The National Waterproofing Group is made up of specialist contractors based around the country, offering coverage for all typ ... es of waterproofing and gas membrane installation services in their own areas. The group was formed by the contractors with a view to offering national coverage, with the resources of a national waterproofing company, but with the service of a local company. We work together to ensure each member maintains the high standards set out by the group. Whether you’re looking for structural or basement waterproofing, Gas membrane installation, damp control or timber treatment services, our surveyors are highly qualified and our technicians are expertly trained, holding nationally recognised qualifications. read more