"A 20% reduction sounds positive, but if that change is driven by landlords leaving rather than properties improving, we are not solving the problem, we are reshaping it."
- Sián Hemming-Metcalfe - Inventory Base
The number of non-decent homes in England's private rented sector could fall by 20% over the next decade, but achieving even that modest target would cost the sector £1.43bn, according to new analysis from property inventory specialist Inventory Base.
The firm's review of government data shows that an average of 1.1 million private rented homes in England failed the Decent Homes Standard (DHS) each year between 2015 and 2024. Over that period, the sector made no meaningful progress.
The total number of non-decent homes fell by just 16.5% across the decade, and the 2024 figure of 1.1 million remains broadly unchanged from the pre-pandemic total recorded in 2019.
Why homes fail the standard
The primary reason properties fall below the DHS is failure to meet minimum requirements under the Housing Health and Safety Rating System (HHSRS), which accounts for 46.1% of all non-decent private rented homes. Thermal comfort failures account for a further 40.3%, disrepair for 25.8%, reflecting persistent maintenance backlogs, and shortfalls on modern facilities for 9.3%.
The fact that homes are identified and recorded as non-decent reflects some degree of intent to address a long-standing problem. The data, however, make clear that remediation efforts have had only a limited impact so far.
Regulatory pressure is building
From 2026, a combination of regulatory changes is beginning to reshape the landscape. The introduction of the Renters' Rights Act, ongoing reform of the HHSRS, and strengthened local authority enforcement are all expected to increase pressure on landlords to address non-compliance.
The economics of improvement, though, remain challenging.
Inventory Base's modelling suggests a 20% reduction in non-decent homes over ten years is a conservative but achievable target. Based on current data, this equates to removing 220,000 non-decent homes from the sector, or around 22,000 each year.
The projection assumes gradual, incremental change rather than any systemic transformation, reflecting behavioural shifts among landlords who either invest to meet compliance thresholds or exit a market where the financial consequences of non-compliance are growing. It also accounts for continued inconsistency in enforcement, given the resource constraints faced by local authorities.
The cost of modest progress
Even this measured level of improvement carries a substantial financial burden. At an average remediation cost of £6,500 per property, a conservative midpoint drawn from English Housing Survey data and government impact assessments, bringing 22,000 homes up to standard each year would require approximately £143m. Over a decade, that totals £1.43bn. Where Category 1 hazards are present, costs are likely to be higher still.
The private rented sector is still dominated by individual landlords with one or two properties, many of whom are already managing elevated mortgage rates and the phased removal of mortgage interest relief. For these landlords, a remediation bill of £6,500 to £10,000 may make exiting the sector a more financially rational decision than investing to achieve compliance.
Attrition, not improvement
That dynamic introduces a significant complication. A notable proportion of any projected reduction in non-decent homes may be driven by landlord attrition rather than genuine improvements in housing quality.
Where that happens, properties do not improve; they simply leave the private rented sector, often transitioning into owner-occupation or short-term letting. That does little to address the underlying supply imbalance that forces many tenants to rely on substandard accommodation in the first place.
"As a sector, we need to be honest about what progress actually looks like," said Sián Hemming-Metcalfe, operations director at Inventory Base. "A 20% reduction sounds positive, but if that change is driven by landlords leaving rather than properties improving, we are not solving the problem, we are reshaping it."
"Increasing that rate of improvement to 30% would require fully funded enforcement, consistent penalties, and a level of reinvestment that current margins simply do not support. On the current trajectory, 20% is realistic. However, the concern is that even this outcome leaves hundreds of thousands of tenants in non-decent homes."
