I have found the following contractor helpful, at least upto quotation stage ; they carried out a invasive boroscope survey and identified the Formaldehyde CWI has turned into one mass and was bridging the cavity and have quoted for its removal.

Maria Guercio

Customer Liaison Officer

Pro Point UKT – 0800 2404634  |  W – http://www.propoint-uk.co.uk

3 Y Graig Llantrisant CF72 8FB

Martyn Burnett