificate of Occupancy

Amend 2018 IRC Rl10.4, Temporary occupancy, by adding:

Temporary Certificate of Occupancies for residential construction (detached single family dwellings and duplexes) is not authorized.

Exceptions:

1.    When a driveway approach cannot be poured due to weather, the Building Official can approve a Temporary Certificate of Occupancy after the applicant has posted a bond with the City of Flagstaff.

2.    If the structure meets all the requirements for habitable space and sanitation, then a Temporary Certificate of Occupancy will be granted. Any unfinished items (i.e. bonus rooms, basement finishing, etc.) will be annotated in the inspection record as "not inspected" at the time of Temporary Certificate of Occupancy issuance. Applicants moving into a dwelling prior to receiving a Certificate of Occupancy may be evicted as the property is posted "NO OCCUPANCY" by the building inspector or Building Official.

Section R112, Board of Appeals

Amend 2018 IRC 112.1, General, by deleting and replacing with:

In order to hear and decide appeals of orders, decisions or determinations made by the Building Official relative to the application and interpretation of this code, there shall be and is hereby created a Building and Fire Code Board of Appeals per Flagstaff City Code, Title 2, Boards and Commissions.

CHAPTER 2, DEFINITIONS

Section R202, Definitions

Amend 2018 IRC Section R202 by adding:

ACCESSORY DWELLING UNIT. Accessory dwelling units (ADU) are defined by the Flagstaff City Code, Title 10 - Flagstaff Zoning Code.

ACCESSORY ENERGY SYSTEM. An accessory energy system will include wind turbines, PV solar, thermal solar, geo-thermal, bio-mass and other technologies that provide heating, cooling or electrical energy. The systems will be subject to a· building permit and limited by zoning ordinances for visual, design, height and setback requirements.

CHAPTER 3, BUILDING PLANNING

Section R301, Design Criteria

Amend 2018 IRC Table R301.2(1), Climatic and Geographic Design Criteria, as follows:

Ground snow load: 60 psf

Wind design - Speed (mph): 115

Wind design - Topographic Effects: NO

Wind design - Special wind region: NO

Wind design - Windborne debris zone: NO

Seismic design category: C

Subject to damage from - Weathering: Moderate

Subject to damage from - Frost line depth: 30 inches

Subject to damage from - Termite: Moderate to heavy

Winter design temperature: 4 degrees F

Ice barrier underlayment required: YES

Flood hazards: a)12-16-1975, b)0l-19-1983, c)09-03-2010*

Air freezing index: 1013

Mean annual temperature: 45.4 degrees F

Residential heating and cooling equipment sizing using Manual J is optional per 2018 IRC M1401.3. When opting to use ACCA Manual J for HVAC system design, the criteria shall be from ACCA Manual J, Table 1A for Arizona, Flagstaff AP.

*The flood hazard dates reflect the current National Flood Insurance Program and the date of the currently effective "FIRM" Map (used by the City of Flagstaff). These maps are updated by the issuing agency and adopted by Storm Water Management without notice.

Amend 2018 IRC Table R301.5, Minimum Uniformly Distributed Live Loads, by revising the following values:

Habitable attics and attics served with fixed stairs: 40 psf

Sleeping rooms: 40 psf

Section R302, Fire-Resistant Construction

Amend 2018 IRC R302.13, Fire protection of floors, by adding the following to Exceptions:

5. Floor assemblies located directly over crawl spaces with fuel-fired or electric-powered heating appliances where the maximum distance from crawl space floor to finish floor above does not exceed four (4) feet at any point.

Section R303, Light, Ventilation and Heating

Amend 2018 IRC R303.4, Mechanical ventilation, by deleting and replacing with:

Where the air infiltration rate of a dwelling unit is 5 air changes per hour or less where tested with a blower door at a pressure of O.2 inch wg (50 Pa) in accordance with Section N1102.4.1.2, the dwelling unit may be provided with whole-house mechanical ventilation in accordance with Section M1505.4.

Section R309, Garages and Carports

Amend 2018 IRC R309.5, Fire sprinklers, by deleting in its entirety.

