What Is a Category A Office Fit Out?

Every commercial fit-out project moves through the same broad stages, though not every building starts at the same point. Understanding where Cat A sits helps make sense of what’s included, and just as importantly, what isn’t.

There’s no single legal definition of Cat A, and specifications vary between landlords and developers, but the following elements are consistently included in a standard South Wales Cat A scheme.

Cat A is almost always a landlord or developer-led project, not a tenant one. There are two common scenarios where it happens.

New Developments

A newly constructed office building is typically delivered to Cat A standard before it’s marketed, so prospective tenants can view a finished, lettable space rather than a bare concrete shell.

Refurbishment Between Tenancies

When an existing office becomes vacant, a landlord will often strip out the previous tenant’s Cat B fit out and refurbish back to a Cat A standard before re-letting — sometimes called “Cat A reinstatement.” This is directly connected to lease-end obligations: many commercial leases require the outgoing tenant to fund or carry out this reinstatement as part of their dilapidations liability.

Cardiff’s office market has a real split that directly affects what “Cat A” means in practice, and it’s worth understanding if you’re viewing space or specifying a refurbishment.

At the top end, new and newly-refurbished Grade A buildings in the Central Square and Callaghan Square core have pushed prime headline rents to roughly £30 per square foot, a level reached at buildings including One Central Square and Hodge House during 2025. Grade A space in this bracket is scarce relative to demand, and a Cat A scheme in a building of this standard is delivered to a genuinely high specification: strong sustainability credentials, modern services, and layouts designed around current tenant expectations from day one.

But Cardiff doesn’t have enough new Grade A stock to meet demand, which is exactly why landlords across the city have been refurbishing older Grade B buildings, city-centre stock typically dating from the 1980s and 90s, back to a Cat A standard. Buildings like Southgate House and Coal House are real examples: comprehensively refurbished, re-let at £18–20 per square foot, considerably below prime Grade A rent, but still delivered to a genuine Cat A specification.

For a tenant, this matters practically: a “Cat A” space in a refurbished 1990s building and a “Cat A” space in a brand-new Capital Quarter development can look and perform very differently, even though both are technically the same fit-out category. Older Grade B stock often has lower floor-to-ceiling heights, different raised floor void depths, and ceiling grids designed to older service standards, all of which affect how easily a tenant’s Cat B fit-out can be layered on top.

Beyond Cardiff: Newport and Swansea

The same principle applies across South Wales, though the mix differs by city. Newport’s commercial stock leans more heavily toward business park and industrial-adjacent buildings around Celtic Springs and Imperial Park, where Cat A specifications are generally more modern and consistent than Cardiff’s older city-centre stock, but mezzanine and warehouse-adjacent office space brings its own structural and fire compliance considerations into any Cat B works that follow. Swansea sits somewhere between the two: a mix of SA1 waterfront developments delivered to a modern Cat A standard, and older converted period buildings in the city centre and Uplands where the base condition varies far more from building to building.

Whether you’re a landlord specifying a Cat A scheme or a tenant planning the Cat B fit out that follows it, the same core interior systems need to be right. This is where our work sits, on both sides of that line.

We deliver both Cat A and Cat B interior packages across Cardiff, Newport and Swansea, working directly with landlords, letting agents, and incoming tenants depending on which side of the fit-out line the project sits on.

No, though the two are often confused. Cat A+ (sometimes called “plug and play”) is a more recent, higher-specification variant that’s become common in the post-pandemic “flight to quality” market, mostly in larger cities. A Cat A+ space typically includes elements that would traditionally be Cat B, such as meeting rooms, a basic kitchen or breakout area, and sometimes furniture, so a tenant can move in with minimal further work.

Cat A+ is less common in the South Wales market than in London or other major UK cities, where the higher upfront landlord investment is easier to justify against premium rents. Most South Wales commercial buildings are let on a standard Cat A basis, with the tenant commissioning their own Cat B fit out separately.