Leak inside uPVC door

Hello all,

I've discovered a small leak at the bottom of a uPVC door. Here's a view of the inside (please excuse the state of the paintwork etc.:all part of the work in progress). Since taking up the carpet I've noticed a small but annoying amount of water collecting along the join between the frame and concrete threshold (marked with a red arrow) and also at the join between the two bits of the frame marked with a red arrow.



The water collects most of the way along those joins, not just where the arrowheads are. It's also presumably responsible for the tidemarks on the primed MDF skirting marked with the blue arrows. The tidemarks are on the bottom of the skirting on the left, but about halfway up on the right.

When I noticed the water collecting yesterday I opened the door and there was a small amount of moisture on the uPVC threshold. The underneath of the door was sopping wet, but there had been quite a lot of rain/snow so maybe that's normal

Here are a few more views.



Any ideas as to how to proceed?

Many thanks,

wrathkeg

Only a guess but I would suspect it may be running under the bottom rail where it is sitting on the concrete sill. Maybe try sealing along the bottom edge on the outside with sealant (use a paintable one so you can repaint the step) taking care not to block any drain holes that may be incorporated into the Alli frame.
The old red paint is forming a bit of a channel that may trap water.

Thanks. I think the join between the concrete sill and uPVC frame is already pretty well filled up with sealant, but I'll check next time I see it in daylight.

Yes, as I expected it all looks well sealed. The only bit that looks slightly questionable perhaps is right at one end, but I don't think that could explain the water pretty much along the length of the door and on the skirting at the other side.

A bit more information, as it's pouring down here. There is some moisture visible along the length of the topmost join shown with the red arrow on the first picture above. There is no sign of moisture (yet) on the lower join. I've opened the door to have a look at the sill, and there's a bit of water in there but not much.

There are a couple of concealed drains at the front (which don't show up on my pictures). I have put some water directly into those drains with a straw, and water comes out of the front of the frame and away onto the steps.

I am starting to wonder if, instead of running out the front, some of the water is running down the drains then back towards the house then seeping through that joint and also getting onto the skirting at each end. Is that possible? At the moment I can't think of any other way water is emerging there inside the house.

I also notice there are a couple of holes in the sill about two inches from each end (you can just make them out on my photos). I don't suppose that could be anything to do with it, could it? Getting desperate here...

Water does drain into the cill and there should be slots
for the water to weep out at the front ie. outside.
There shouldn't be random screw holes in the cill.

Yes, water is weeping out the front via the drains. I'll explore those screw holes a bit further. If water is getting through there, could that be finding it's way back into the house, or would it just seep through the front as from the drains?