Planning – Application Comments

Consultation Date: Mon 13 Jan 2025

Consultation Date: Mon 13 Jan 2025

Comment Date: Tue 11 Feb 2025

Thank you for consulting Historic Environment about the above listed building consent application for the replacement of an atrium rooflight on the grade II* listed Archway Block (NHL ' 1117103), within the RM Stonehouse Barracks complex. Plymouth City Council Historic Environment was involved in extensive discussions on site in 2023 which resulted in the submission and LB consent issued under reference 23/01422/LBC which included the full replacement of the atrium rooflight to which this application relates.

The acceptability of replacement and the principle of the development has already been established in the 2023 application. However, this application seeks to supersede the 2023 consented design with an atrium design that deviates from the approved scheme. It is not clear why the consented 2023 scheme has not be delivered as agreed. The submitted 'Heritage, Design and Access Statement' states that "it has been agreed that further improvements to the water proofing details are required to improve longevity of the skylight", before failing to identify what these waterproofing improvements actually are! Following a review of the consented 2023 proposal and this latest iteration, it appears the 'improvements' are the introduction of double glazed panes as opposed to Georgian style wired glazing, and the introduction of an EDPM damp proof course that links with a new lead flashing detail to the upstand.

We note that the submitted 'Heritage, Design and Access Statement' claims that the new design is "aesthetically like-for-like", it is not clear what is meant by aesthetically like-for-like, either it is an exact replica ergo like-for-like or it is an alteration that looks broadly similar. The replacement of existing Georgian wired single glazing for double glazing will clearly alter the aesthetic and therefore cannot be considered like-for-like. No justification or explanation for the new double glazing specification has been submitted, as a grade II* listed building the introduction of modern glazing, even if discreet needs to be justified. Further to that the atrium construction, specifically the frame construction appears to have been simplified when compared to the consented 2023 scheme.

The introduction of an EDPM DPC below the cill that joins a newly proposed lead flashing is not in itself a concern, that being said we note that in the 2023 scheme all lead work was specified as code 5, this submitted scheme specifies code 4. Given the overall aim of improving water resistance and longevity we would like to understand why the lead specification has been downgraded to a reduced lead standard.

We are concerned that the proposed new atrium design is in fact aimed as cost reduction rather than improving longevity and is therefore a regressive proposal that fails to replication the existing structure accurately. As previously stated there is no justification for the design changes within the 'Heritage, Design and Access Statement', as such we request the following additional information prior to any final recommendation.
1. Why has the fenestration specification changes and what is the justification for the introduction of double glazing within this grade II* listed building.
2. If longevity is the aim of the proposal why has the lead specification changed from code 5 in the consented scheme to code 4 in this submission.
3. What is the full list of 'improvements' proposed, this is not explicitly made clear within the submitted information.

When considering developments that affect a designated conservation area, the Local Planning Authority shall give special attention to the desirability of preserving or enhancing the character or appearance of that area, as set out in Section 72 of the Planning (Listed Buildings and Conservation Areas) Act 1990. Any harm to, or loss of, the significance of a designated heritage asset (from its alteration or destruction, or from development within its setting), requires clear and convincing justification, NPPF16 Para 213.
The works as proposed within this application are considered to result in less than substantial harm to the significance of the heritage asset, however as stated less than substantial harm still requires clear and convincing justification. The proposal appears to result in harm to the historic accuracy of the atrium construction, whilst the aesthetic value is one consideration, so is the inherent value of the original structure design. The public benefit resulting from the proposal is considered to be moderate, we are keen to reduce instances of water ingress that would result in decay to the internal building fabric within the Archway Block.
In weighing up the impact of the development on the significance of the designated heritage asset and the public benefit resulting from the proposal, Historic Environment find the proposed development unacceptable without further information and justification as detailed above.