Windows and leaks

[PNWPederson]

I just purchased a 1970 Grand Banks and before I purchased her, the previous owner mentioned that they noticed a window leak on the starboard side in the v-berth, but only when they washed down. This window does not open. They also had the boat under cover. The boat has been surveyed twice in the last two years and come out each time shining. No water damage anywhere.

Since taking ownership of her, I have investigated this leak and the only thing that I could surmise was that the caulking was failing and/or missing. I put some Boat Life caulking around the window and waited for some rain. Oh boy, did we get some rain.

I live in the Pacific Northwest, specifically in Bellingham, and we have had an incredible weekend of wind and rain. Since last Friday, we have received almost 2" of rain and it was coming down sideways as the sustained winds were up to 20mph with gusts of 45mph. Sadly, as of now, I don't have covered storage and she was battered on the starboard side by the wind and rain.

Well, coming back down to the boat to see how she held up and I noticed that the v-berth leak was still there, but significantly slowed down, but then I noticed three other leaks in the main cabin, two below the window where the dinette is and another come from the valance above the window by the helm. This is all on the starboard side where the wind and rain was relentless. There wasn't a single leak on the port side.

I have checked all the weep holes by the windows and they are all clear. In fact, the window tracks/sills were all dry. I couldn't track down where the drips from the valance were coming from either. Frustrating.

When I brought the boat up from Seattle, I spent 11 hours on her. The owners had moved her to from her covered yacht club moorage to open moorage at Fisherman's Terminal. It had rained all night there, was raining when I left the dock and continued to rain for a few more hours. I was all over the boat looking her over and trying to find any issues I would need to address. The only leaking I found was the v-berth window.

Is it possible the leaks were happening because the wind was driving the rain up into the windows? From what I can see on the exterior, there is no way for water to get in around the windows unless it's the caulking. The paint is in good shape, for the most part. Any thoughts? Will I need to be removing the windows to reseal them?

 

[Comodave]

To do a proper caulking job you will have to remove the window and thoroughly clean all the old caulk off. Then wipe down with something like acetone. Then add new caulk as you reassemble it. Caulking on the outside almost never works well. It may work for a while but it will fail eventually.

Another way that I have fixed window leaks is to make covers out of Stamoid. Stamoid is waterproof, not water resistant. I put a metal keder strip across the top of the window and make it a bit wider than the window. Then make the cover large enough to cover the window and snap to the cabin side. On the top of the cover you sew a bolt rope on the Stamoid that slips into the keder track. Put the covers on if you are going to leave the boat or if it is raining. If you use white Stamoid and use the lighter weight you will still get a lot of light through the cover. Stamoid comes in 2 weights. The lighter weight will transmit more light. I made these covers for one of my boats that had teak window frames. I was afraid that I would break the frames if I removed them. The covers stopped the leaks.

 

[PNWPederson]

Another way that I have fixed window leaks is to make covers out of Stamoid. Stamoid is waterproof, not water resistant. I put a metal keder strip across the top of the window and make it a bit wider than the window. Then make the cover large enough to cover the window and snap to the cabin side. On the top of the cover you sew a bolt rope on the Stamoid that slips into the keder track. Put the covers on if you are going to leave the boat or if it is raining. If you use white Stamoid and use the lighter weight you will still get a lot of light through the cover. Stamoid comes in 2 weights. The lighter weight will transmit more light. I made these covers for one of my boats that had teak window frames. I was afraid that I would break the frames if I removed them. The covers stopped the leak

This is an interesting solution. Do you have any pictures of this?

 

[Comodave]

No, that was 12 boats and 20 years ago. Sailrite.com has all of the supplies.

 

[tiltrider1]

Everything is possible with leaks but it is more likely just wishful thinking. Tracing window leaks is not easy. Often the exit is far from the entrance.

My advice, invest in some clear vinyl and a big roll of preservation tape. Completely cover the window and wait for the next rain storm.

I had a rain leak show up in a port side interior light once. I covered the port windshield with vinyl and sealed it with preservation tape. Boat still leaked. Covered the center window. Still leaked. Covered the starboard window. Leak stopped. Uncovered the port and center window. Still no leak. Waited till spring and pulled the window. Found a hole in the frame.

 

[Choices]

I rebuilt all of my windows, not an easy job. No it one window at a time is doable but not efficient.

