Two steps forward, one step back..

That old addage rang true today when, just in time, we noticed water leaking in over and aroundcthe head of the living room window. At first it seemed like the expanding foam seal around the perimeter of the window had failed. But then we realised the water, after heavy rain and wind last night, was coming from above the head of the window internally. So we set about finding out how....got the hose pipe out and sprayed water externally just above the head of the window. To our shock we found the water was soaking straight through the external membrane and heading down and dripping onto the window head!
So, we had to strip back and replace the membrane. More rain this evening so hopefully the job is done and we can get back on track with the cladding tomorrow...