You'll need to bring the plasterboard down. You can just cut out the blown section and replace the entire board. To make it good cover the joins with tape and skim over. Plasterer could do it in a half day for £150-£200
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You'll need to bring the plasterboard down. You can just cut out the blown section and replace the entire board. To make it good cover the joins with tape and skim over. Plasterer could do it in a half day for £150-£200