Downie's cottage

The Building

Building post-intervention

This project was the refurbishment of an early 19th C croft house located near Braemar in the Cairngorms National Park (UK), Downey's Cottage. It is an exceptionally rare and important survival of the open hearth tradition of vernacular building in the North East of Scotland. This simple 3-bay cottage is remarkable for its largely intact interior with traditional plan arrangement with rooms to E and W and a central core comprising box-beds and a stair to the roofspace. It is Category A listed (highest protection in Scotland).

More Details

The Solution

Solution pre-intervention

What is the Solution?

Modern float glass, 6mm thick was used in repairing both sash windows. In order to comply with Building Control requirements to ensure that the building could be evacuated via the windows in case of fire in the porch, the upper sashes had to be adapted to form casements; this require Listed Building Consent.

Why Does it work?

There were two principal windows on the front elevation serving each of the core rooms with a further very small window in the rear elevation serving the small bedroom area behind the stair. The two sash style windows appeared to be original and matched those pictured in the 19th century photographs. The upper sections were sound, but new sills and stiles were required. Due to their small size, and their history, they were repaired like-for-like with no thermal improvement required by Building Control. There were no early glass panes remaining. Older glass, especially that from pre-1880 can be thin (down to 3mm), and it is likely to have been damaged at some point.

PROS

High heritage preservation standard, with the repair of the original windows and the use of floated glass
No significant visual change, with a like-for-like repair
Repairs improved airtightness

CONS

No thermal improvement, based on the their small size and their history
Airtightness could have been even more improved by adding sealant
Thermal comfort near the windows still not improved, because it still radiates cold.

Window Type before retrofit

Casement Window

Window glass type

Floated single glazing

Window frame material

Wood

Window position

In the middle

Shading

No shading device

Health issue

While sanding down the window in order to return to its original state before re-painting it, old lead paintings may be found. Solutions exist to protect carpenters health in this situation.

Additional documentation

refurb-case-study-22.pdf

Installation Method

The windows were removed and cleaned down back in the workshop.

Moisture Management and Technical Compatibility

Condensation will inevitably occur due to single glazing and low exterior temperature in Scotland. Moisture will have to be managed by occupants, as it was in the past. For example, wipe off condensed water from glass before run-off every morning in order to avoid wood decay. This constitutes a sustainable answer to moisture problem, as long as the occupants are willing to live in a Category A listed building.

Airtightness

There is no real strategy about airtightness, what seems to be a missed opportunity.