This property is located in what would have been the original grounds belonging to Manadon House. In 1940 the R.N.E.C. (Royal Naval Engineering College) acquired the site and constructed new buildings to train their officers and in 1946 it was named H.M.S. Thunderer. Manadon house then became the home of the Admiral. The Navy left in 1995, the grounds were sold off to create new housing, and this building was then converted into residential use. It is maybe one of the oldest houses in Plymouth and this chapel-like building could possibly of been built as a place of worship for the main house around 1680. During the time the Admiralty were here, this building served as the offices for the D.O.E. (Department of Environment) who were in charge of carrying out maintenance on the camp.

We have carried out additional work here in the past, and one of those jobs involved putting in a new apron  out of granite which  leads into the property along with a decorative threshold to the front door entrance. This time though, some cracks had appeared on the corner of the property, and we were asked to put this right.

Someone had tried to patch this corner in at some point in time, but they had used a cement mortar and the stones weren’t even tied in properly. We decided to take out the cement and set in some stainless steel helical straps. These straps are set into the bed joints of the stonework. They are set in at a depth of 50mm and they span 500mm either side of the open crack. In this case we returned the straps around the corner. Our first job was to cut these joints out and get them prepared. The straps are positioned about 300mm apart and three joints were cut out.

Once the preparation work had been carried out it was time to put in the straps.

These are set in place with epoxy resin anchor mortar.

The epoxy is kept back about 25mm from the face of the stonework to allow for re-pointing.

We also drilled and fixed some 500mm stainless steel helical pins through some of the quoin stones to give extra lateral strength.

The epoxy resin sets within fifteen minutes or so and everything is then tied back in nice and solid with no movement within the stonework. We then finished off by re-pointing the joints to match existing.

And once that all dried out it matched in pretty well.

This system of using helical straps for situations like this are a perfect fix. They are quick, economical and when done correctly, they are classed as a structural repair.