Issue 01 · Regulatory deep-dive · September 4, 2026

What Rule 2305 actually costs an Inland Empire warehouse tenant

South Coast AQMD Rule 2305 costs a 300,000 SF Inland Empire distribution tenant about $119,531 a year, or $0.40 per square foot. The WAIRE math, and the three lease terms to settle before you renew.

This week · Regulatory deep-dive
Rule 2305 · WAIRE

The air-quality rule that quietly adds a third of a dollar per foot to your occupancy cost

South Coast AQMD's warehouse indirect source rule is now in full effect across every size phase, and most tenants still treat it as a compliance chore rather than a rent line. It is a rent line. Here is the arithmetic, and where it lands in a lease negotiation.

Rule 2305 covers warehouses over 100,000 square feet, with the point-earning obligation attaching to operators using at least 50,000 square feet for warehousing activity. Every year the operator counts truck trips, converts them to weighted trips, and owes WAIRE points against that total:

WATTs = (Class 2b–7 trips) + 2.5 × (Class 8 trips)
WPCO  = WATTs × 0.0025 × annual variable

The 2.5 multiplier is the part that bites. A building served by tractor-trailers carries two and a half times the obligation of the same trip count in straight trucks — which describes essentially every big-box distribution tenant in the Inland Empire. Points are earned by acquiring zero- or near-emission trucks, installing chargers or hydrogen fueling, or drawing clean-truck visits. Operators who cannot or will not do any of that pay a mitigation fee of $1,000 per point, plus a 6.25% administrative fee.

One April 2026 update worth knowing: CARB-certified near-zero trucks meeting the 0.02 g/hp-hr standard now qualify on the WAIRE menu, which widens the compliance path for fleets not ready to go fully electric.

Where this shows up in a deal

Rule 2305 obligations follow the operator, not the owner. In a standard NNN lease that means the tenant, but the lease language often predates the rule and says nothing. Settle three points before signing: who holds the reporting obligation, who funds charging infrastructure if the building needs it, and whether mitigation fees are a recoverable operating expense. A tenant who negotiates charger installation into the TI package converts an annual fee into landlord capital.

Worked illustration

300,000 SF distribution building

Assumption, not a survey figure: 60 tractor-trailer trips per operating day, 300 operating days. Substitute your own gate counts.

Class 8 trips per year18,000
Weighted trips (× 2.5)45,000 WATTs
Points owed (× 0.0025)112.5
Mitigation fee at $1,000/pt$112,500
Administrative fee (6.25%)$7,031
Annual in-lieu cost$119,531
Per SF per year$0.40
Per SF per month$0.033
Share of IE West asking rent3.2%

Against the Q2 2026 IE West average of $1.038/SF NNN for 100,000 SF-plus space. Earning points instead of paying the fee is usually cheaper — that is the point of the rule — but the fee sets the ceiling on what compliance is worth.

Working through a renewal or a relocation?

I cover industrial sales, leasing and land across San Bernardino and Riverside Counties. Happy to run these numbers against your actual building and gate counts.

Email Ed

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