The architect behind a controversial proposal to demolish a 150-year-old townhouse in the heart of Sliema has pledged to revise his plans to ensure its important architectural features are preserved and retained.

The house in Cathedral Street, within the Sliema Urban Conservation Area, had been targeted for complete demolition to build a new six-storey apartment block.

The application was vehemently opposed by residents and NGOs, as well as the Superintendence for Cultural Heritage (SCH), which noted after an on-site visit that the house contained various internal architectural elements which demanded preservation.

Architect Colin Zammit told the Times of Malta yesterday that in light of the SCH assessment, he wrote to the Planning Authority to revise his plans and retain the internal structure of the existing house, ensuring the preservation of its architectural features.

They include a stone coat of arms, an elaborate stone staircase, an ornate niche in the garden

Mr Zammit was contacted after Flimkien Għal Ambjent Aħjar questioned why the internal features had not been included in photos submitted to the PA as part of the application, which it described as an “abusive attempt to hide the heritage value of the property”.

“The stately home is laden with irreplaceable features of historic and architectural value,” FAA said in a statement, “among them a stone-sculpted coat of arms, an elaborately detailed stone staircase, a barrel-vaulted well and an ornate niche at the far end of its mature back garden.”

The townhouse in question is part of a well-preserved row of houses commissioned by the Mdina Cathedral between 1870 and 1886 for clergymen coming from renowned families.

Objectors have argued that approving the application would irreversibly alter the streetscape and destroy the character of the surrounding townhouses, as well as setting a precedent for further destructive development in the street. Architect Edward Said, president of the Sliema Heritage Society, has called for the townhouse in question – Number 33 – to be scheduled, and noted that similar buildings nearby had recently been restored to be used as residences.

“Cathedral Street has over the past decades lost much of its original splendour to development,” Mr Said wrote, “however four of its finest stately properties still survive as a well­-preserved row, together with a smaller townhouse designed by the acclaimed Art Nouveau exponent Giuseppe Psaila (architect of Balluta Buildings) which abuts No. 33.”

Sliema has seen a marked increase in applications for apartment blocks and guesthouses in place of traditional townhouses over the last year, partly due to changes in planning procedures.

This has raised concern over the fate of the town’s few remaining undisturbed streetscapes.