HVAC filter: MERV 13 or higher; whole-house ventilation per ASHRAE 62.2; balanced when possible

Description

Indoor airPLUS requires HVAC air filters with MERV 13 minimum rating (vs. standard MERV 8). Whole-house mechanical ventilation must comply with ASHRAE 62.2 with a flow rate verified by the HERS Rater. Balanced ventilation (HRV or ERV) is preferred — single-port supply only or exhaust only is allowed but loses energy. Ducts in conditioned spaces are preferred.

Why this exists

MERV 13 captures particulates including PM2.5 + COVID-sized particles (with the right filter face area). It demands HVAC equipment that can handle higher static pressure — architects should specify variable-speed blowers + size return ductwork to accept the filter pressure drop.

Categories

Source

Solver enforcement

Browsable only — the solver does not currently enforce this directive (no spec-level data to check against). This entry exists so the architect personas can cite it in conversation and the user can read what the rule says.

Related directives

• HVAC sizing per ACCA Manual J (loads), Manual S (equipment), Manual D (ducts); duct leakage ≤ 4-8 cfm/100 sqft · ENERGY STAR SFNH §HVAC Quality Installation — Manual J + Manual D + Manual S
• Whole-house mechanical ventilation per ASHRAE 62.2 (typically 7.5 cfm/person + 3 cfm/100 sqft, balanced when possible) · ENERGY STAR SFNH §Mechanical ventilation — ASHRAE 62.2 compliant
• Bulk water management: site drainage 6 in/10 ft away, capillary break above foundation, drainage plane behind cladding · Indoor airPLUS §Moisture Control — bulk water management
• Interior moisture: bath + kitchen exhaust to outdoors, no bath fans into attics, vapor retarder per climate zone · Indoor airPLUS §Moisture Control — interior moisture sources
• All fuel-fired appliances must be direct-vent / sealed-combustion / power-vent (no atmospheric-draft inside the envelope) · Indoor airPLUS §Combustion Pollutant Control — direct-vent OR no combustion inside