For further information on subjects related to this project, please see the following:

Relevant Publications

Natural Stone Database

Laser Scanning

Stone Types

Measuring Moisture in Stone

Related Research Groups and Projects

Photo Gallery




Relevant Publications

Andrade C., Alonso C. and Acha M. (1994) Chloride diffusion coefficient of concrete containing fly ash calculated from migration tests. Corrosion and Corrosion Protection of Steel in Concrete 2: 783 – 793.

Betts, N. L. (2002) "Climate change scenarios for Northern Ireland." In: Smyth, A. et al (eds.) Implications of Climate Change for Northern Ireland, SNIFFER, Belfast: 26 – 42.

Bonazza, A., Brimblecombe, P., Grossi, C.M. and Sabbionni, C. (2007) "Carbon in black layers at the Tower of London." Environmental Science and Technology 41: 4199-4204.

Buchwald, A. and Kaps, Ch. (2000) "The Ion Mobility of Deteriorating Salts in Masonry Materials of Different Moisture Content." Materials for Buildings and Structures. Euromat, 99, 6: 157-162.

Cassar, M. (2005) Climate Change and the Historic Environment. Centre for Sustainable Heritage, University College London.

Crawford, T. (2007) Future climate change : modelling the implications of shifts in rainfall characteristics for runoff in Northern Ireland. Unpublished PhD Thesis, Queen’s University Belfast.

Crispim, C.A, Gaylarde, P. M. and Gaylarde, C. C. (2003) "Algal and Cyanobacterial Biofilms on Calcareous Historic Buildings." Current Microbiology 46: 79-82.

Dornieden, T., Gorbushina, A A. and Krumbein, W. E. (2000) "Biodecay of cultural heritage as a space/time-related ecological situation — an evaluation of a series of studies." International Biodeterioration and Biodegradation, 46, 4: 261-270.

Gaylarde, C., Ribas Silva, M. and Warscheid, T. (2003) "Microbial impact on building materials: an overview." Materials and Structures 36, 5: 342-352.

Herrera, L.K, and Videla, H.A. (2004) International Biodeterioration and Biodegradation, 54: 125-134.

Hulme, M., et al. (2002). Climate Change Scenarios for the United Kingdom: The UKCIP02 Scientific Report.  

Jain, A., Bhadauria, S., Kumar, V. and Singh Chauhan, R. (2009) "Biodeterioration of stone under the influence of different humidity levels in laboratory conditions." Building and Environment 44: 1276 – 1284.

McAlister, J.J., Smith, B.J. and Curran, J.A. (2003) "The use of sequential extraction to examine iron and trace metal mobilisation and the case-hardening of building sandstone: a preliminary investigation." Microchemical Journal 74: 5 – 18.

Mitchell, R. and Gu, J-D. (2000). International Biodeterioration and Biodegradation, 46: 299-303.

McKinley, J.M., Warke, P.A., Smith, B.J. and Curran, J.M. (2006) "Application of geostatistical techniques in weathering studies of building stone." In: Fort, R., Alvarez de Buergo, M., Gomez-Heras, M. & Vazquez-Calvo, C. (eds.), Heritage, Weathering and Conservation. Taylor & Francis Group, London, 531 – 537.

NOAHS Ark (2007)  Production of the vulnerability atlas (

Ortega-Calvo, J.J. et al. (1992) Proc, 7th Int. Congress on Deterioration and Conservation of Stone, Lisbon, 1, 541-550.

Poupeleer, A.S. et al. (2003) International Journal for Restoration of Buildings and Monuments, 9: 663–682.

Richardson, B.A. (1995) Biodeterioration and Biodegradation l 9, 101-106.

Sass, O. and Viles, H. A. (2006) "How wet are these walls? Testing a novel technique for measuring moisture in ruined walls." Journal of Cultural Heritage 7: 257 – 263.

Shaát, A. (1994), Int. Conf. on Corrosion and Corrosion Protection of Steel and Concrete, 446-460.

