The Court decision in Duval v 11–13 Randolph Crescent Ltd [2020] has become one of the most important leasehold cases for anyone seeking (or granting) a Licence for Alterations in a block of flats. In short, it limits when a freeholder can safely give consent—particularly where the lease contains absolute prohibitions on certain works and the leases include mutual enforceability provisions.
It matters because it can turn what looks like a straightforward “just get a licence from the freeholder” situation into something that may require a lease variation or wider leaseholder agreement, especially for structural works.
(General information, not legal advice. Always take legal advice on your specific lease wording and proposed works.)
1) The key idea in Duval (in plain English)
Many leasehold blocks are set up so that each leaseholder has comfort that:
- everyone in the building is bound by similar covenants (e.g., restrictions on alterations), and
- if one leaseholder breaches those covenants, the freeholder/landlord will enforce them if asked.
In Duval, the Supreme Court considered whether a landlord could grant a “licence” allowing one leaseholder to do works that would breach an absolute covenant in the lease—when the landlord had also promised other leaseholders that it would enforce those covenants.
The Court’s answer was effectively:
No—if the lease absolutely prohibits the work, and the lease structure requires the landlord to enforce covenants for the benefit of other leaseholders, the landlord cannot lawfully “license” that breach without putting itself in breach of its promise to the other leaseholders.
2) Why it’s such a big deal for Licences for Alterations
Before Duval, the “common assumption” (in many buildings)
A lot of people assumed that if you could persuade the freeholder to sign a licence, that was the end of the matter.
After Duval, a licence is not always enough
Where a lease contains an absolute covenant (a strict “you must not do X” with no consent route), the landlord may not have the power to grant a licence that authorises that breach—if doing so conflicts with the landlord’s obligations to other leaseholders under mutual enforceability arrangements.
This is why some freeholders and managing agents have become more cautious about approving structural works—even if the leaseholder is willing to pay fees and provide drawings.
3) What kind of lease wording triggers Duval risk?
Duval most commonly bites where you have both:
A) An absolute prohibition (or a truly “absolute” part of the lease)
This is wording that bans certain works outright, for example:
- “Not to cut, maim or injure any wall…”
- “No structural alterations…”
- “No alterations whatsoever…”
In Duval, there was an absolute covenant preventing cutting into structural elements (walls etc.) and the proposed works involved removing part of a load-bearing wall.
B) A mutual enforceability / enforcement promise
This is wording that, in effect, means:
- leases are on similar terms across the block, and/or
- the landlord promises to enforce covenants against other leaseholders when requested.
This mutual enforceability structure is exactly what created the problem for the landlord in Duval.
If both features are present, the landlord may be constrained from granting a licence that permits a breach of an absolute covenant.
4) Does Duval stop all Licences for Alterations? No.
A really important distinction is the difference between:
Absolute covenants (hard stop)
If the covenant is absolute, there’s no built-in “consent route” in the lease for that type of work. This is where Duval can cause major problems.
Qualified / fully qualified covenants (consent route exists)
If the lease says something like:
- “not without the landlord’s consent” (qualified), or
- “consent not to be unreasonably withheld/delayed” (fully qualified),
then (generally speaking) the lease already contemplates the landlord granting consent, and Duval is far less likely to be the barrier. Commentary on Duval consistently draws that line: the case is principally about licensing breaches of absolute prohibitions where the lease structure depends on enforceability between leaseholders.
5) What it means in practice for common types of works
Structural alterations (highest Duval risk)
Examples:
- removing walls / forming openings
- installing beams / steels
- cutting into slabs, joists, structural masonry
These are the classic scenarios where leases often include absolute wording and where freeholders may be unable (or unwilling) to consent post-Duval.
Hard flooring / acoustic changes (depends heavily on your lease wording)
Some leases treat floor coverings under a “nuisance” covenant, some have express flooring restrictions, and some treat it as an alteration. Duval becomes relevant if the flooring restriction is genuinely absolute and tied into mutual enforceability provisions.
Windows and external appearance changes (often controlled anyway)
Window changes are typically restricted by exterior/appearance covenants and building policies. Duval may be relevant if the restriction is absolute and the lease structure requires the landlord to enforce it for the benefit of others.
6) What about retrospective licences and historic consents?
This is one reason Duval caused such concern in the leasehold world.
If a landlord has already granted a licence that purports to authorise works that were absolutely prohibited (in a building with mutual enforceability arrangements), there is a risk that another leaseholder may argue that the landlord:
- acted outside its powers, or
- breached its enforcement obligations.
Practical commentary around the case notes that older licences may still be open to challenge in the right circumstances.
That doesn’t mean every historic licence collapses automatically—but it does mean the paperwork and the lease structure matter a lot more than many people assume.
7) If Duval applies, what are the usual solutions?
If your works fall into a “Duval risk” category (absolute covenant + mutual enforceability), the routes are typically more involved than a standard licence, for example:
A) Redesign to avoid the absolute breach
Sometimes the simplest route is changing the scheme so it stays within what the lease permits.
B) Formal lease variation (often the cleanest route)
Where the lease absolutely prohibits a particular type of work, the most robust solution is often to vary the lease terms (and sometimes related leases). That can mean deeds of variation and, depending on the building, wider leaseholder engagement.
C) Wider agreement / consents (building-specific)
Some buildings may be able to regularise risk by obtaining consents from relevant parties (how this is done properly is legal territory and depends entirely on the lease structure).
The point is: where a landlord cannot safely “license” an absolute breach, you usually need a route that changes the underlying permission position, rather than relying on a consent letter alone.
8) A quick self-check: is Duval likely to matter for my project?
Duval is more likely to be relevant if all of the following are true:
- your proposal involves structural work or something the lease strictly forbids, and
- your lease wording is absolute (no consent route), and
- the leases in the building are designed to be mutually enforceable through the landlord (i.e., the landlord must enforce if asked).
If you only have a standard qualified/fully qualified alterations clause (“consent required”), then the issue is more likely to be about reasonableness, fees, and conditions—not Duval.
The takeaway
The Duval case matters because it confirms a practical reality in many blocks:
A freeholder cannot always “fix” a prohibited alteration by signing a Licence for Alterations.
Where the lease absolutely prohibits the work and the block relies on mutual enforceability, the freeholder may be legally constrained from giving consent—and other leaseholders may be able to force enforcement.
That’s why getting the lease wording and building structure checked early can save time, cost, and conflict.
Need help understanding whether Duval affects your planned alterations?
Email mail@howorth.uk or call 07794 400 212. If you share (1) the exact alterations / “waste” / “no cutting” clause from your lease and (2) a short summary of your planned works, we can help you identify whether the covenant is absolute or qualified, what freeholders typically require, and the most practical route to consent in your type of building.