Stiff & Trevillion’s plans for Bloomsbury roof extension approved

Stiff & Trevillion’s designs for a rooftop extension to the headquarters of the Royal National Institute of Blind People (RNIB) have been given the go ahead despite a warning from Historic England that they could degrade the character of the local area.

Camden council voted seven for and one against to back the planning officer’s recommendation to approve the scheme at 105 Judd Street in the Bloomsbury Conservation Area, just south of St Pancras station.

It has been brought forward by 105 Judd Street Limited, which bought the building in January 2021. The RNIB have chosen to move to different premises which are easier to access and navigate for the visually impaired.

The scheme will add nearly 2,000sq m of lab-enabled office space to the building housed in a two-storey mansard roof extension, along with a new lift core and roof terraces on three levels. The entrances will also be redesigned and the building’s facades will be refurbished.

Three quarters of the original red brick building, which dates to the 1910s and 1920s and was originally the trade headquarters of the Salvation Army, will be retained under the plans. 

Stiff & Trevillion said the proposals use a “reuse over replace” approach which will save 2,500 tonnes of embodied carbon compared to a demolition and rebuild.

The planning officer’s praised the plans for representing a highly sustainable form of development and being in line with the council’s preference for reuse over rebuild on sites where that is a viable option.

The report added that the designs were of a high quality that respected the original character and proportions of the existing building and the surrounding conservation area.

But Historic England said the roof extension would “considerably and conspicuously” increase the scale and height of the building and possibly lead to an incremental change to the character of the conservation area.

“Substantially increasing the size of historic buildings set within the Bloomsbury Conservation Area in order to accommodate demand for development could bring a lot of incremental change to its character and appearance such that it would risk cumulative harm to its significance,” the group said.

Local groups also criticised the plans, with the Bloomsbury Residents Association Group saying the addition of the “intrusive” roof extension was “completely out of keeping with its surroundings”.

The Bloomsbury Conservation Areas Advisory Committee added that design for the mansard roof would make the building look “top heavy”, and said the extension would need to be set back and reduced to a single storey to avoid damaging nearby listed buildings.

While the site is not listed, it adjoins two grade II-listed terraces. It is located about 250m from AHMM’s £1bn R&D centre for pharmaceutical firm Merck, which was approved last year.