Craigievar Castle, Alford | Restoration Case Study

Our role: Principal Contractor
Client: National Trust for Scotland
Restored: 2010
Awards: Aberdeenshire Design Awards 2010: Distinction for Craftsmanship and Highly Commended for Conservation

Craigievar Castle is a Category A listed tower house completed in 1626 by William Forbes and widely regarded as one of the finest examples of Scots Renaissance architecture. As Principal Contractor for the National Trust for Scotland, we removed its impermeable cement harl and returned the castle to the lime harling and distinctive pink limewash it was built with.

Before & after

Drag across the image to compare the building before our work and after completion.

Craigievar Castle after restoration by LTM Group

BeforeAfter

The challenge

The cement harl was trapping moisture in the walls and causing damp inside, including damage to the castle’s ornate plaster ceilings. A cement slurry bonding coat had also been applied to the granite rubble beneath. The confined site restricted access and required programmed deliveries, and regular visits from the client and interested groups had to be accommodated safely within the compound.

Our solution

Our masons removed all of the cement harl by hand to protect the historic masonry, and after trials a light grit blast was agreed as the right way to remove the slurry from the granite. Mortar analysis showed the originals were feebly hydraulic hot lime mixes, so the new harl was hand cast with a Scotch harling trowel using hot lime. The limewash was made from finely ground quicklime with natural earth pigments to recreate the pink finish. A fully enclosed scaffold, tied to the ground rather than the building, avoided damage from fixings, and our stone conservator conserved the castle’s historic granite and sandstone carvings.

Outcomes

A breathable building again

Traditional hot lime harling and limewash let the walls dry out and protect the interior plasterwork.

23 carved cannons

Twenty LTM masons and apprentices carved 23 new decorative cannon spouts, designed by RCAHMS illustrator John Borland and described by the BBC as one of the biggest stone-carving projects undertaken in Scotland.