Rhode Island Building Code — Design Architect Knowledge Base

Adopted Codes

| Code | Edition | RI Adoption | |------|---------|-------------| | IBC (International Building Code) | 2021 | With SBC amendments | | IRC (International Residential Code) | 2021 | With SBC amendments | | IECC (International Energy Conservation Code) | 2021 | With SBC amendments | | ASCE 7 (Structural Loads) | 7-16 | Referenced by IBC | | AISC 360 (Steel Construction) | Current | Referenced by IBC | | NDS (National Design Specification — Wood) | Current | Referenced by IRC | | ACI 318 (Concrete) | Current | Referenced by IBC |

SBC Amendments (State Building Commission)

| Amendment | Subject | |-----------|---------| | SBC-1 | Administrative provisions | | SBC-2 | Radon mitigation required (sub-slab rough-in all new residential) | | SBC-3 | Lead paint — RI Lead Hazard Mitigation Act (§23-24.6) | | SBC-4 | Energy code modifications | | SBC-5 | Accessibility | | SBC-6 | Fire protection | | SBC-7 | Structural (frost depth, snow loads) | | SBC-8 | Plumbing (no AAVs — hard vent through roof required) |

IBC vs IRC Decision Tree

When IRC Applies (Prescriptive Path)

• Detached one/two-family dwellings

• Townhouses (≤ 3 stories)

• Conventional wood frame or ICF construction

• ≤ 3 stories above grade

When IBC Applies (Engineered Path)

• ANY steel primary structural frame ← ML Systems triggers this

• Non-conventional structural systems

• Mixed occupancy

• > 3 stories

ML Systems Consequence

ML Steel hybrid = IBC path, which requires:

• Engineered design by PE (not prescriptive tables)

• Chapter 17 special inspections for steel

• Formal load calculations (not span table lookups)

• Construction type classification (typically Type VB — non-rated, or Type IIIB)

Special Inspections (IBC Chapter 17)

Required for ML Steel

| Inspection | What's Checked | When | |-----------|----------------|------| | Material verification | Steel grade matches mill cert (HSLA 60–80 ksi) | Delivery | | Bolt installation | A325/A490 torque verification, snug-tight or turn-of-nut | During erection | | Connection assembly | End plate alignment, bolt pattern, washer placement | During erection | | Welding (if any) | Should be ZERO for DfD — flag if field welding occurs | Continuous | | Column plumb | Tolerance per AISC Code of Standard Practice | After erection | | Base plate/anchor bolt | Alignment with foundation survey, grouting | Before erection |

Inspector Qualifications

• Must be independent of contractor

• ICC certification or PE with structural experience

• Reports directly to building official

RI-Specific Requirements

Frost Depth

• 40 inches for all of RI except Block Island (30")

• All footings must extend below frost depth

• Practical: design to 42"–48" for safety margin

Radon

• Required: Sub-slab depressurization system rough-in in all new residential

• PVC pipe from sub-slab aggregate through conditioned space to roof

• Fan location designated (attic or exterior)

• Even if radon test comes back low — rough-in is mandatory

Lead Paint (§23-24.6)

• RI has the strongest lead laws in the US

• ANY work disturbing paint in pre-1978 buildings requires lead-safe practices

• Certified renovator required (EPA RRP rule + RI enhanced)

• Dust wipe clearance testing after work

• Spec section triggered: 02 83 00 Lead Abatement

Asbestos

• Pre-1980 buildings: assume asbestos in floor tile (9×9"), pipe wrap, vermiculite insulation

• Testing required before demolition/renovation

• Licensed asbestos abatement contractor if ACM confirmed

• RIDEM notification required for abatement > 3 LF pipe or 3 SF surfacing

• Spec section triggered: 02 82 00 Asbestos Abatement

Plumbing — No AAVs

• RI does NOT permit Air Admittance Valves (AAVs)

