Harrow Council has been accused of "sitting back" and allowing construction work to commence on a block of flats in a historic conservation area - without planning permission.
Property developers The Jaspar Group is currently carrying out works to change The Power House in West Street, Harrow -on-the-Hill, from an office building to residential units.
Planning permission was granted to create 14 units within the Victorian building, which is situated within a conservation area to protect the views from the Grade I St Mary's Church.
But nearby residents became "uptight" when the Powerhouse roof was removed and works on the second storey were carried out - using expired planning permission.
Ken Smith, nearby resident and member of the Harrow-on-the-Hill Community Group, said: "Jaspar's approach seems to carry out the work and then try and get planning permission.
"Under Planning Developer rights, it gives you the right to change the use but not the building itself.
"As soon as they started to change the actual building, then you need to get actual planning consent still.
"What Jaspar have done, is they've used their planning developer rights for 14 units in the existing building, but they've stuck a second building on top to expand it to 18/19 units, when they only have consent for 14.
"If any residents of West Street even so much as want to install double glazing, that has to be approved, so how are Jaspar getting away with this?
"They've completely pulled the wool over the council's eyes and the council just sits back and says they're not going to do anything about it."
'Planning permission has expired'
Harrow Council say that undertaking any works that require planning permission, without first gaining planning permission – as is the case at The Power House – is a "significant risk for any developer."
Without retrospective planning consent, the council has powers to seek a reversal of any unacceptable works, at the developer's own cost.
A spokeswoman for Harrow Council said: "The Power House’s developer had originally gained planning permission for some second-storey works back in 2013.
"That planning permission has expired and is no longer valid.
"As a result, in effect, the developer has no planning permission at all for its current works.
"The developer has applied retrospectively for planning permission on the works they are currently undertaking.
"The council is considering that application now in accordance with the planning laws and regulations."
The Jaspar Group say its development will "enhance what was once a poorly maintained office building, using materials that are sympathetic to setting, with parking, bike and refuse stores provided onsite".
The company says it is building the extension under planning permission consent for a roof extension, gained in 2010 - which it says was deemed "extant in perpetuity" in an email from Harrow Council in 2014.
A spokesperson for The Jaspar Group said: "A planning application is due to be submitted to Harrow Council seeking planning permission for the construction of an additional five units at the site.
"This scheme has evolved through pre-application discussions with the council.
"14 units are being constructed on site, in accordance with prior approval consent.
"In addition, there is a roof extension being constructed under the 2010 permission.
"This is being built out in accordance with the approved drawings for that consent.
"Works for the additional units will commence upon receipt of planning consent."
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