Quastels LLP is pleased to have acted for the successful Appellant in Oakwood Great Oak Ltd v HMRC [TC/2024/03198], a decision of the First-tier Tribunal (Tax Chamber) issued on 5 August 2026. The case is an important addition to the growing body of case law on when a building ceases to be “suitable for use as a dwelling” for the purposes of Stamp Duty Land Tax (SDLT), and provides welcome clarification on how the Court of Appeal’s recent guidance in Mudan should be applied to severely deteriorated properties.
Background
The case concerned the SDLT treatment of the purchase by our client, Oakwood Great Oak Ltd, of “Great Oak”, a substantial detached house on Prowse Avenue, Bushey Heath, for £2,400,000 on 29 November 2022.
The Appellant filed its SDLT return on the basis that the transaction was non-residential. HMRC disagreed, opened an enquiry, and ultimately issued a Closure Notice concluding that the property was “residential property” within section 116(1)(a) of the Finance Act 2003 (FA 2003), a conclusion it maintained on review, prompting the Appellant’s appeal to the Tribunal.
The distinction matters a great deal in practice. If a property is “residential property”, SDLT is charged at higher residential rates (and, in the case of corporate purchasers, potentially at higher flat rates for high-value residential acquisitions, or an additional surcharge in certain cases). If the property is instead non-residential (because it is no longer suitable for use as a dwelling) the lower, non-residential rates apply. For a derelict or heavily dilapidated property acquired as a development opportunity, the difference in tax exposure can be very substantial.
The Legal Test: Section 116 FA 2003 and the Mudan Guidance
Section 116(1)(a) FA 2003 defines “residential property” as “a building that is used or suitable for use as a dwelling, or is in the process of being constructed or adapted for such use”. The definition of “dwelling” in Schedule 4ZA FA 2003, which governs the higher rates chargeable on additional dwellings, is in the same terms, save that it applies to a “single” dwelling.
A recent authority on this test is the Court of Appeal’s decision in Mudan v HMRC [2025] EWCA Civ 799, upholding the Upper Tribunal’s decision in Mudan v HMRC [2024] UKUT 307 (TCC). In Mudan, the Court of Appeal firmly rejected the argument that a property must be capable of immediate occupation to be “suitable for use as a dwelling”, holding that this would improperly read words into the statute that are not there.
Instead, the Court of Appeal held that the criteria are focused on the “fundamental characteristics and nature” of the building, rather than a snapshot assessment of habitability at the effective date of the transaction. Where a building has previously been used as a dwelling, a key question is whether or not it has lost that character by the relevant date.
The Upper Tribunal in Mudan (endorsed on appeal) set out seven considerations relevant to assessing the impact of necessary works on suitability for use as a dwelling:
- whether the building was previously used as a dwelling;
- where it sits on the range between a “desirable house” requiring updating and an “empty shell”;
- whether the required works are aimed at habitability rather than mere improvement;
- whether identified defects are capable of remedy without being so hazardous as to prejudice their own viability, or without compromising structural integrity;
- whether occupation would be unsafe;
- that whether a repair is ‘minor’ or ‘fundamental’ is relevant but not particularly informative; and
- ultimately, whether the works needed mean the building no longer has the characteristics of a dwelling.
Critically, the Upper Tribunal and Court of Appeal both stressed that this is a multifactorial, evaluative assessment and that no single factor, including the theoretical possibility of fixing defects, is determinative.
The Facts
Great Oak was originally built in the 1930s as a substantial detached dwelling house, with a two-storey extension added in the 1960s, and had been used as a dwelling for many years. By the effective date of the transaction, however, it had stood vacant for approximately three to four years.
The Tribunal found that the property had deteriorated substantially during that period of vacancy, with widespread damp and mould, water ingress, cracking, deteriorated internal finishes, boarded or damaged windows, and defects affecting building services and utilities, alongside signs of vandalism or unauthorised access.
Competing structural evidence was before the Tribunal: reports commissioned by the Appellant identified significant damp, cracking and structural movement and concluded the property was not habitable in its then condition, while a report commissioned independently by the local planning authority took a more optimistic view of the main house but nonetheless identified serious concerns regarding the rear terrace, retaining wall, and the two-storey extension.
Perhaps the most significant feature of the case was the extensive presence of asbestos-containing materials throughout the property, including in the basement, service areas and roof void, falling within the highest risk category and necessitating licensed contractors, negative-pressure enclosures, air monitoring and clearance certification before safe occupation, repair or demolition could proceed. Crucially, the Tribunal found that removing the asbestos-containing materials would itself require the removal of associated services and building elements, generating a further need for substantial reinstatement works before the property could again function as a dwelling.
A costing report obtained by the Appellant estimated remediation costs at approximately £2.25 million, a figure the Tribunal treated with some caution as to precision, but accepted as persuasive evidence of the exceptional scale of intervention that would have been required.
The Parties’ Positions
The Appellant argued that the cumulative effect of the structural defects, extensive deterioration and widespread asbestos contamination meant the property had ceased to possess the characteristics of a dwelling and had, in substance, become a development site requiring demolition. Counsel submitted that the assessment of “viability” endorsed in Mudan and Ridgway could not sensibly exclude financial and practical considerations, and warned that HMRC’s approach (under which a building remains residential unless it has physically collapsed or repair would itself cause collapse) would create a perverse incentive to demolish buildings before completion.
HMRC submitted that economic viability formed no part of the statutory test, and that a defect which was capable of remedy was “fixable” regardless of cost. HMRC maintained that the main house remained structurally sound, that the asbestos had in fact been successfully remediated, and that the property therefore retained its residential character throughout.
The Tribunal’s Decision
The Tribunal allowed the appeal, finding that the property was not “residential property” in accordance with section 116(1)(a) FA 2003 at the effective date.
The Tribunal accepted that a number of factors favoured HMRC’s position: the property had been designed, built and used as a dwelling for many years, remained physically standing, and retained a recognisable residential layout at the effective date. The Tribunal also found that the property was not at imminent risk of structural collapse and that repair was not physically impossible.
However, the Tribunal’s reasoning turned on a crucial point of principle. It rejected the proposition that the statutory question is answered simply by asking whether a property is theoretically capable of repair, observing that: “Almost any standing structure can be said to be capable of repair if one assumes the availability of unlimited time, resources and expenditure”, and that such an approach would risk depriving the statutory test of any meaningful content. Instead, the practical consequences and exceptional scale of the required works were relevant to the ultimate question of whether the building retained the characteristics of a dwelling. The Tribunal placed particular weight on the asbestos contamination, finding that its remediation would not simply have made the property safe while leaving it otherwise intact, but would itself have generated a further need for substantial reinstatement works before the property could again function as a dwelling. The Tribunal emphasised that these factors had to be considered cumulatively rather than in isolation: viewed individually, no single defect was decisive, but viewed together, they presented a materially different picture. The Tribunal weighed all the relevant factors and concluded that the cumulative effect of all the issues with the property meant it had “crossed the line” contemplated in Mudan and was no longer suitable for use as a dwelling.
For any other questions on the case, or tax appeals more generally, please contact the Private Wealth and Tax team at Quastels.
