Inside Southend’s former tax office: Explorers reach rooftop before conversion to hundreds of new flats

A group of urban explorers quietly gained access to the empty tower block at 21 Victoria Avenue in the city of Southend – then made their way through several floors, into the basement, and ultimately onto the rooftop.

The building, known as Alexander House, is a 16-storey former government tax office block constructed in the early 1970s.

Alexander House once housed regional offices for HM Revenue & Customs (HMRC). It occupies a prominent site at the junction of Victoria Avenue, Queensway and Baxter Avenue. In recent years the building has stood largely vacant, awaiting redevelopment.

Planning permission has now been approved by Southend-on-Sea City Council to convert Alexander House into a mixed-use scheme by developer Comer Homes. The approved scheme will deliver 557 new homes, premium ground-floor retail units and a public “pocket park”, all wrapped in a refreshed external façade and improved landscaping.

The redevelopment is split into five distinct zones – East Pavilion, West City, East Street, West Pavilion and East City – all built around the existing structure in order to minimise carbon footprint. Sustainability forms a core part of the design: electric vehicle charging points, a residents’ car club, biodiversity net gain and a sustainable drainage system are all included.

What the explorers found in the old Southend tax office

According to photographs and video footage captured by the group, the building’s internal shell remains largely intact: open areas of glazed façade, lift shafts, and the bare concrete frame tell the 1970s story of the building. The explorers entered the basement level and ascended to the rooftop – giving them panoramic views of the city skyline, including the nearby station and Victoria Avenue corridor.

Why this site matters for Southend city centre

Victoria Avenue has been undergoing major regeneration for a number of years, with several tall-building conversions and new apartment developments rising along the skyline. Local planning policy identifies the central area as a key zone for housing delivery, retail renewal and landmark buildings.

The transformation of Alexander House is viewed as a “gateway development” that will mark the final piece of the Victoria Avenue corridor. As Brian Comer, co-founder and chairman of Comer Homes, put it: “Alexander House is a notable landmark on the city’s skyline, so we are delighted that our plans to transform the site into something everyone can be proud of is a momentous occasion.”

Concerns and next steps

While the scheme clearly brings new life to a vacant building, some concerns remain – notably around parking provision, the size and type of apartments, and the impact of infilling a previously office-use site. For example, one councillor warned about “how they are going to organise” parking given the increase from 334 homes to 557 in the updated plan.

Because the existing concrete frame is being retained, and the external envelope largely re-skinned, the developer argues there will be energy-bill savings for residents and a lighter carbon-footprint than a full demolition.

According to council filings, the application was judged not to require a full environmental impact assessment – meaning the project may proceed more quickly.