Smith, B.J. and Curran, J.M. (2000) In: D. Rammelmair et al. (eds) Applied Mineralogy in Research, 67-70.

Smith, B. J., Turkington, A. V., Warke, P. A., Basheer, P. A. M., McAlister, J. J., Meneely, J. and Curran, J. M. (2002) "Modelling the rapid retreat of building sandstones: a case study from a polluted maritime environment." In: Seigesmund, S., Weiss, T. & Vollbrecht, A. (eds.), Natural Stone, Weathering Phenomenon, Conservation Strategies and Case Studies, Special Publications 205, 347 – 362. London: Geological Society.

Smith, B. J., Warke, P. A. and Curran, J. M. (2004) "Implications of climate change and increased ‘time-of-wetness’ for the soiling and decay of sandstone structures in Belfast, Northern Ireland." In: Prikryl, R. (ed.), Dimension Stone, Taylor & Francis Group, London, 9 – 14.

Smith, B. J., Warke, P. A., McGreevy, J. P., and Kane, H. L. (2005) "Salt weathering simulations under hot desert conditions: agents of enlightenment or perpetuators of preconceptions?" Geomorphology 67: 211 – 227.

Smith, B. J., Gomez-Heras, M. and McCabe, S. (2008) "Understanding the decay of stone-built cultural heritage." Progress in Physical Geography 32: 439 – 461.

Terheiden, K. (2008) Journal of Building Physics, 31: 199-211.

Thornbush, M., Viles, H.A .(2006). Science of the Total Environment. 367, 203-211.

Turkington, A.V. and Smith, B.J. (2000) Earth Surface Processes and Landforms, 25: 1317-1332.

Viles, H. A. (2002) "Implications of future climate change for stone deterioration." In: Seigesmund, S., Weiss, T. & Volbrecht, A. (eds.), Natural Stone, Weathering Phenomenon, Conservation Strategies and Case Studies. Geological Society, London, Special Publications, 205: 407 – 418.

Viles, H.A. and Wood, C. (2007) "Green walls?: integrated laboratory and field testing of the effectiveness of soft wall capping in conserving ruins." In: Prikryl, R. & Smith, B. J. (eds), Building Stone Decay: From Diagnosis to Conservation. Geological Society, London, Special Publications 271.

Wakefield, R.D., Jones, M.S. & Forsyth, G. (1996) "Decay of sandstone colonised by an epilithic algal community." In: Smith, B. J. & Warke, P. A. (eds.), Processes of Urban Stone Decay. Donhead, London: 88 – 97.  Welton, R.G. et al. (2003) Environmental Geochemistry and Health, 25: 139-145.

Whiting, D. (1981) Public Roads, 45: 101-112.

Wilby, R.L. and Dawson, C.W. (2007). SDSM 4.2 — A decision support tool for the assessment of regional climate change impacts, Version 4.2 User Manual, Nottingham: Environment Agency of England and Wales.

Young, M.E. (1997) Unpublished PhD thesis, Robert Gordon University, Aberdeen.




Natural Stone Database

This interactive database provides key information and images on building stone used on listed buildings and monuments throughout Northern Ireland, as well as the quarries (active and inactive) from which the stone was extracted. The database is the outcome of an Industry-Research Partnership of the architectural practice - Consarc Design Group (Dawson Stelfox MBE) and Queen's University Belfast (Prof. Bernard Smith) supported by Environment and Heritage Service (EU Building Sustainable Prosperity Programme). Please follow this link to the Natural Stone Database.

Stone Database Project logo




Laser Scanning

High definition laser scanning (and object scanning) can be used to analyse stone surfaces and monitor change. Past studies  demostrated that pore-filling by salts can be detected by object scanning, and scanning with high resolution will help us to understand the growth of biofilms over time, blocking pores and effectively sealing stone surfaces. Another useful aspect of laser scanning is the ability to quantify the reflectance of a surface - in essence, this will help us in objectively deciding if, and to what extent, a building 'greened'.