Section R313, Automatic Fire Sprinkler Systems

Amend 2018 IRC R313.2, One- and two-family dwellings automatic fire sprinkler systems, by deleting and replacing with:

An automatic residential fire sprinkler system may be installed in one- and two-family dwellings. Arizona Revised Statutes prohibits jurisdictions from adopting any ordinance that mandates fire sprinklers in newly constructed one- and two-family dwellings.

CHAPTER 4, FOUNDATIONS

Section R410, General

Amend 2018 IRC R401.4.1, Geotechnical evaluation, by deleting and replacing with:

Construction in all new residential subdivisions require a geotechnical evaluation with foundation recommendations. In established areas of the City of Flagstaff, "in-fill" lots or vacant lots in subdivisions established prior to 1996, the designer may use a load-bearing pressure of 1500 pounds per square foot in lieu of a geotechnical evaluation. Upon site excavation of foundation, where the Building Official determines that in-place soils with an allowable bearing capacity of less than 1500 pounds per square foot (psf) are likely to be present at the site, then allowable bearing capacity shall be determined by a geotechnical evaluation at the expense of the permit applicant.

Section R403, Footings

Amend 2018 IRC R403.1, General, by adding:

All footings located less than eighteen (18) inches below existing grade to be air entrained, 3,500 psi concrete (severe weather), and pinned to rock at intervals specified for foundation wall vertical reinforcements or as specified by the Arizona Registered Design Professional of Record.

CHAPTER 5, FLOORS

Section R502, Wood Floor Framing

Amend 2018 IRC R502.3, Allowable joist spans, by adding:

The Western Lumber Span Tables for Floor and Ceiling Joists and Roof Rafters is adopted as a secondary reference to Tables R502.3.l(l) and R502.3.1(2).

Amend 2018 IRC R502.3.1, Sleeping areas and attic joists, by deleting and replacing with:

Table R502.3.l(l) shall be used to determine the maximum allowable span of floor joists that support sleeping areas and attics that are accessed by means of fixed stairway in accordance with Section R311.7 provided that the design live load does not exceed 40 pounds per square foot (1.44 kPa) and the design dead load does not exceed 20 pounds per square foot (0.96 kPa). The allowable span of ceiling joists that support attics used for limited storage or no storage shall be determined in accordance with Section R802.5.

Section R507, Exterior Decks

Amend 2018 IRC R507.5, Deck beams, by adding:

The Western Lumber Span Tables for Floor and Ceiling Joists and Roof Rafters is adopted as a secondary reference to Tables R507.5.

Amend 2018 IRC R507.6, Deck joists, by adding:

The Western Lumber Span Tables for Floor and Ceiling Joists and Roof Rafters is adopted as a secondary reference to Tables R507.6.

Amend 2018 IRC R507.9.2, Lateral connection, by adding:

Exception: Attached first floor decks that do not exceed 30 inches above grade at any point.

CHAPTER 7, WALL COVERING

Section R702, Interior Covering

Amend 2018 IRC R702.7, Vapor retarders, by deleting the following:

Class I or II vapor retarders are required on the interior side of frame walls in Climate Zones 5, 6, 7, 8, and Marine 4.

CHAPTER 8, ROOF-CEILING CONSTRUCTION

Section R802, Wood Roof Framing

Amend 2018 IRC R802.4.1, Rafter size, by adding:

The Western Lumber Span Tables for Floor and Ceiling Joists and Roof Rafters is adopted as a secondary reference to Tables R802.4.l(l) through R802.4.1(8).

CHAPTER 9, ROOF ASSEMBLIES

Section R904, Materials

Amend 2018 IRC R904.3, Material specifications and physical characteristics, by adding:

All roofing materials used shall be Class "A" or "B" and rolled roofing shall be a Class A or B material and shall be a· self-adhering, polymer modified bitumen material.

Section R905, Requirements for Roof Coverings

Amend 2018 IRC R905.7, Wood shingles, by deleting in its entirety.

Amend 2018 IRC R905.8, Wood shakes, by deleting in its entirety.

CHAPTER 11, ENERGY EFFICIENCY

Section N1102, Building Thermal Envelope

Amend 2018 IRC N1102.1.2, Insulation and fenestration criteria, by revising/adding the following to Table N1102.1.2 as follows:

Climate Zone 5, Wood frame wall R-value, shall be 15 high density in existing 2x4 framed walls in remodel work only.

Footnote b, add Exception: Windows used for the installation of glazing for an approved passive solar design.

