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I'm confused about what paint I can use on the bricks in my damp course.they have been painted years ago with a red masonry paint but look shabby now I havnt had any dampness in my bungalow but is there any paint I can use to smarten the look of my dpc without causing damp problems

My builder is connecting new wiring to existing circuit in the new extension for spots, switches, sockets, hob/Oven. He's used connectors and not running a new separate circuit because my circuit board has no space. Is this okay? Would I need a certificate for the new modifications from the builder?

New cartridge fitted, to shower mixer tap, water pressure fine and still a loud banging noise as shower is turned on, which can continue for about 15-20 seconds.