• All drain/waste/vent stacks must vent through the roof

• Hard vent only — no cheater valves, no studor vents

• Impacts wet wall design: must route vent pipe vertically through roof

CRMC (Coastal Resources Management Council)

• Mandatory review for properties within 200' of coastal features

• CRMC assent required before building permit

• Affects: foundation type, flood elevation, setbacks from coastal bank

• Can add 30–60 days to permitting timeline

DEM (Department of Environmental Management)

• Wetland buffers: 50' perimeter, 100' riverbank

• Freshwater wetland alteration permit if building within buffer

• Stormwater management for sites > 1 acre disturbance

• Individual septic system approval (if not municipal sewer)

Permits Required

| Permit | Issuing Authority | Timeline | |--------|-------------------|----------| | Building permit | Municipal building official | 14–30 days | | Demolition permit | Municipal building official | 7–14 days | | Electrical permit | Municipal / state | With building permit | | Plumbing permit | Municipal / state | With building permit | | CRMC assent (if coastal) | CRMC | 30–60 days | | DEM wetlands (if applicable) | RIDEM | 30–90 days | | Lead-safe work permit (pre-1978) | RI DOH | 7 days | | Zoning variance (if needed) | Municipal zoning board | 4–8 weeks |

RI Inspection Sequence (Typical New Construction)

| # | Inspection | What's Checked | |---|-----------|----------------| | 1 | Footing | Depth below frost (40"), rebar, soil bearing, form dimensions | | 2 | Foundation | Walls/grade beams before backfill, waterproofing, anchor bolts | | 3 | Slab | Vapor barrier, rebar/WWF, radon rough-in, sub-grade prep | | 4 | Steel erection | Special inspection per IBC Ch 17 (see above) | | 5 | Rough framing | Studs, trusses, sheathing, nailing patterns, connectors | | 6 | Rough MEP | Plumbing pressure test, vent routing, electrical circuits, HVAC | | 7 | Insulation | Before GWB — R-values match spec, air sealing at penetrations | | 8 | GWB (fire-rated only) | Type X at garage separation, around steel | | 9 | Final building | Life safety, egress, smoke/CO detectors, accessibility | | 10 | Final MEP | Fixtures operational, GFCI/AFCI, blower door test | | 11 | Certificate of Occupancy | All inspections passed, all conditions met |

Energy Code — IECC 2021 Climate Zone 5A

Prescriptive Path (Table R402.1.2)

| Component | R-Value | U-Factor | |-----------|---------|----------| | Ceiling | R-49 | 0.026 | | Wood frame wall | R-20 + R-5ci or R-13 + R-10ci | 0.060 | | Steel frame wall | R-13 + R-10ci | 0.064 | | Floor over unconditioned | R-30 | 0.033 | | Basement wall | R-15/R-19 or R-10ci | — | | Slab perimeter | R-10, 4' depth | — | | Windows | — | 0.30 | | Skylights | — | 0.55 | | SHGC (all orientations) | — | 0.40 |

ML Systems Wall Assembly vs Code

| Assembly | R-Value | U-Factor | Meets Code? | |----------|---------|----------|-------------| | 2×6 + R-21 batt + R-5 ci | R-26 | 0.038 | EXCEEDS (steel path: R-13 + R-10ci = U-0.064) | | 2×6 + R-21 batt + R-10 ci | R-31 | 0.032 | EXCEEDS significantly |

Air Sealing Requirements

• Blower door test: ≤ 5 ACH50 (residential) — ML Systems targets ≤ 3 ACH50

• Visual inspection of air barrier at all penetrations

• Caulk/foam at all framing-to-sheathing joints, window/door rough openings, utility penetrations

• Taped sheathing seams = primary air barrier plane

Duct Leakage

• ≤ 4 CFM25 per 100 SF of conditioned floor area (ducts in conditioned space)

• ≤ 8 CFM25 per 100 SF (ducts outside conditioned space)

• Mini-split systems: no ductwork = automatic compliance (ML Systems advantage)