I had just bought my sailboat and officially given possession of the keys. With a couple of good friends on board, and a 2 day motor sail ahead of us, we prepared to deliver the boat to her new home. That evening we packed the boat with our gear, and retired for the night with plans to head out early the next morning.
During that night a storm rolled in and and I quickly discovered that my ports leaked and that eventually I have to do something about it. We had to live with the dripping that weekend but once I was settled safely at my new home, I decided my first project would be replacing the leaky windows.

Unfortunately I had multiple leaks from two different issues. The first was the large “dead lights” in the main cabin. These large acrylic windows must have been the original windows that came with the boat as they had started to show hairline cracks and had hazy. The water however was coming in around the edges so my original plan was to just re-bed them in new sealant. Upon further investigation I realized that the plastic trim was brittle and would crack if I tried to pry it off the boat.

I did some research and found a company in California that had the original plans for the windows and ordered 4 brand new ones. I picked a smokey dark tint to it so people couldn’t look in. From inside they don’t seem tinted at all.

When they finally arrived, I started the messy process of removing the old ones. Starting from the inside I removed the plastic trim. A sharp putty knife or scraper, I worked around the edges of the window. It was hard work and had to switch to a screw driver and box cutter to get through the old sealant.

Once a window was removed, I started prepping the area for the new window. I should mention that I worked on one window at a time over a week, as it is a slow and messy process. One of the difficulties I faced was that I also lived aboard the boat. All the dust from sanding and scraping would fill the boat making a mess and problematic to live in. I did have to cover the window at one point with a garbage bag when the rain started later that week.

Looking at the area between the inside fiberglass skin and the exterior fiberglass you can see a gap. The areas along the top edge of the window was ply board that had been soggy for quite some time and started to rot. I painstakingly dug away at that soft pulp with a screwdriver and sucked it up with a shop vac. This was probably the slowest part of the whole job. Once I had cleaned out a nice clean groove, I filled that gap with epoxy that had been thickened up with colloidal silica beads. This prevented the epoxy from dripping down further.

Once the epoxy had cured I had a nice clean and strong windowsill to install the new window. The new windows were not a perfect fit. I had to sand the opening a bit to leave enough of a clearance for the contracting and expanding of the boat during the different seasons. I found the best way to do this was to get a sanding bit from home depot chucked into a drill. With one hand I sanded the opening wider, and with the other I held a shop vac to catch all the dust. Be sure to wear a face mask because this fiberglass and epoxy dust is toxic. I used west system epoxy as I had plenty of it at hand. Its not as strong smelling as polyester resin and I was more familiar using the mixing pumps.

I should also point out that the boat really did stink while the epoxy was curing and I didn’t think it was safe to sleep aboard for myself nor my cat. It was great having family to call on when needed.

Since the previous owner had tried to “fix” the leak previously by smearing silicone all around the ports outside trim, I had a lot of silicone to remove. The tricky thing with this is even if it looks like it was scraped off, the fiberglass still has oily traces of the silicone that will prevent future sealant from bonding. I spend many hours sanding and cleaning with acetone. I read sanding will rub it in further, but it was the only way that I could think of to work at the mess.

Working on the inside surface was more for cosmetic purposes. Using strong household cleaners, I removed water damage and stains to get a nice clean finish.

Once I had dry fit the window in place and spent enough time admiring it from inside and out, it was time to seal it to the boat. I did some research and decided on Boatlife Lifeseal in the end. I was given different advice from different people but the I think the only sure thing is that the 3m 5200 is way too strong and would be permanent. Lifeseal is white, holds well, has good flex, and I can still remove it in the future if needed. I wouldn’t use silicone as its strength is using it as a gasket, not as a “glue”.

Using a caulking gun, i applied liberal amounts to the inside lip of the window and carefully put the window in place. Here is where I messed up. The extra sealant oozed out and left large globs around the window. Thinking I could easily peel this off later, I left it to cure. It turns out it does not peel off easily at all! I think the pest strategy is to wipe off the excess right away and leave a nice finish.

I wish I had some photos of the caulking step.. There really isn’t that much to it though. You apply the goop all around the window edge and fit the window in being careful not to get goop all over the place. I couldn’t handle the camera and goop at the same time so no pictures of this step unfortunately.

I would recommend you clean up the extra goop at seeps out around the edges. I thought that if I let it be, that it would be easy to cut off once it had cured. Not So! It created a permanent mess all around the window edge. Even after I can painstakingly rubbed off the extra sealant, I noticed that over time dirt would stick to the fiberglass where the sealant had touched creating an ugly brown dirt ring around the window. So the lesson here is, clean that up right away!

One more photo of the new window from the inside looking out. You can see I have re-attached the inside trim to cover the gaps. The windows have ended up being leak free luckily. I did find other leaks however but thats another story. One other thing I should point up before wrapping this project up. When your buying your new windows, make sure your careful with your measurements. I had spoken a number of times with the window manufacturer to be sure I measured the hole properly.

These windows should last the boat another 10 to 15 years (I hope). If I had any plans to take this boat offshore then I wouldn’t recommend these. They are strong but a hearty ocean wave could probably destroy these windows eventually. The manufacturer also had the option of creating the windows out of glass but I chose not, to keep my costs down. I was keen on getting them made out of Lexan as they are the strongest material in the plastic window category. The manufacturer did convince me out of it saying that Lexan does haze and scratch much more easily than Acrylic. Time will tell how these windows hold out.