34th Meeting of the Programme Task Force Zagreb, 25-27 April 2018 Methods to calculate costs of corrosion and soiling of materials due to air pollution Pasquale Spezzano ENEA, Italy ICP Materials 34th Meeting of the Programme Task Force Zagreb, 25-27 April 2018

Surface restored Total cost Unit cost (m2) (M€) (€/m2) Recent maintenance/restoration costs for cultural heritage objects selected in Italy for the Call for Data Surface restored Total cost Unit cost (m2) (M€) (€/m2) Colosseum 13 300 6.1 458 Rome Tower of Pisa 7 735 5.5 711 Pisa Ghirlandina Tower 2 650 3.3 1 245 Modena Royal Palace 74 000 15 203 Caserta

Unit costs can differ depending on the size of the object Ghirlandina Tower, Modena Tower of Pisa Colosseum, Rome Royal Palace, Caserta

Typical maintenance/restoration activities identification and classification of every block units of the monument; biocide and anti fouling treatment; mechanical removal of deposits not pertinent to the original surfaces (black crusts, layers of lime, manure deposits of birds, resin and stucco fillings from previous restoration works, etc.); cleaning from the superficial deposits (sprinkled water, low pressure steam-jet, brushing, localized chemical cleaning, laser cleaning, etc.); repair of gaps in the walls and bonding of fragments; consolidation and protection of the stone structure.

Typical maintenance/restoration costs Treatment of stone facing under good conservation conditions: 70 €/m2 Treatment of stone facing under average conservation conditions: 170 €/m2 Treatment of stone facing under bad conservation conditions: 250 €/m2 Treatment of complex stone parts (i.e. balustrade): 600 €/m2 repair and integration of missing parts of the stone facing: 100 €/dm3

Typical maintenance/restoration costs Treatment of plasters under good conservation conditions: 60 €/m2 Treatment of plasters under average conservation conditions: 100 €/m2 Treatment of plasters under bad conservation conditions: 160 €/m2 Treatment of brickwork under good conservation conditions: 60 €/m2 Treatment of brickwork under average conservation conditions: 80 €/m2 Treatment of brickwork under bad conservation conditions: 170 €/m2 Restoration of wooden window frames: 270 €/m2 Restoration of gratings, railings and metal elements: 80 €/m2

Additional maintenance/restoration costs Technical costs related to the design, preliminary and support activities; Scaffolding (pipes and joints, worktop for scaffolding consisting of prefabricated metal tables, stair/elevator for scaffolding, dustproof shield, etc.); Loading, unloading and handling of materials; Transportation to a licensed authorized landfill of waste materials; Landfill charges; Security charges; Technical investigations such as thermographic investigations (16 €/m2) or magnetometric survey (25 €/m2).

Kf = Kt – Kb = M x P - M x P = M x P 1 - 1 Model for Calculating Costs due to Air Pollution REACH (Rationalised Economic Appraisal of Cultural Heritage) project Kf = Kt – Kb = M x P - M x P = M x P 1 - 1 tt tb tt tb Kt = total material corrosion costs per year Kb = material corrosion costs in the background atmosphere per year Kf = material corrosion costs due to air pollution per year M = stock of a given type of material at risk (m2) P = maintenance cost per square meter of the material Actual lifetime for the material (years) Lifetime in the background atmosphere (years) Limestone Corrosion depth before action: 100 mm Background corrosion rate: 3.2 mm per year Lifetime in the background atmosphere: 31.25 years

Actual lifetime vs recession rate (Limestone, corrosion depth before action: 100 mm)

Material corrosion costs due to air pollution (One-time maintenance work)

Thank you for your attention! Any questions?