2014 Bavaria C37 leaking window, maybe

[Asylum2.0]

Hello all,

My 2014 Cruiser 37 has off and on had a leak in the salon to port where I see water exit at the overhead cabinet at the forward end of the galley or the aft end of the salon.

This winter my boat did not get covered before the first snowfall and freeze.  I now have water further aft to the aft end of the galley cabinets.  I suspect the water is exiting further aft because the boat is blocked bow a bit up and the water is running further aft.

I have removed all but one of the access board in the cabinets and have found no sign of water. The acces panel that would allow inspection of the chainplate seems larger than the others and glued in place.  See pic.

I read an old thread about a leaky window.  I’d like to further inspect mine.

How do you remove the interior trim on the window? Didn’t want to pull too hard in the cold weather.
See pic

[tiger79]

I think the window trim will just pull off.  I haven't removed the trim on the big windows, but I have removed the trim on one of the hull portlights in the forecabin.

[Impavidus]

Asylum.

This is a known fault on the Bavaria.
The windows are beaded on a mastic sealant bead and the perimeter is filled. During this process Bavaria in their wisdom hold the window in position with a small block screwed into the moulding between that window and the next window. If you look from the outside you will see that there is a joint of mastic about 20-25mm wide between the two windows. This joint is obscured from view internally by the moulding in the centre right of your photo.
The problem arises because Bavaria do not back fill the gel coat from the screw hole with gel, they simply mastic over it. As the windows and the boat deck expand and contract at slightly different rates (one being dark acrylic and the other white GRP) the mastic is pulled in 3 directions.
If you check the technical data on the mastic you will see that this is a “No No!”  There should be a “Bond breaker” in the gap on top of the GRP. (And the hole should have been filled too!)
If you look carefully at this joint from the outside you will find that somewhere around the vertical joint, the mastic has de-laminated from the edge of the window. But It, still looks ok. Water gets through this gap and behind the vertical joint because that’s lost its grip too. The water then tracks down the inside and through the hole behind the pillar moulding in the ceiling where you can’t see it.
Carefully cut the mastic out at this vertical joint, clean the GRP and window edges toughly. Fill the hole in the GRP with gel coat. Put bond breaker tape in the gap over the GRP. Prime the edges of the window with the correct sealant primer (but not the bond breaker). Mask the widow edges and deck where the sealant should not go and prime these areas too. Apply the mastic sealant and trowel the surface flush with the window. 
The mastic will not bond properly if you do prime it or it is pulled in more than one plane.

Hope this helps.

Ant.

[Asylum2.0]

Ant,

Thanks for the response.  We have had quite a bit of rain the last couple of days.  Went to check on things.  The tarp I had over the area had moved and water was getting in.  Upon inspection I noticed the vertical joint as you describe looks as though the bead of silicone has separated from the glass.
I will temporarily apply some sealant externally when the weather warms a bit and test it with a hose.
In the meantime, I will keep it covered under plastic.
My plan was to clean up the area and reapply sealant.  Apparently, there is a bit more prep work before reapplying sealant.
I will take some before and after pictures.

[Impavidus]

No worries Asylum. there are some good sikaflex videos somewhere that explain how to use their product. May be worth a google.

Ant

[Asylum2.0]

Hello all,

I just wanted to give an update on the leak.
This spring has been very cool and I kept the winter cover on until two weeks ago to prevent water intrusion.
I first put some shrink wrap tape around the area I suspected and applied water from a hose all over the deck. No leak. 
Removed the tape and hosed off again. Water intrusion.  What’s amazing is the best I could tell, there was plenty of sealant but a razor slice thin separation where it meets the glass.  I removed a good portion of the rubberized sealant and the taped off my work area and applied new sealant.
Leak was gone.
I just launched the boat yesterday, so I am curious to see if the hull flexing in the travel lift straps can be a cause.

[Asylum2.0]

Hello all,

Well it seems Asylum2.0 is leaking again.  This time to port in the head and the salon cabinet just forward of the head.  After rain, the shower floor fills up with water and I've  traced it to above the cabinets.  My cabinet wood is starting to swell from the water.
I ran a hose on it today and duplicated the leak.  As I've gone through this before on the stbd side.  So I taped the window sealed with shrinkwrap tape and hosed it off again. You guessed it, no water intrusion.  I left the tape on as we will have heavy rains this evening.  I'll check back tomorrow.  If there is no water after tonight's rain, I'll cut away the tape on the vertical seam and hose off again.  That's where it leaked on the portside and it was an easy fix.  I'm hoping Bavaria is consistent.

