The Provision of Cavity Wall Insulation Extraction for Caerphilly CBC

Descriptions

Caerphilly County Borough Council is seeking expressions of interest from organisations that are able to provide a specialist service for the extraction of cavity wall insulation.The contractor will be required to undertake the extraction of any form of failed cavity wall insulation with minimum disruption to the structure or aesthetics of the building.The Contractor is to carry out a pre-extraction inspection with a borescope or a similar piece of equipment to establish what insulation type is in the cavity e.g. loose bead fill, bonded fill or fibre fill with the results recorded on a pre-extraction certificate.Any internal damage to properties is to be recorded photographically as part of this inspection and included with the pre extraction paperworkCavity Wall Insulation extraction involving flues, chimneys and combustion air ventilators installed in the property shall not commence until the pre-extraction check and appropriate certification is in place. A copy of this certificate is to be included with the job documentation and forwarded to the Authority.Removal of insulation will be to all property elevations and is required on all flats and two story dwellings.Following identification of insulation type, the material can then be extracted. The extraction method used shall employ a Pneumatic whip and air extraction unit to break up and extract the cavity wall insulation.The contractor is required to clear the cavity to a minimum of 100mm below Damp Proof Cause (DPC) level depending on the type of property and means of construction.If the insulation cannot be extracted e.g. if it is too wet, then the appropriate amount of brickwork will have to be removed in strategic positions to allow for physical removal with rods or similar.Where the above method is required, an allowance will need to be made for access equipment e.g. tower scaffold etc. If access equipment is to be used, all necessary Health and Safety precautions are to taken with particular attention given to the customer and continuous access.Where brickwork is removed and the cavity is exposed, an inspection will need to be done either manually or with the borescope to search for any bridging of the cavity from remaining insulation or rubble e.g. at DPC level, over door and window openings and at boiler flues and fan ducting openings.All brickwork and wall tiles removed for access to the cavity is to be replaced using existing bricks if possible. If this is not possible, the closest match of texture and colour is to be achieved, and re-pointed to match existing. Care needs to be taken not to bridge the cavity whilst making good.As part of the work, a single terracotta brick vent measuring 215 x 65mm is to be installed central of the elevation on the second course above DPC level. It is only to continue into cavity area, not through to internal skin. This is to be incorporated on all rear elevations and south facing side elevation walls. All making good is to be carried out above.Each elevation will need to be inspected via borescope on completion to ensure that the cavity is free from any insulation and rubble thus avoiding any further bridging allowing the transfer of water across the cavity.On completion of the extraction a post extraction check is to be carried out and if successful a post extraction certificate issued. A copy of this certificate is to be included with the job documentation and supported by photographic and/or video evidence and forwarded to the Authority.If your organisation is able to undertake the works as detailed above then please respond to thomaj11@caerphilly.gov.uk by Tuesday 19 April 2016 at 12 noon proving a brief explanation of what your organisation can offer and any alternative methods of extraction the Authority can consider. Any alternative method is required to cause minimum damage and only create small holes.NOTE: To register your interest in this notice and obtain any additional information please visit the Sell2Wales Web Site at http://www.sell2wales.gov.wales/Search/Search_Switch.aspx?ID=43172.