Moisture penetration appears on internal plaster sporadically, can be wet to the touch one day and dry the next or dry in the morning and wet in the evening.
Penetration does not appear directly after rainfall but I think may appear when external temperature is low and possibly in response to high heating levels internally.
Plaster affected is 12" high, 6" across and is triangular in shape with base at the bottom, above skirting. Plaster is damp above skirting but skirting appears unaffected. Floor level of skirting is two feet+ above external ground level due to cellar.
Patch is on the wall below the corner of bay window. External wall has filled hairline crack that damp patch could respond but filling the crack hasn't stopped moisture appearing
Any ideas of where damp is coming from? Penetration or rising?
thanks in advance
Mark
