The works

External works, ground levels, surface drainage

Moisture-related maintenance work

Re-pointing of mortar joints

Re-rendering or plastering of walls

Internal wall insulation

External wall insulation

✓

Cavity wall insulation

Fit flue damper or flue balloon

Block flues

Window maintenance

Secondary glazing

Retrofit double glazing to external windows

Windows & external door replacement

Draughtproofing

High level of airtightness

Internal redecoration

Insulation of suspended timber ground floor

Replacement insulated solid concrete floor

Maintenance work to roof and drainage

Roof insulation on flat ceiling

Roof insulation on pitched ceiling

✓

Re-plumbing

New room heaters

Heating system replacement

Heating controls upgrade

Domestic hot water storage upgrade

Solar hot water

Re-wiring

Change to 100% low energy lighting

Standalone extract ventilation

Whole house demand control mechanical extract ventilation

Mechanical ventilation with heat recovery

External wall insulation

Existing walls are reported to be of mass concrete construction with composite brick/block walls to the ground floor façade. The walls were insulated externally generally with 200mm expanded polystyrene. The owner wished to maximize insulation depths to get the greatest benefit from the retrofit. Dry dash render panels and plaster band features were accurately replicated to the front façade with an acrylic render finish to the sides and rear.

The walls to the façade at ground floor level were insulated externally with 150mm expanded polystyrene and brick slip finish. (The difference in insulation thickness accommodated the brick slip thickness and brick cornice detail at first-floor level). Brick detailing, including the arch and projecting brick surround over the entrance porch, were replicated accurately from survey photographs with cut bricks.

The projecting nose of the existing concrete cills were cut and over-clad with powder coated metal cills with a thin insulation board layer to reduce the cold bridging effect at this detail. The window reveals were insulated with a thin insulating board to finish within the depth of the frame of the existing window (which were retained in their existing position within the wall).

The porch soffit and side walls were left uninsulated as the insulation thickness would have had an unacceptable visual impact on the stained glass entrance screen. This area is therefore a cold bridge with disproportionate heat loss compared to the insulated walls. See chapter 7.5.4 - porches, recessed porches & wind lobbies, in relation to this generic issue.

Similarly, the walls of the unheated garage were not insulated externally or internally to the walls adjoining the hall & kitchen. Ideally, the insulation should be extended to these heat loss walls of the main house as they adjoin an unheated space.

High

Significant level of intervention. See paragraph below - Impact of Works on the Architectural Heritage

Attic Insulation

The existing attic quilt insulation was topped up to a 300mm depth. Where the wall insulation was carried up to the existing eaves soffit, care was taken to ensure that the attic insulation overlapped the soffit at this point to avoid thermal bridging.

Low

All original fabric was retained