Cant find cause of leak under balcony

[Simba_ali]

Hello,

Another winter ... different leak! This one is a different room directly underneath the edge of a balcony where the the rail is.

I've pulled some of the decking up and tested all the seams and the areas in the photos with a hairdryer to create wind and cannot make it leak.

It either requires hours and hours of wind driven rain to show up or i am missing something...

I've attached some photos, the sealant around the post and the couple of holes Ive tested with water. Nothing shows up. .any clues?

Cheers

 

[CBW]

Have you tested around the decking area?

 

[Simba_ali]

Have you tested around the decking area?

Well in normal heavy rain the leak doesn't show. Only in South Westerly high winds and rain.

My original thought was the railing must be screwed Into the structure which would break any waterproof membrane. If sealant is missing maybe water is getting blown in that way.

Surely the railing posts would be sealed with Abit more that just this sealant though??

 

[datarebal]

There's a spilt in the single ply. obliviously it'll leak

 

[Simba_ali]

There's a spilt in the single ply. obliviously it'll leak

So you think that split is big enough for that stain?

 

[datarebal]

Of course

 

[Simba_ali]

Of course

Abit simplistic... considering I've tried to make this area leak already.

 

[freddiemercurystwin]

Water always finds a way, just because you can't make it leak on demand does not mean it's not leaking, the evidence is there. Could it be condensation forming in the ceiling void, that can be an issue with balconies above habitable rooms.

 

[JohnD]

How does the water under that horrible decking drain away?

 

[datarebal]

Abit simplistic... considering I've tried to make this area leak already.

Maybe get a single ply specialist to fix it properly

 

[Simba_ali]

Water always finds a way, just because you can't make it leak on demand does not mean it's not leaking, the evidence is there. Could it be condensation forming in the ceiling void, that can be an issue with balconies above habitable rooms.

I doubt it's condensation not sure though, Im leaning towards filling all gaps visible and seeing what happens.

 

[freddiemercurystwin]

A leak is the most pobably cause, though if warm air containing moisture gets into the space beneath the deck immediately under the membrane where can that moisture go when it condensates?

 

[Simba_ali]

A leak is the most pobably cause, though if warm air containing moisture gets into the space beneath the deck immediately under the membrane where can that moisture go when it condensates?

A very good point, but the building is fairly new and nothing has shown up until the last few weeks. Wouldnt condensation of been present from day 1?

The fact there is a hole in the corner (even if it is small) and it's only 10-20cm from the location of the leak cannot just be coincidence...or that's what I keep trying to convince myself.

It's because i couldn't make it leak at the hole location that I keep thinking of other possibilities. Maybe my air dryer doesn't match winter wind power!

 

[JohnD]

Maybe try a garden sprayer.

 

[freddiemercurystwin]

If you suspect that split, which seems reasonable, then stick some thick plastic or something over it and the surrounding are so that it cannot get wet, then see if your leak recurs in the next few weeks/months. That will eliminate it. I've seen commercial roofers messing about with hoses, sprayers, al-sorts trying to find leaks in flat roofs without success but they cannot replicate the way rain/wind/nature behaves and make the roof leak.