CHTMAG.COM HISTORICAL CLEANING FEATURE PRESERVING HERITAGE AFTER FLOODS FEBRUARY 2016 19 CLEANING HYGIENE TODAY out fully. If this happens, then there can be serious structural failure. Thus, it is advisable to use expert technicians to dry out a building as they understand how much heat needs to be applied, at which part of a structure and for how long. In general terms, it is advisable to dry as slowly as possible. A damage management organisation will also have the right expertise to know how to monitor the rate of drying. The danger is that wood panelling and other materials could become too dry. However, what is ‘too dry’? This is a measurement that changes for every building. Technicians will understand the structural science of a building and what that means for their restoration programme. It is important for anyone carrying out work to find out if the building is listed and, if it is, what grade it has (1 or 2). If it is listed, then great care needs to be taken when removing anything. If a complicated piece of wall panelling needs to be removed, then this will need an expert eye making sure that listed-status rules are not contravened. Each piece of timber would need to be carefully dismantled, dried and then re-assembled in its original position. Also be aware that owners might not be fully conversant with what work can be legally carried out and will not have the power to allow you to undertake certain works anyway. structure, but also because of finishing materials and decorations. Plasterwork in many older properties is lime-based so it dries and hardens well after flooding. It can also aid in the drying operation because it allows the fabric beneath it to breathe. However, it may be a mistake to rip out plasterwork solely after carrying out a ‘knock test’ where the sound coming back indicates the wall is hollow. It may, in fact, be perfectly sound but is attached to timber battens. It may become unsafe though if moisture has affected the plaster dabs that hold a ceiling in place. Historic buildings often contain fixings made from bronze, brass, copper, silver and gold. In most cases, these metals will not be damaged by one immersion so long as they are allowed to dry quickly. Problems can occur though if soaked timber is attached with nails or screws. These can start to rust if the surrounding woodwork is not dried the damage becomes worse the longer it takes to begin remedial drying”
CHT February 2016
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