Congress of Vienna chairs, Mount Stewart

In September 2015 we received the chair covers of ten chairs from Mount Stewart, County Down, Northern Ireland. Only the covers came to the Studio, as the chair frames were being treated at the property.

Room setting before conservation treatment   Chairs in situ before conservation treatment

The ten sets of covers are from a set of twenty-two Empire period chairs used at the 1814-1815 Congress of Vienna (a conference of European state ambassadors to set a long-term peace plan in Europe following the French Revolutionary Wars and the Napoleonic Wars).  The covers however are a later addition to the chairs and were stitched by nuns in Nantes in the early 1930s.

Each chair has three separate covers: a plain woven outside back and a needlepoint inside back and seat (a total of 30 textile pieces for the 10 chairs). Every inside back is unique, as it represents each ambassador and the seat represents the country they come from. The seats have recurring designs, as several ambassadors may have been sent by the same country.

Clancarty seat, inside back and outside back before conservation

The main objective of this project was to clean the covers and infill the losses, to ensure their future stability and to complement the re-gilded chair frames in line with the client brief. The project is part of the £8 million restoration project at Mount Stewart.

After an initial assessment of condition and damage, the covers were vacuumed to remove the dust and dirt from the surfaces. Following cleaning tests they were prepared for wet cleaning by protecting the edges and weak areas.

 Netting the unfinished edges   Weak silk areas protected with Reemay® on reverse

The wet cleaning was carried out in a made-to-size bath in our wet room. Over the course of one day one set of covers could be washed and laid out to dry overnight. Tests showed that the covers were very acidic and washing in a normal conservation detergent solution did not raise the pH.  A buffered wash solution set at pH5.8 helped raise the pH to a more stable level and also helped reduce colour loss from the silk and wool threads.

20. Bath set up

Set up for wet cleaning

The wet cleaning was carried out in different stages:

  • Pre-soak to wet out the covers
  • 3 wash baths with a conservation grade detergent and buffering chemicals
  • Rinsing after each wash bath
  • Up to 9 rinses after the last wash bath to remove all the detergent

Following tests, it was found that the engrained dirt could be loosened when carefully agitated.  A selection of brushes and a sponge were used for this during the wash baths.
19. Tools for wet cleaning

The tools and equipment used during wet cleaning were:

  • pH meter
  • Conductivity meter
  • Rubber suede shoebrush
  • Rubber dog toothbrush
  • Sponge

The needlework covers were dried on a suction table to prevent colour run from some of the less stable embroidery threads.

Wash bath samples

Samples of pre-soak, baths and rinses

39. Seat Duc de Noailles BC - Duc de Dalberg after wet cleaning

Duc de Noailles before wet cleaning and Duc de Dalberg after wet cleaning

In line with the client brief, after wet cleaning the areas of loss were filled in with stitching to bring the covers back to their original appearance. To achieve this the covers were mounted on an embroidery frame. Careful documentation was carried out and photographs taken before and after stitching to identify any new work.


Infill threads:

  • Anchor and DMC stranded cotton for silk areas
  • Gutermann Silk 303 for silk areas
  • Appleton’s Crewel wool for wool areas

 Clancarty seat mounted on an embroidery frame

 ‘Wessenberg’ before and after infill

Following treatment the covers were sent back to Mount Stewart to be reupholstered onto the newly re-gilded chairs.  We are now working on the remainder of the chair covers to complete the set.

Find out more about the chairs from our National Trust Collections online here