Emergency Works and Assessment
Emergency works and consents are two different avenues that are likely to come about when dealing with a property after a flood event. In some cases the flood damage responses by insurance companies, loss adjusters and contractors may be highly damaging to historic fabric and may breach listed building legislation.
Typical examples of the damage caused include the unauthorised and unnecessary removal and disposal of timber panelling or floors, and the removal of lime plaster. Wholesale removal of traditional materials is rarely ever justified when the materials can be salvaged and dried in situ. This not only ensures that historic fabric isn't lost but it also reduces the time and cost of completing stripping out and reinstatement.
Emergency work
Emergency works can be defined as 'work deemed as urgent, because they are of a structural or health and safety nature, or whereby not undertaking the works will result in further damage to the historic fabric.'
This does not mean that wholesale removal or stripping out can occur. Emergency works could involve the structural propping, sensitive removal, recording and reinstatement (where possible) by experienced professionals.
The local authority should be informed at the first opportunity of what emergency works have been undertaken and why. An agreed method must be in place prior to any removal or disposal. Stripping out might be justified due to structural damage, detachment of plaster or other similar situations and will likely require listed building consent.
Where removal is required to facilitate drying and prevent decay of the fabric, such as floor boards or timber panelling. As long as the material is carefully removed, recorded, stored and reinstated as original. This constitutes as emergency works and should be undertaken at the earliest point to ensure that decay to the fabric doesn't occur because it is left in standing water.
A great deal of damage can be caused to a listed building when those with little or no experience recommend undertaking works or the use or inappropriate materials. It is important to ensure that buildings of traditional construction are reinstated with materials that are able to respond to their environment for the benefit of the building and its occupants.
Whether the contractors or consultants are employed by the insurer or the person responsible for the building, it is important to ensure they have experience and knowledge of working on a listed building. This should include an understanding about what is important about the building's significance, and the legal ramifications where this is not considered.
Investigative and opening up works
It may be necessary to do investigative work that could mean opening up sections of the building to check for sources of moisture, the condition of the fabric, or to allow trapped moisture to evaporate. The process must be carefully targeted, planned and supervised to avoid the needless removal of perfectly viable original fabric.
Opening-up should not be allowed to develop into 'stripping out' - the wholesale removal of internal finishes (for which, in the case of a listed building, Listed Building Consent would be required before work began).
Stripping-out or opening-up work can be limited by non-destructive methods as well as by using infrared cameras, borescopes and moisture meters.
Before removing or dismantling any part of the structure make a visual record of it by means of a sketch, photograph or video. Make sure that items such as floorboards or pieces of joinery are numbered (in soft pencil on the reverse side) so that, if lifted temporarily, they can be put back in the same place, thus preserving the archaeological integrity of the building.
Structural issues
Signs of structural damage include:
- any new or progressive cracking
- leaning, tilting and subsidence of the structure that was not evident, or was not as pronounced, before the flood
- bulging or dislodged sections of the building caused by heavy impacts, or excessive pressure or undermined foundations
A structural engineer experienced in the conservation of historic buildings should be appointed to review any damage which may be structural and advise on remedial action. Emergency works such as temporary propping may be required to support the structure in the short term and prevent further damage or loss whilst a permanent repair is designed and detailed.
Once the immediate risk is removed, the local authority's conservation officer should be informed of these works to determine whether scheduled monument or listed building consent is required for the permanent repair.
Remove excess water
Before undertaking drying, repair or decontamination to a building it is important to remove any standing water, as the more water you extract, the less damage it can cause.
Removing excess water will depend on the surface and surrounding external environment. Where internal floor levels are higher and the flooring is hard, sweeping out excess water is a quick and simple method. However, this is not always possible and that is when mechanical systems might be needed such as pumping out water or using a wet vacuum.
A building with a basement is more at risk of structural failure where the pumping out of the water has not factored in the surrounding water table pressure on the external walls. Before deciding to pump water from a basement you first need to carry out a careful assessment of local drainage conditions outside and around the property. If the surrounding water level is high, pumping could increase the external pressure on foundation walls, which may cause fragile thin-walled structures to collapse inwards. Pumping before the floodwater has receded is pointless: as long as the groundwater table remains higher than the basement, water will continue to seep in through the walls until the groundwater level finds equilibrium.
Water damage can be divided into 'primary damage' and 'secondary damage'. Primary damage, such as expansion or shrinkage, staining, etc. is clearly evident. Secondary damage is the subsequent effects such as moisture travelling to areas that were not affected by the initial ingress. Preventing secondary damage is referred to as 'mitigation'.
Water trapped behind timber panelling can be removed fairly quickly with minimal damage by drilling tiny holes at the base.
Floorboards can buckle if they become saturated as a result of prolonged immersion in water. Removing a number of intermediate boards can help to allow some expansion without causing permanent damage to the boards and then the water in the voids can be easily pumped out.