We have extensive experience of general fabrication of a mild steel outer shell, with a number of internal liners. These multi-core fabrications are becoming very popular within the new green energy centres across the country. They can hold varying sizes and types of flue; allowing each liner to expand and contract as they are in use. These can be in excess of 50 meters, if required. Generally, they have an internal bolting arrangement, to leave a smooth finish on the outside of the windshield. Internal access or external access can be given to emissions test points, in line with M1 regulations.