A landlord has been granted leave to appeal to the Supreme Court in a case that could have significant implications for thousands of ongoing possession proceedings and rental compliance requirements in Wales.
The Harker v Hubert case centres on whether a Section 21 notice served in 2023 can be invalidated due to the absence of a Gas Safety Certificate when the tenancy began in 2007, before such certificates became a legal requirement for valid Section 21 notices.
Background to the dispute
The tenants argue that their Section 21 notice is invalid because no Gas Safety Certificate could be found from 2007 when their tenancy commenced. Although the certificate requirement was not linked to Section 21 evictions until the Deregulation Act 2015, the tenants contend that notices served after the law changed remain invalid if the initial certificate was never provided.
Changes introduced by the Deregulation Act 2015 imposed two key obligations on landlords: providing a Gas Safety Certificate within 28 days of any previous certificate expiring, and providing one before a tenant first occupies the property.
A County Court rejected the tenants’ claim in 2025, but the Appeal Court subsequently ruled in their favour. The landlord has now secured permission to take the case to the Supreme Court for a final determination.
Industry implications
David Smith, a property law specialist at Bishop & Sewell, noted that despite Section 21 evictions being abolished under the Renters’ Rights Act in England, the case remains relevant. “There are several thousand Section 21 possession cases being heard in the county courts right now and Wales has and will continue to have a very similar restriction on Gas Safety Certificates for its Section 21 equivalent,” he said.
The case highlights ongoing confusion around compliance requirements that have affected the rental sector’s operational standards. Smith explained that the second requirement to provide a certificate before occupation “was widely flouted as it had become conflated with the first so that many landlords and agents thought, wrongly, that provision of a GSC within 28 days of the tenancy start was sufficient.”
Previous case law
In the Trecarrell House v Rouncefield case, the Court of Appeal provided some relief by ruling that landlords who obtained a Gas Safety Certificate before a tenant moved in but failed to provide it would still be compliant. However, the judgment left unresolved what happens when a landlord never obtained a certificate or cannot demonstrate they did so.
This unresolved question forms the core of the Harker v Hubert dispute now heading to the Supreme Court.
Conclusion
The Supreme Court’s decision will provide clarity on whether historic compliance failures can invalidate possession notices served years later under different legal frameworks. The ruling could affect thousands of current possession cases and establish precedent for rental sector regulations in Wales, where Section 21-equivalent provisions remain in force. Landlords and letting agents await the judgment to understand their obligations regarding documentation from tenancies that predate current legislative requirements.
