Lime mortars are popular for restoration projects because they match original mortars and do not pose the problems of water trapping posed by modern hard cements. But lime mortars are not always as easy to use as modern cements.

Castle Cement have have addressed this problem with the supply of two tonnes of hydraulic lime to the £1.5million restoration of Chantry House in Henley on Thames.

Parts of the 600-year-old building were found to be in a parlous state and fund-raising projects are still being held in the town to raise money for the work that is being carried out.

A team of specialist builders is using traditional materials and methods during the restoration. Hydraulic lime was chosen for various challenging parts of the work because it sets harder and faster than lime putty and provides additional durability.

Hydraulic lime mortars are being used for the consolidation of a flint retaining wall within the lower ground floor area of the building. This wall retains a one-storey high bank of soil, which is part of the churchyard in the adjoining St Mary the Virgin Church.

The same mortar has also been used for bedding all the ridges and verges of the Chantry House roof.

All the mortars used in the project have been manufactured by Lime Technology Ltd and are sold under the brand name Limetec. The company is based just a few miles from the site of the Chantry House.

As long as an order is for more than 15 tonnes of mortar, it can be delivered to site in large, re-usable silos, the speciality of CPI Euromix.

By working together, Castle Cement, Limetec and CPI Euromix have been able to make hydraulic limes simple and available to all projects, both conservation and new-build, no matter what their size.

The Chantry House was once the home of chantry priests, who were paid to sing for the souls of aristocrats. Later it became a granary and a school.

A number of items of archaeological interest have been uncovered during the work, including a textbook dating from 1642, tokens enabling the bearer to cross the River Thames and coins.