Protimeter Revisited for Large Scale Damp Investigations
By: Dr ANTHEA AIREY BSc(Hons) PhD MBA MRACI CChem – Project Leader, Scientific Services – Airey Taylor Consulting
Summary:
Damp in structures precedes eventual rusting. “Protimeter Survey-master” is a non- destructive testing instrument favoured by building inspectors assessing bathroom leaks and the like. The Protimeter measures the reflected radio frequency signal some 10-19 millimetres into concrete or other substrates, providing a dimensionless result for moisture that is dependent on the calibration supplied by the manufacturer. The proprietary nature of the instrument’s operation and calibration can thus potentially pose an issue for expert witnesses. Case studies herein comprise housing, commercial and community structures that were investigated with firstly a hand held combined moisture/temperature/surface relative humidity meter, the Protimeter, and by means of in-slab relative humidity tests.
The investigations in Perth’s summer of 40 percent relative humidity confirmed that moisture transiting slabs and walls can be primarily gaseous and registering as “dry” in either surface moisture content or surface relative humidity tests, but with the aid of the Protimeter easily diagnosed. The results of the modern case studies suggests sub-slab vapour barriers are generally both designed and constructed but there is a tendency to overlook the need to wrap the vapour barrier around the edges of slabs and footings, causing a modern chapter of 19th century rising damp problems to recur.
This paper was published in Corrosion and Prevention Issue 136 in 2014. The first page is available here; further information upon request from Airey Taylor Consulting.