First make sure all drain holes work. Caulk window exterior all the way around.

Window covers help greatly. Sunbrella or phifortex screen really stop the water intrusion.

Go to my blog, grandbankschoices and you can see the process.

 

[SteveK]

I used lots of Captain Tolly on my GB. The window sill trough are wood, the track bleeds water into this trough, and these lead to the drain holes, actually over the edge of the plywood wall.
Sure when new and many years the original sealer worked. I would plug the drain at bottom and flood the trough with Captain Tolley. I put the boat for sale with no more leaks.

 

[RT Firefly]

Greetings,
Our first "big" boat was a well loved 1950, 34' Chris Craft Commander. The first year we had her, it was an extremely dry summer and we never thought about leakage, at all. Went out with friends with a 3 month old baby for Labour Day weekend and it POURED rain, in BUCKETS!!! We had every pot, pan, dish, container, tinfoil plates, coffee cups, buckets and bowls that was onboard under about 1/2 of the torrents flowing into that poor vessel. Wet, wet, wet! By the time we sold her 12 years later we had her pretty well water tight...almost. GREAT adventure when you're young (and foolish). Not so much when you're old (and foolish).

 

[Portage_Bay]

Where you are you will have many chances to find the leaks. I like the cover one window at a time to determine the leaker. Once found if you don't want to go to the effort to make the suggested stamoid covers there is a quick and dirty temporary fix to get you through the rainy season. Clear Gorilla Tape applied so it covers the glass to trim joint will work. A buddy used that, it lasted more than long enough to really and properly address the problem.

Do deal with it soon. Leaks that freeze only make things worse.

 

[Comodave]

It is simple to make the Stamoid covers. I can make one in less than a half hour. Maybe another half hour to install one.

 

[PNWPederson]

I appreciate all of the suggestions and help. With the systems of rain that will be coming through the PNW in the coming week, I think I'm going to try covering one window at a time to see if I can isolate the problem to help develop a repair plan. Ultimately, I will likely be removing each window and resealing them.

 

[tiltrider1]

Be very careful on your tape selection. Preservation tape is designed to seal to fiberglass and to release with minimum residual glue remaining. What does remain is designed to be easily cleaned up with alcohol. Not all tape is designed to release 6 months later.

It is not cheap but it’s worth it.

Amazon.com

 

[Portage_Bay]

Be very careful on your tape selection. Preservation tape is designed to seal to fiberglass and to release with minimum residual glue remaining. What does remain is designed to be easily cleaned up with alcohol. Not all tape is designed to release 6 months later.

It is not cheap but it’s worth it.

Amazon.com

Excellent points. I don't know what happened when my buddy removed through Gorilla tape

 

[RT Firefly]

Greetings,
Mr. P. What I would be tempted to do is tape ALL the windows now. The next time you will be expecting a stretch of NICE weather, take the tape off ONE window and do your leak/drench test on it. If that widow is good, do a second window and so on...
You mention upcoming wet weather. By taping ALL the windows now you should eliminate any leakage and further damage and can do your testing at YOUR leisure in nicer weather.
Just a thought...

 

[PNWPederson]

Greetings,
Mr. P. What I would be tempted to do is tape ALL the windows now. The next time you will be expecting a stretch of NICE weather, take the tape off ONE window and do your leak/drench test on it. If that widow is good, do a second window and so on...
You mention upcoming wet weather. By taping ALL the windows now you should eliminate any leakage and further damage and can do your testing at YOUR leisure in nicer weather.
Just a thought...

This is the route that I'll likely go with. Eventually I will remove and redo all the windows. I have a bottle of Captain Tolley's arriving today to help.

 

[PNWPederson]

I wanted to update on my windows as well as get some insight.

I have sealed the exterior of the windows with Boat Life white caulk. Additionally, prior to sealing with the caulk, I used Captain Tolley's Creeping Crack Cure to seal potential small cracks.

After sealing the windows, I covered the windows with plastic and taped around the plastic to the exterior of the window trim with preservation tape. I performed this task 1 1/2 weeks ago. I have covered all the windows on the starboard side (which catches all the wind and rain) as well as the v-berth window on the port side. I was unable to finish covering the cabin windows on the port side or aft due to commitments. All weep holes are clear. Here is what I'm seeing.

