OP
robsparky1975
i have had this before when heating installer done 4" core hole for boiler flue,when straight through 10mm earth cable,i crimped it together,i remember something similar asked in the niceic newsletter they recommend a box to conseal joint.the brb says all connections must have durable strength and continuity,one of which says the use of a compression tool is sufficent,i have cut and crimped onto existing water bonds to extend through to new gas supplyte when the route for new 10mm would be a real headache,it is acceptable to do so.