Case Studies

Three Gables

This house was built in 1880 to house tenants on a local estate. It is of solid brick construction, using hard, locally-made, 230mm thick bricks.

The walls had a rising damp problem up to 1m 22cm high. As a remedial measure, the walls had been lined internally with hardboard cladding on timber battens. This cladding had become saturated and had to be removed before insertion of the FREEZTEQ damp-proof course.

Treatment of external walls was from the outside. Internal 114mm walls were drilled from one side only.

Edworth Church

This church was built circa 1200 A.D. Construction is a random course stonework of a particularly hard stone (ironstone-cobbles). Wall thicknesses vary from 685mm to 1220mm. The FREEZTEQ system was used in 1974 to eliminate rising damp from the building.

Longstreet Road - Hanslope

Built in 1935 with bitumen damp-proof course, these houses were extremely damp due to breaks in the bitumen and to solid floors which had been put in during the Second World War to replace suspended floors, with consequent partial bridging of the original bitumen damp course.

Only the external walls were treated, which were solid 230mm fletton bricks.

Ashridge House

A Composite Wall Base

A section of wall built in Early Gothic Revival style in the early 1800s which has a base of rubble. The external facing is of 50mm stone and the internal facing is a single skin of brick.

Water rising through this composite wall base and into the 508mm thick dressed stone wall above was causing deterioration to the stonework and making the inside of the building damp.

In places the survey and treatment for rising damp revealed that the external and internal skins of the rubble base were retaining infiltrated water and the whole construction was acting as a tank, with a considerable volume of water trapped in large voids in the rubble.

Treatment of this wall type and 13th and 15th century walls at Ashridge House was successfully carried out by the FREEZTEQ process in which holes were drilled into the base of the wall and ice sticks of frozen FREEZTEQ solution inserted and absorbed into the fabric of the wall as they melted.

Crevices

Sticks of frozen FREEZTEQ chemical solution have been found to be an effective and economical medium for dosing creviced walls because they melt slowly and the wall material absorbs the liquid solution before it can achieve enough volume to flow into the large voids.

The FREEZTEQ solution is water based and is absorbed whether the wall is wet or dry.

Buttresses

At Ashridge the composite wall bases included stone buttresses. Drilling in these exterior walls was carried right through the buttresses to within 25mm of the inside of the wall. In places this was to a depth of 1117mm. The other holes drilled in the wall are shown as pecked lines on the diagram below.