Why fifteen thousandths of a percentage point mattered

The size of the correction is trivial. Its consequence is not, and the minutes name why: “the timing of some rent increases due to the 90-day windows.”

Delaware's rent-increase machinery is a sequence of deadlines keyed to the certified figure. A community owner must give 90 days' notice. Where the increase exceeds the ceiling, a meeting is triggered; residents or a homeowners association may then petition the Authority for arbitration within 30 days; and an appeal to the Superior Court runs 30 days from the arbitrator's decision.

A certification issued against the wrong index is a defective starting point for that whole chain. An increase certified as within the ceiling might sit above the corrected one — which changes whether a meeting was required at all, and therefore whether the residents' arbitration window ever opened. That is why the fix was corrected certifications rather than a corrected number on a webpage.

Who found it, and what that tells you

The error was caught by an attorney for a community owner — not by the agency, not by a resident, and not by any advocacy group.

That asymmetry is the honest picture of who is checking Delaware's rent machinery. Community owners are repeat players with counsel who track the index because their revenue depends on it. Residents encounter the system once, under a 90-day clock, usually without a lawyer.

Legal help does exist and is state-funded: the Manufactured Home Owner Attorney Fund pays Community Legal Aid Society to represent Delaware homeowners, and it worked 211 cases in the fiscal year to June 30, 2025. But the fund's statutory rent-arbitration role is narrow: § 7046(b)(8) covers challenging an increase only where the proposed increase is 3% or more above the CPI-U, and only where requested by a homeowners association representing at least 25% of homeowners or by a simple majority of noticed homeowners.

The regulation that no longer matches the statute

Here is the finding that should concern anyone relying on Delaware's published rules rather than its statute.

The Authority's own arbitration regulation — 1 DE Admin. Code 202, Rent Increase Dispute Resolution Procedures — still defines CPI-U as “the average annual increase of the Consumer Price Index For All Urban Customers in the Philadelphia-Wilmington-Atlantic City area for the most recently available preceding thirty-six (36) month period.”⁴

The controlling statute uses a 24-month CPI-U calculated by DSHA. The regulation cites §§ 7012, 7026, 7040, 7042, 7043 and 7044 and contains no reference at all to §§ 7051A, 7052A or 7052B — which is to say, none to the entire current rent-increase framework.

Its last amendment was 18 DE Reg. 637, February 1, 2015. The companion trust-fund regulation, 1 DE Admin. Code 201, was last amended in April 2014. Nothing was proposed for either in 2025 or 2026.

The statute governs, so this is not a live legal ambiguity so much as a trap: a resident or manager who reads the regulation gets a 36-month Philadelphia-area figure and a set of section references that no longer describe the law.

What this framework does not do

It is worth stating plainly. Delaware does not cap lot rent. The ceiling determines only whether an increase needs justifying. Above it, the owner must justify; the increase is not forbidden.

Two recent developments bound the justification question. The Delaware Supreme Court held in July 2025 that only the direct costs of a capital improvement can justify an above-CPI-U increase — not return on investment, depreciation, or the owner's income tax on the higher rent. And SB 235, signed July 23, 2026, made the §§ 7052A/7052B calculations permanent by deleting their July 1, 2027 sunset — while providing that they replace the § 7052 grounds the Supreme Court construed. How those two fit together is unresolved.

Note also what § 7052B permits: an increase where allowed expenses, including taxes, rise faster than the county's 24-month CPI-U. Two 2025 floor amendments that would have barred passing the New Castle County school-tax reset through to lot rent were stricken.

What to watch next

The index resets whenever new CPI-U data lands, so the ceiling above will change. Check DEMHRA's published figure against the date of your notice, not against the figure you last saw.

Two things worth monitoring: whether DSHA's calculation method is documented anywhere public — we could not find it — and whether Regulation 202 is ever updated. Eleven years is a long time for a regulation to contradict its own statute.