Please help with cause of this mysterious leak!

There is usually a balconey cavity tray fitted uder that doorway, other ways I've seen it sealed is tanked with glassfibre over the aream then decking laid on top.

Tray is similar to one below.

 

Might not even have one.

This is what I mean by tanking with fibreglass, then you can laid your decking on top.

 

You cannot not fit cavity tray, now the place has been built, the only solution is tanking the balcony I would say.

And glassfibre is better than any paint on waterproofer in a tin, it's seamless, so no leaky joins.

Explorer Court Plymouth had glassfibre laid, then timber decking to finish.

http://polyroof.co.uk/explorer-court-plymouth/

 

One other question, the decking us it loose lay panel(s) or fixed down, if fixed are there bearers it sits on.
Is there any fall on the decking, & how does balcony drain?

 

I assume there is someone above you with a similar layout?

I would be tempted to open up a hole on the inside above floor level, it may be coming down the cavity and stopping at yours, if the wall is wet above floor level, then they need to investigate further up.

Also as a minor point
Is that guy actually on the outside on the ledge without a harness, and did they pile all the decking on the outside too, ready to fall on some unsuspecting passer by happily drinking their Christmas Costa

 

It's every bit as likely that the water is coming from above - coming in either around the roof, or the window. It can then travel where it bludy well wants to - water don't listen to no-one 'cept itsel'.

Why it's coming in only at floor level I cannot say - perhaps it's hitting a ridge, gap or seam there. But - although it may seem the obvious place to look - a puddle at floor level does not mean it's coming in at floor level.

I would suggest that they remove that interior window cill and have a gander down there...

(What's that bubbly stuff that's on the patio door cill? It looks hellish...)

 

would still check the wall above floor level, might be the answer you need!

 

Peeps, if the cill in Lee's forth photo (1st post) is removed, will that expose the cavity for a looksee?

http://community.screwfix.com/attachments/20151115_092209-jpg.10361/

 

Looking at photo's I am confused, 1st photo is this a end wall,why is is open, not blocked up, all that timber frame work needs to be removed & the area tanked.

How is he going to tank this, from photo, glass fibre tanking is the only solution in my opinion, far better than any bitumen tanking, as long the glass fibre are continued up further up the sides than the bedroom floor level & the finished decking, it will solve the problem.

 

Ideally the tanking need to finish above the laid decking a minimum of 150mm,even 200mm so it is above the finish floor level in the bedroom, this would prevent any water from the decking working it's way into the bedroom by volume of water during a heavy storm or by capillary action.

 

Hi
I see in your first pictures, one of the patio door cill,

Is that some sort of bubble wrap stuck to the sill?

My view is to investigate the cill detail.

Normally that part of the cill must be clear, and certainly not sealed in any way.

The gap at the bottom of door/and top of cill it to let water out.!
Like in effect weep holes

Check it out!

Regards
Peter