I do not see any issues with the cabin windows on the port or aft side. They are not covered, but I did seal them with caulk. There was very minor leaking prior to caulking.

The window in the head has stopped leaking. Win. The windows in the v-berth have significantly reduced the leaking, but haven't stopped completely. Here are photos of what I'm seeing in the v-berth.

This is the port side window in the v-berth

This is the starboard v-berth window

It's obvious that moisture is getting in around the screws, but from where? The channel above is dry and solid, no rot at all. I don't see anything externally that makes me believe there is an intrusion of a lot of water. All the water from both windows is coming from behind the trim.

The leaks in the port cabin windows have, for the most part, stopped. I've seen a couple of small lines on the walls, but nothing significant, especially considering the amount of rain we have received over the last month or so.

What is still an issue is the drip coming from the valence. It hasn't slowed down, but it's very puzzling. I can't tell where it might be coming from at all. The curtains, which sit up in the valences, are bone dry. The cockpit and seats on the flybridge are covered with canvas. I don't see any standing water on the flybridge. Last week while I was covering the windows, I did notice one of the scupper holes was clogged and I pulled out a bunch of screws and dirt and a lot of water came out. Since then, it seems dry and all is clear. Is the water coming from the cabin ceiling/flybridge deck? I would think that if it were, considering how much there is, the paneling covering the ceiling would show signs of moisture, which is does not. This one really has me perplexed and is my biggest problem.

I know and am planning on removing the windows this coming year to reseal them. That should fix any window leak issues. The valence leak is a whole other story. Any hints?

 

[Choices]

On most of these boats you have an exterior fiberglass shell. Maybe plywood sandwich between glass layers. The structure of the interior is bonded or screwed to this, and the finish paneling on top of that.

You still have a leak somewhere and it can be a long way off. Do you have handrails on cabin top? Have you looked under flying bridge dash area? What about front windshields?

You could dig the bungs out and pop that wood off to actually see where it is coming from. My guess the screws have penetrated something

I am not a fan of caulking the exterior when the entire frame could be in question from both sides and the tracks. It is just covering up the problem

At around that point on my boat it is almost exterior deck height. That would be my guess.

Port v berth window is not covered, correct? You need a fan with a heater to force air from inside to dry that woodwork out completely. What your seeing at bungs could just be from slowly drying out. Humidity is against you without heat.

 

[Comodave]

I wanted to update on my windows as well as get some insight.

I have sealed the exterior of the windows with Boat Life white caulk. Additionally, prior to sealing with the caulk, I used Captain Tolley's Creeping Crack Cure to seal potential small cracks.

After sealing the windows, I covered the windows with plastic and taped around the plastic to the exterior of the window trim with preservation tape. I performed this task 1 1/2 weeks ago. I have covered all the windows on the starboard side (which catches all the wind and rain) as well as the v-berth window on the port side. I was unable to finish covering the cabin windows on the port side or aft due to commitments. All weep holes are clear. Here is what I'm seeing.

I do not see any issues with the cabin windows on the port or aft side. They are not covered, but I did seal them with caulk. There was very minor leaking prior to caulking.

The window in the head has stopped leaking. Win. The windows in the v-berth have significantly reduced the leaking, but haven't stopped completely. Here are photos of what I'm seeing in the v-berth.

This is the port side window in the v-berth
View attachment 159905

This is the starboard v-berth window
View attachment 159906

It's obvious that moisture is getting in around the screws, but from where? The channel above is dry and solid, no rot at all. I don't see anything externally that makes me believe there is an intrusion of a lot of water. All the water from both windows is coming from behind the trim.

The leaks in the port cabin windows have, for the most part, stopped. I've seen a couple of small lines on the walls, but nothing significant, especially considering the amount of rain we have received over the last month or so.

What is still an issue is the drip coming from the valence. It hasn't slowed down, but it's very puzzling. I can't tell where it might be coming from at all. The curtains, which sit up in the valences, are bone dry. The cockpit and seats on the flybridge are covered with canvas. I don't see any standing water on the flybridge. Last week while I was covering the windows, I did notice one of the scupper holes was clogged and I pulled out a bunch of screws and dirt and a lot of water came out. Since then, it seems dry and all is clear. Is the water coming from the cabin ceiling/flybridge deck? I would think that if it were, considering how much there is, the paneling covering the ceiling would show signs of moisture, which is does not. This one really has me perplexed and is my biggest problem.