I have noticed the black sealant used on the exterior at the glass/fiberglass washes out with just a wet rag.  Leaves black smudges all over the gelcoat.  Anyone ekese have this messy sealant?

[Yngmar]

I have noticed the black sealant used on the exterior at the glass/fiberglass washes out with just a wet rag.  Leaves black smudges all over the gelcoat.  Anyone ekese have this messy sealant?

That's consistent with UV light destroying the sealant. Common in high UV areas, especially with PU based sealants. Suggest resealing windows with a more UV stable product.

[Asylum2.0]

We didn’t get the rain forecasted the other night.  I cut out that black sealant between the two windows and made it to the gelcoat.  Just as Impavidus described I found the two holes.  See pictures.

I will seal them as described and fill the gap.  I used Boatlife black sealant last year and it has held up.  I’ve heard of a 100% Silicone product from GE.  It’s used by Glazers in high rise window installations.

We expect rain tomorrow evening, so that should give the sealant 24-36 hours to dry.  I left the shrink wrap tape on the rest of the window sealant.  IfI stay dry, I will remove the rest of the tape and hose test the windows.

I’m betting Bavaria is consistent with the leak problem.  I read years ago that Bavaria’s production facility is very automated.  I’m betting that automation will produce a consistent problem.

[Impavidus]

We didn’t get the rain forecasted the other night.  I cut out that black sealant between the two windows and made it to the gelcoat.  Just as Impavidus described I found the two holes.  See pictures.

I will seal them as described and fill the gap.  I used Boatlife black sealant last year and it has held up.  I’ve heard of a 100% Silicone product from GE.  It’s used by Glazers in high rise window installations.

We expect rain tomorrow evening, so that should give the sealant 24-36 hours to dry.  I left the shrink wrap tape on the rest of the window sealant.  IfI stay dry, I will remove the rest of the tape and hose test the windows.

I’m betting Bavaria is consistent with the leak problem.  I read years ago that Bavaria’s production facility is very automated.  I’m betting that automation will produce a consistent problem.

Glad you found the holes! Dont forget the bond breaker tape as descriped or your repair will be short lived. While typing, I am reminded that during the last winter in Spain we checked evry deck fitting and fixing on Impavidus. 4 of the 6 hatches had fixing screws that were lose. May be worth a look while you on deck with the tools. :-)

Sail Safe.
 Ant.

[Asylum2.0]

Thanks Ant,

I've been three weeks with no leaks.  My only question is, if the holes are how the water gets in, how does the water get behind the sealant?  When I cut out the old sealant, the lower hole was definitely weeping water.

[Impavidus]

Hi, The problem is that without the bond breaker the salant will let go at its weakest bond. This can be between the windows or even behind them. The water can then creep in.
The other thing to remember is in bad weather, with the wind howling there can be a pressure difference between the inside and outside of the boat. As the wind blows or sucks on the leeward side of the boat the water can be literally pumped in the smallest gap. It's a well known issue in cladding and facade design. (The pressures can be a lot. Modern buildings are tested to /+ 600 Pascals in most cases).
The bond breaker ensures that the seal back to the hull from the window is not compromised by allowing the joint only to be under stress in two directions not 3.

Hope that makes sense?

Best regards.

Ant.

[Salty]

Hi, The problem is that without the bond breaker the salant will let go at its weakest bond. This can be between the windows or even behind them. The water can then creep in.
The other thing to remember is in bad weather, with the wind howling there can be a pressure difference between the inside and outside of the boat. As the wind blows or sucks on the leeward side of the boat the water can be literally pumped in the smallest gap. It's a well known issue in cladding and facade design. (The pressures can be a lot. Modern buildings are tested to /+ 600 Pascals in most cases).
The bond breaker ensures that the seal back to the hull from the window is not compromised by allowing the joint only to be under stress in two directions not 3.

Hope that makes sense?

Best regards.

Ant.

It does indeed, thanks Ant.
Ok, my boat doesn’t have that kind of window fitting, but the pressures you describe were not something I had thought about, and suggest you have some kind of specialist knowledge in that area of building construction, but your point is very clear.

Every day, even us old gits, learn something new !