Cat litter - bear with me here.....

I could try it @Sheal - I would have to start with fairly dry sand though, and goodness knows where I would get that at this time of year.

 

I used some hi-tech thick paint on the base of my Observatory to seal it off between it and the concrete floor. The paint will work even on damp and wet areas, sticking to the surface and drying within about 24 hours. You could use that to seal the base and other areas, inside or out, and you wouldn't have to wait for a dry period, and you could put on the flashing over the paint.

 

Its worth a shot @Sheal - I need to try and stem the flow first however. I am assuming that the flashing won't need things to be completely bone dry before application, as it sticks to brickwork etc. It's going to be fun working it around the ribs of the walls, especially down the side (the worst side) that buts up to the side of the greenhouse.

 

It's not cheap though, pete

 

Is that this stuff @ARMANDII?

Someone at work suggested that yesterday. I would apply it this weekend if I thought it would work, backing it up with the foam inside.

 

I'll just nip into the garage and have a look at the tin, FC.