I know and am planning on removing the windows this coming year to reseal them. That should fix any window leak issues. The valence leak is a whole other story. Any hints?

First you need to do is remove the windows completely and clean up thoroughly. Then countersink the screw holes, this will allow some caulk to be around the screws to form an O ring around the screws. Clean everything again with acetone just before you assemble it.

Consider that you may also have a second source of leaking. Look above the windows everywhere for potential leaks. It is amazing how far water can travel before showing up inside.

 

[PNWPederson]

On most of these boats you have an exterior fiberglass shell. Maybe plywood sandwich between glass layers. The structure of the interior is bonded or screwed to this, and the finish paneling on top of that.

You still have a leak somewhere and it can be a long way off. Do you have handrails on cabin top? Have you looked under flying bridge dash area? What about front windshields?

You could dig the bungs out and pop that wood off to actually see where it is coming from. My guess the screws have penetrated something

I am not a fan of caulking the exterior when the entire frame could be in question from both sides and the tracks. It is just covering up the problem

At around that point on my boat it is almost exterior deck height. That would be my guess.

Port v berth window is not covered, correct? You need a fan with a heater to force air from inside to dry that woodwork out completely. What your seeing at bungs could just be from slowly drying out. Humidity is against you without heat.

I have a 1970 GB 32. The way I understand it, my cabin is a plywood cabin that is painted. The only fiberglass that I've been made aware of is the fiberglass for the flybridge deck/cabin ceiling.

The front windshields are totally dry. Haven't even sweated. I haven't checked under the flybridge dash as that is covered by canvas. The canvas goes from the windshield, over the dash and over the seating.

I do have handrails and I was wondering about those. I haven't noticed any bungs on the exterior of the handrails, so it seems they are secured from under, in the cabin ceiling space.

I realize that caulking is a stopgap in this instance, as is covering the windows with plastic. I want it to last until spring when I pull the boat for hull paint. That is when I'll start pulling windows and redoing them.

The v-berth windows are both covered with plastic. I am going to put a heater in the v-berth to dry out the windows. I was thinking that there could be some residual moisture coming out.

 

[PNWPederson]

First you need to do is remove the windows completely and clean up thoroughly. Then countersink the screw holes, this will allow some caulk to be around the screws to form an O ring around the screws. Clean everything again with acetone just before you assemble it.

Consider that you may also have a second source of leaking. Look above the windows everywhere for potential leaks. It is amazing how far water can travel before showing up inside.

I will be doing a complete overhaul of the windows starting in the spring. This includes pulling them and resealing them.

I have been looking everywhere for potential leaks. It's frustrating trying to search them out. I'll keep looking though.

 

[Leeward III]

Removing Grand Banks windows

 

[Choices]

Go to my blog, grandbankschoices, it shows rebuilding and rebedding my windows. Do it right and do it once

 

[SteveK]

OP is correct it is an all plywood boat and only the roof has a skin of fiberglass

I know and am planning on removing the windows this coming year to reseal them. That should fix any window leak issues. The valence leak is a whole other story. Any hints?

First I will repeat the success I had with Catain Tolly. It was not an apply once and done. For the windows I looked on exterior and any cracks found were first treated with Captain tully and then caulked.
For leaks below the window I would temporarily plug the drain hole and then flood the trough with Captain Tolly. Rinse and repeat until leaks stopped.
I did not have to remove windows or frames to end up with no leaks. Just had to seal the natural pathways of the plywood edge.

 

[GrandWood]

All the sliders on my boat leak, and have for sometime well before I purchased the boat, right now I just caulked um shut for the winter, forward head, aft head and aft cabin sliding windows are gonna come out in the spring. Fill the holes with marine plywood and install portholes. I’m old as dirt, I’ll be on this boat fulltime till I croak, then it’s my sons.

The big sliders in the saloon I’m removing and going to go with modern boat windows. All the plastic tracks are cracked and gone. Im sanding below all of the interior windows to wood, drying with electric heaters at present and soaking with penetrating epoxy. Next summer the entire house I’m taking to wood and soaking with penetrating epoxy. When I find rot, I dig it all out, soak with the epoxy and fill with epoxy fairing compound.
Has worked great with what I found this past summer.

1972 GB36, just plain plywood walls.

By the time im done it’s gonna be a plastic boat, lol