Amend 2018 IRC N1102.2, Equipment sizing and efficiency rating (Mandatory), by adding:

Furnaces installed in new construction shall be 90% condensing type furnaces. Exception: For replacement furnaces, installation of a 90% condensing type furnace is voluntary.

CHAPTER 20, BOILERS AND WATER HEATERS

Section M2005, Water Heaters

Amend 2018 IRC M2005.1, General, by adding:

Water heaters shall be capable of being removed without first removing a permanent portion of the building structure or any other appliance.

CHAPTER 24, FUEL GAS

Section G2445, Unvented Room Heaters

Amend 2018 IRC Section G2445, Unvented Room Heaters, by deleting in its entirety.

CHAPTER 26, GENERAL PLUMBING REQUIREMENTS

Section P2602, Individual Water Supply and Sewage Disposal

Amend 2018 IRC P2602.1, General, by adding:·

Building sanitary drainage piping and systems that connect to private sewage disposal systems shall be approved by Coconino County Environmental Quality prior to installation.

SECTION P2603, STRUCTURAL AND PIPING PROTECTION

Amend 2018 IRC P2603.5.1, Sewer depth, by deleting and replacing with:

Building sewers that connect to private sewage disposal systems shall be approved by Coconino County Environmental Quality. Building sewers that connect to the City of Flagstaff’s sewage disposal system shall be not less than twelve (12) inches below grade.

CHAPTER 29, WATER SUPPLY AND DISTRIBUTION

Section P2903, Water Supply System

Amend 2018 IRC Table P2903.2, Maximum Flow Rates and Consumption for Plumbing Fixtures and Fixture Fittings, by revising and adding as follows:

Maximum Flow Rate or Quantity for a Water Closet to 1.3 gallons.

Dual-flush water closets: The effective flush volume shall not exceed 1.28 gallons (4.8 liters). The effective flush volume is the average flush volume of two reduced flushes and one full flush. Flush volumes shall be tested in accordance with ASME A112.19.2/CSA B45.1 and ASME Al12.19.14.

CHAPTER 31, VENTS

Section P3103, Vent Terminals

Amend 2018 IRC P3103.1.1, Roof termination, as follows:

Replace "6" with "twelve (12)" and delete "or 6 inches (mm) above the anticipated snow accumulation, whichever is greater".

CHAPTER 39, POWER AND LIGHTING DISTRIBUTION

Section E3901, Receptacle Outlets

Amend 2018 IRC E3901.9, Basements, garages and accessory buildings, by adding:

At least one required garage receptacle shall be a 208/240-volt individual branch circuit for purposes of electric vehicle (EV) charging. The service panel or subpanel circuit directory shall provide a 50-ampere minimum dedicated branch circuit and a branch circuit overcurrent device. Electric vehicle supply equipment shall be installed in accordance with 2017 NFPA 70/NEC.

Exception: Additions and alterations to existing one- or two-family dwellings and townhouses constructed per the IRC are exempt from the EV charging requirement.

APPENDIX M, HOME DAY CARE - R-3 OCCUPANCY

Section Al0l, General

Amend 2018 IRC Appendix M, AM101.1, General, by adding:

AMl0l.1.1 A Home Occupation Permit issued by the City of Flagstaff is required prior to receiving any building permits for conversions or improvements.

APPENDIX T, SOLAR-READY PROVISIONS - DETACHED ONE- AND TWO-FAMILY DWELLINGS AND TOWNHOUSES

Section Tl0l, Scope

Amend 2018 IRC Appendix T, Tl0l.1, General, by deleting and replacing with:

These provisions shall be applicable for new construction.

Section T103, Solar-Ready Zone

Amend 2018 IRC Appendix T, T103.6, Capped roof penetration sleeve, by deleting in its entirety.

Amend 2018 IRC Appendix T, Tl03.8, Interconnection pathway, by deleting in its entirety.

Amend 2018 IRC Appendix T, T103.9, Electrical service reserved space, by deleting and replacing with:

When feasible, the main electrical service panel shall have a reserved space to allow installation of a dual pole circuit breaker for future solar electric installation and shall be labeled "for Future Solar Electric." The reserved space shall be positioned at the opposite (load} end from the input feeder location or main circuit location.

(Ord. 2019-16, Amended, 06/18/2019)