Stone Types

Sandstone is the construction material under investigation in this project. Three widely used sandstones are used in test walls and laboratory experiments - Peak Moor Sandstone, St Bees Sandstone, and Scrabo Sandstone. Each sandstone has different properties which will control how the stone responds to moisture and 'greening'. The use of these stones on buildings within Northern Ireland can be explored using the Natural Stone Database for Northern Ireland (see link above).

Peakmoor Sandstone is a Carboniferous Millstone Grit, quarried near Matlock in Derbyshire. It is medium grained and buff in colour. Examples of use include walling and dressing stone in restoration and new builds. For results of BRE standards tests, see the BRE Technical Data Sheet for Peakmoor Sandstone.

Close up view of Peak Moor Sandstone.

Cove Red Sandstone is from the New Red Sandstone of Triassic age. It is a fine-grained stone, and red to brown in colour with varying bed definitions.  Examples of use include Kelingrove Museum, Glasgow. For results of BRE standards tests, see the BRE Technical Data Sheet for Cove Red Sandstone.

Close up view of St Bee's Sandstone.

Local, clayey sandstone comes from the Upper Carboniferous Millstone Grit formation which outcrops in and around  the Dungannon area in Co. Tyrone. The sandstone is typically fine- to medium-grained and bedded, with colours and hues ranging from cream to greyish-white or grey to yellow. Although the quarries are largely inactive today, this sandstone was used extensively throughout Co. Tyrone and transported to Belfast when the railways were established. BRE test results for this sandstone are not published; however, Stanton Moor Sandstone is from the same geologic formation and appears petrographically similar. Therefore,  results from BRE standards tests for Stanton Moor Sandstone may be similar to those for the local, clayey sandstone.

Close up view of Dungannon Sandstone  




Measuring Moisture in Stone

The movement of moisture through building stone is a critical factor in both biotic and abiotic processes. Whilst moisture on the surface of stone is readily apparent (and easily measured), it is much more difficult to discover what is happening within the stone. This project uses a geoelectrical technique known as 2D electrical resistance tomography (ERT) to ‘see’ into building stone and infer moisture conditions at depth. The technique is based upon the relationship between electrical resistance, current, and voltage, and the fact that moisture readily conducts electricity. This implies the assumption that low electrical resistivity equals high moisture content and vice versa. In order to estimate the resistivity at depth, a known electrical current is applied to building stone using the Geotom, a combined power source, voltage meter, and switching device (the orange ‘suitcase’). The current is applied via an array of electrodes, in this case medical ECG electrodes, as these do not damage the stone surface. Measuring the voltage between different combinations of electrodes enable calculation of the resistivity and inference of internal moisture conditions. The2D Geotom surveys of moisture are augmented with surface moisture measurements, collected using a protimeter. Regular surveys of the study structure walls in Derrygonelly will reveal how moisture distribution through stone walls changes as the surface is colonized by microorganisms.

Nick with the Geotom, measuring moisture on the front facade of Elmwood Hall.   Results of Geotom measurements for front facade of Elmwood Hall.




Related Research Groups and Projects

Weathering Research Group, Queens' University Belfast

The Limestone Project: Understanding catastrophic decay of building limestone

The Giant's Causeway: Slope instability at a coastal World Heritage Site

Queen's Conservation Area Geomonumental Route

Oxford Rock Breakdown Laboratory




Photo Gallery

Below are some images of 'greening' sandstone, representing sites across Northern Ireland.

Greening of red sandstone pillar.      Image of greening stone at Haworth.





Thank you to our Official Advisory Panel:

Dr Claire Foley (NI Environment Agency)
Dr Ewan Hyslop (British Geological Survey)
Mr John Savage (Consarc Design Group Ltd)
Dr Joanne Curran (Consarc Design Group Ltd)
Dr Maureen Young (Historic Scotland)
Mr Chris Wood (English Heritage)



Engineering and Physical Sciences Research Council(EPSRC)logo
Queen's University Belfast (QUB) logo
Centre for Ecology and Hydrology logo
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