A bid to redevelop a Harpenden care home described as a “blot on the locality” has been rejected for a fourth time.

The plans, submitted by Beechcroft Developments, were unanimously refused by St Albans district council’s planning committee north.

The proposals would have seen the current semi-derelict site converted into a retirement housing scheme, including three flats in the existing building, two new build flats and four new mews houses to the rear of the property.

Officers had recommended the plans be approved, subject to conditions.

But councillors were concerned about the design of the mews housing to the rear of the current properties and impact on the town’s conservation area.

There were also concerns that the flat-roof of the new mews block would not be in keeping with the Victorian and Edwardian architecture of Salisbury Avenue, and was compared to an office block.

The newly built 23 Salisbury Avenue would have matched the current style of the road, but the design would not have extended to the properties in the rear of the development.

Councillors also raised concerns about the lack of car parking, and possibility of the flats overlooking current residents, although an inspector said this was not thought to be an issue.

Giles Brockbank, from agent Ridge and Partners, told the committee the applicants had worked with officers to ensure the plans met all relevant guidance: “I note the concerns that have been raised in relation to the rear block, but as part of the discussions we believe we have produced a successful contemporary addition to the conservation area.”

They added that they were happy to discuss concerns with the mews further if necessary, although the committee were told they could not defer the decision and had to choose whether to reject or approve the plans.

Despite a desire to restore the site, councillors said that it was important to get the decision right after the lengthy process.

Cllr David Heritage said: “[There are] many applications we’ve protected, turned down or queried over the years, always saying ‘the conservation area wherever possible must be protected’.

“This proposed building in the rear of 21 and 23 – and I do like what they’ve tried to do in 21 and the new building at 23 – I think destroys, really, the character of that plot. They’ve missed a trick here, something nice could be built there.

“Various people have mentioned it should be a single-storey, I agree with that completely and have a roof, not a flat roof. As someone else has mentioned, it looks very much like a commercial building in another part of Harpenden.”

The committee’s chair, Cllr Paul Cousin, said that he would feel more “sympathetic” to designs for a 1.5 storey development, rather than a two-storey development.

The committee unanimously refused the proposal.

The reason given for refusal, proposed by Cllr Roger Butterworth, was: “By reason of the design, poor quality, detailing and flat roof form of the rear mews block, together with its scale and massing, the proposal would appear incongruous in the street scene, and would fail to preserve or enhance the character and appearance of this part of the Harpenden Conservation Area and the setting of the locally listed building.

“The harm would be less than substantial when assessed against the National Planning Policy Framework, and that harm would not be outweighed would not be outweighed by public benefits in this case.”

Cllr Butterworth added that it failed to meet policies within St Albans Local Plan, Harpenden’s neighbourhood plan and national guidance.

Cllr Lisa Scriven called in the plans because she said the current state of the site is a “blot on the locality”.

According to a council report: “The current semi-derelict state of the site is a blot on the locality, so restoration of 21 Salisbury Avenue and removal of late 20th century accretions represent positive developments, with the benefit of additional retirement accommodation, is welcomed.

“However, following the previously refused applications for this site, this proposed development overall could still be considered in terms of scale, size, bulk and density to be an overdevelopment of the site and out of character with surrounding properties in this Conservation Area, detrimental to the existing balance of buildings in this and adjacent roads.”