Cedar cladding water ingress

[Fezza]

Really hoping someone can offer me some advice regarding a problem I am having with some cedar cladding on a new build house.

 

It's a two storey house with the cladding mostly wrapped around the first floor of the exterior with rendered blockwork on the ground floor. 

 

When it rains, water is getting behind the cladding. It is running as opposed to condensation or general moisture. Looking up at the underside of the cladding, I can see that the batons are often soaked through, after a downpour. I've attached a couple of images. 

 

I really don't know where it is getting in and therefore how I can stop this. The cladding is tongue and groove and is secret fixed to 38mm batons through the tongue of the boards. The fixings used were stainless steel brads and a paslode nail gun was used. 

 

I've had several thoughts about how this might be happening and have tried to resolve these potential causes. Initially, I thought it might be running in between the top of the cladding and the soffit. But I've sealed this gap with compriband tape and also a sealant. 

 

Then I thought that it could be soaking through the boards. I treated it with Osmo undercoat and the UV oil which has made it very waterproof. 
 

My only final thoughts are that perhaps it could be running through the pin hole made from the brads - the boards have moved quite a lot so they might have opened up larger holes? Or the water is being blown up and over the tongue as water sits in the grooves and the problem is far worse when it's windy. 

 

Would be amazing if anyone has any ideas or knows what might be happening and any ideas of how to stop it. 

 

Thanks. 

[Declan52]

Take a pic of further back showing where the cladding meets the roof straight above the stains.

[Fezza]

2 minutes ago, Declan52 said:

Take a pic of further back showing where the cladding meets the roof straight above the stains.

Hi Declan,

 

Just taken these shots, hope they help....

[tonyshouse]

Is it tongue and grooved?  What is the length of your tongue and how far in does it go? Is it tongues up or grooves up? 
 

what is the bottom detail? 

[Fezza]

6 minutes ago, tonyshouse said:

Is it tongue and grooved?  What is the length of your tongue and how far in does it go? Is it tongues up or grooves up? 
 

what is the bottom detail? 

Hi Tony, 

 

Here is a drawing of the profile. 

[ProDave]

I would get up a ladder with a slow running hose pipe to see where it is getting in.  Starting above the staining above that window.

[Gone West]

Two of the vertical lines of stain appear to line up with the reveals of the first floor window.

[Declan52]

Was there weep vents put above the small window in the gable.

Could be leaking out of these down the wall and out.

Have you A ladder long enough to reach the roof directly above the window to see if there is a tile, felt or how the soffit is finished.

[Fezza]

3 hours ago, ProDave said:

I would get up a ladder with a slow running hose pipe to see where it is getting in.  Starting above the staining above that window.

Thanks, Dave. It's pretty wet at the minute but when it dries out, I'll have a go. 

[Fezza]

1 hour ago, PeterStarck said:

Two of the vertical lines of stain appear to line up with the reveals of the first floor window.

Thanks, Peter. I think there was some rain getting in at the bottom of the cheeks on the window reveal but I think I've stopped that. It's still happening elsewhere, away from the windows so it's a bit baffling. 

[Fezza]

47 minutes ago, Declan52 said:

Was there weep vents put above the small window in the gable.

Could be leaking out of these down the wall and out.

Have you A ladder long enough to reach the roof directly above the window to see if there is a tile, felt or how the soffit is finished.

I think there were weep vents put in there but even if it was leaking from there, there shouldn't be any rain getting into the cavity above the window. Also, it is happening in multiple places away from the windows.

 

I've been up there and had a good look at the roof line - there is nothing obvious. The felt looks like it is lapped over to prevent any water getting in under the tiles. The soffit is fixed to the timber frame - it's timber frame with a block skin. The blocks are then built up to the underside of the soffit. There is compriband tape sealing the gap between the cladding/blockwork and the soffit. 

 

 

[Declan52]

Have you a usb camera that you could use to have a look at different heights to trace where the waters route down the wall.

https://www.amazon.co.uk/Endoscope-Pancellent-Waterproof-Borescope-Inspection/dp/B01MR8EONS?ref_=mh_s9_apbd_orecs_b5bbP3H&pf_rd_r=ZJBB92NY4HEN5F5FYZQH&pf_rd_p=5a5edff1-715e-5f7d-8401-f9076d561d60&pf_rd_s=mobile-hybrid-11&pf_rd_t=BROWSE_ANYWHERE&pf_rd_i=5136303031

Not this particular one only using it as an example.

[coconutsaregood]

The rainscreen is just that, not a waterproof cladding. Capillary attraction will always allow water to travel through your cladding and the air allows for draining away. This is by design and not a defect is my understanding of the technology. If it was causing damp to the interior then that is a different issue and requires examination of the batten details. If it is staining that is an issue then that  is down to the choice of wood treatment in which there are numerous methods. I am sorry if I misunderstood your issue. I am not jealous you have a  new house.