Materials Analysis

Charlestown Consultants have an in-house laboratory for building materials analysis and assessment, supported by external associated laboratories for more in-depth and alternative analysis procedures. As a result, we can now offer the widest range of building materials analysis and evaluation services available to the building conservation industry in Scotland.

We specialise in the analysis and evaluation of mortars plasters and renders, particularly lime based materials, using a wide range of analytical techniques.

Analysis of historic mortars can provide essential information to assist in the specification of compatible materials for conservation and repair work. This will be particularly relevant where patching and consolidation of historic mortars, plasters and other lime finishes are involved. Textures, colours and performance characteristics can be derived from analysis of historic materials, and used as the basis for developing appropriate specifications for conservation and repair works.

Analysis is also helpful in determining causes of materials failure, and may be used for research and archaeological purposes. It is imperative that the reasons for undertaking analysis of historic mortars are understood at the outset, to ensure the most appropriate procedures are undertaken to achieve successful results. This will maximise the amount of useable information derived from any analysis procedures.

There are numerous techniques for determining and characterising historic mortars, some of which are outlined below. Each technique should not necessarily be seen in isolation as, commonly, two or more techniques can be used to build a clearer, more accurate 'characterisation' of the mortar. It must be recognised that different historic mortars and constituents of mortars may require different types of analysis. Please contact us for advice.

• Microscopy
• Wet chemistry
• X-ray diffraction
• BS4551 analysis
• Petrographic (thin section) analysis
• Aggregate evaluation and matching for repair mortars:
• Stone analysis, evaluation & matching
• Analysis and evaluation of other historic building materials

Over the last 12 years, we have analysed over 4,000 mortar, plaster and render samples, including those from:

• Edinburgh Castle
• St Pancras Station, London
• Frank Lloyd Wrights’ Robie House, Chicago
• The Great Hall, Stirling Castle
• The White House, Washington DC

We now have the world’s largest archive of historic mortars and aggregates, and developed and maintain the Scottish Aggregates Database on behalf of Historic Scotland