Flashing is the seal between two adjoining surfaces - such as the joint between a chimney stack and the roof. It can be a weak spot in the defences against damp. Slight movement of a house on its foundations can damage flashings, so regular checking is advisable.
Check for damage around the chimney stack, using binoculars if you don't have easy and safe access to the roof. If flashing has worked loose from the brickwork, dig out the old pointing and press the flashing tight into the gap, jamming it in place with wedges of lead.
If flashing has cracked or shows signs of deterioration, clean off any debris, prime with special flashing primer, then apply a strip of self adhesive flashing tape, pressing it well into place.• Examine other flashing around dormer windows or where extensions, garages or porches butt up against the house. Repair as above.
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