I have patio doors leading to my garden from my lounge. The doors were installed directly onto brickwork but there is no evidence of a damp proof course between the brickwork and the skirting board under the patio door. The brick work itself feels damp. This brickwork bridges the gap between the two cavity walls either side of the doors. I wonder if this is normal? Do i need to be worried?
There should be a vertical DPC to stop water getting from the outside skin of the wall to the inside skin Guy. This is usually inserted either side of the door where the skins return to meet each other and close the cavity. There is no point putting a horizontal DPC under the plastic cill of the door as a DPC is there to stop water being soaked up by an adjacent surface. PVC does not soak up water! There should certainly be something impervious between the external brickwork and the internal walls wahatever the situation as there is no way the inside walls should be allowed to get damp.