Clear thermal window coverings

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TJM

Senior Member
Joined
May 31, 2013
Messages
490
Location
USA
Vessel Name
Harmony
Vessel Make
1982 41' President
We are year round liveaboards in CT. In the past years we have used the clear indoor shrink that you tape to the window frames and shrink with a heat gun. The problem is condensation gathers and saturates the wood windows. frames etc.... Our window frames are Aluminum and they get cold transferring the cold inside which yields condensation.
This year we want to place some clear thermal barrier "draft stoppers" on the outside of the windows. The outer frames are better sealed than the internal frames. The pieces eliminate the drafts from the sliding windows while adding an air cushion for insulation.

Has anybody else done this ? How did you secure the clear acrylic panels to the window frames or fiberglass ? We do not want velcro and a last resort would be a wooden frame. We were favoring snaps but ?
 
I would figure out how to fit nice exterior summer sun covers that snap in place.

Then have a set made with clear plastic winter windows sewn in.

Any overhang of the covers beyond the glass area might be padded out to make the outer covers fairly air tight. Wont match dual pane windows , but should be warmer.

You can of course still use the stick on plastic on the inside at the same time.
 
Try 3M window weather proofing on the Exterior of the window. We used this transparent film one winter cruise. ?I was also surprised it lasted for several years.
 
I have snaps around all the windows for summer sun covers.

For winter, I cut clear vinyl to the same shape as the sun covers and installed snaps directly on the vinyl.

I put these up when we lived on the boat in winter to reduce condensation. They work very well at keeping the windows clear. They also reduce the cold drafts and keep the interior warmer.

They lasted 17 years before they got scratched up and snaps started pulling out.
 
Thanks for all the tips. Struggling with cooling and heating issues, and appreciate the ideas!
 
We don't have the cold that you speak of, but to beat the heat, we add some extra interior insulation to the windows. Sailrite sells some clear adhesive snap studs that work perfect for mounting the insulation to the windows inside the window frame.
 
I have snaps around all the windows for summer sun covers.

For winter, I cut clear vinyl to the same shape as the sun covers and installed snaps directly on the vinyl.

That's a clever idea that I had not thought of.
 
I would figure out how to fit nice exterior summer sun covers that snap in place.

Then have a set made with clear plastic winter windows sewn in.

Any overhang of the covers beyond the glass area might be padded out to make the outer covers fairly air tight. Wont match dual pane windows , but should be warmer.

You can of course still use the stick on plastic on the inside at the same time.
That's a great idea. I had snap on heavy screens on my old boat, and a winter set as you describe would have been perfect.

To the OP: are you sure you need a second covering? My first liveaboard winter in Toronto last year I didn't make any initial efforts to seal up windows in part because I thought a bit of air exchange wouldn't be a bad thing and I could go at it if it was uncomfortably drafty. It never was, and I didn't have any condensation issues. Once under shrink wrap I didn't notice any drafts through the windows.

I'm settling in for another winter on a new-to-me boat and starting from scratch on winterizing. Probably my biggest concern is sealing things up too tight. But maybe that's just my taste. I've lived most of my winter life in old leaky houses.
 
We lived on the boat during an extra cold winter and the clear plastic sealed around the exterior well. The clear plastic I used was a heavier grade of vinyl window material that layed flat against the boat exterior. No condensation at all between the glass and the clear plastic.

A second sheet of plastic on the interior was not necessary.

I put the clear plastic on every fall and take them off in the spring. An added benefit of the clear window covers is no rain water in the tracks of opening windows. The water in the window tracks would turn into a green moss here in the PNW quickly.

Having a dehumidifier running in the boat, in addition to the window covers, will also reduce condensation, especially during cooking and showering.

To stop condensation from forming on the inside of the overhead hatch in the stateroom and dripping on the bed, I replace the bug screen with plastic in the cold season. I make the plastic cover out of plexiglass that is the same thickness as the bug screen frame. The frame of the bug screen is used as as a pattern to shape the plexiglass with a router. Foam weatherstripping around the perimeter of the plastic to reduce leaks.
 
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We're new. You liveaboard year round in CT? Don't you get snow and ice?
 
"We're new. You liveaboard year round in CT? Don't you get snow and ice?"

I lived aboard for decades in the NYC area.

Plenty of snow and ice , but snow is a delight as it adds insulation and cuts dock noise.

The hassle is when the slip freezes over , and the dock is using the dock water system to blow air . The bubbles make it sound like you are living in an aquarium .

The easy solution is to turn off the supply at your finger , but turn it back on as you leave the boat. Most time ashore is long enough to thin or remove the ice from lifting a pile, so no harm is done.

It is expensive to set up a boat for winter aboard the OAT can go into minus numbers F and stay for a week and in a severe storm electric can be off at a marina for a week.

Its only time and currency , and the lifestyle is worth it.
 
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I have snaps around all the windows for summer sun covers.

For winter, I cut clear vinyl to the same shape as the sun covers and installed snaps directly on the vinyl.

I put these up when we lived on the boat in winter to reduce condensation. They work very well at keeping the windows clear. They also reduce the cold drafts and keep the interior warmer.

They lasted 17 years before they got scratched up and snaps started pulling out.
This is a good idea. You can get the clear vinyl at Sailrite. While you're at it, get a snap installation tool. At $150, It's a pricy gizmo, but there isn't really a good alternative and I've used mine frequently to repair broken snaps.

https://www.sailrite.com/Pres-N-Sna...MI_JjU-YyE7AIVlYjICh2RIAK1EAQYASABEgKJrvD_BwE

Peter
 
Thanks for all the tips. Struggling with cooling and heating issues, and appreciate the ideas!

I was struggling with cooling issues and got a cheap FLIR camera.
It showed me a couple of areas I could insulate better
 
...."cheap FLIR camera."

Any recommendations on a cheap FLIR camera? Sounds like a fun gadget, but not something I would use enough to justify spending a lot of money on.
 
...."cheap FLIR camera."

Any recommendations on a cheap FLIR camera? Sounds like a fun gadget, but not something I would use enough to justify spending a lot of money on.

I know this was an old post I'm quoting... but this is a tool I use on my boat... understand it's not for everyone, but you can take photos and video with it and archive them if you're troubleshooting or are trying to solve a temperature problem.

https://www.globaltestsupply.com/pr...80634170069440&utm_content=FLIR - INSTRUMENTS
 
"Probably my biggest concern is sealing things up too tight."

Boats have a tiny interior volume compared to houses.

Just normal access with a door or companionway will be enough air changes .
 
I had to live aboard my boat while building my house. Winter in NC is not as cold as CT, but did get down in the 20's. Condensation inside the windows was horrible. Heat was iffy too due to reverse cycle units just not having enough grunt.

My fix was a dehumidifier. $200 from Lowes, completely solved the problem.
 
If your reverse cycle could not heat your boat perhaps their is something wrong with it. We live aboard full time just south of Annapolis. We have two identical 16,000 BTU units. One puts out heat of 45 degrees above ambient temp, the other just 7 degrees. It is being replaced next week. The likely culprit is a stuck reversing valve which cannot be replaced. Also, this unit cooled only marginally since we got the boat. By the way, the water temp today is 44 degrees. My good unit is effective down to 38 degrees as measured by my transducer. We have had condensation issues only occasionally. I have no idea why it doesn't occur frequently but am thankful. Now that I think about it, the condensation disappeared as the temps decreased.
I had to live aboard my boat while building my house. Winter in NC is not as cold as CT, but did get down in the 20's. Condensation inside the windows was horrible. Heat was iffy too due to reverse cycle units just not having enough grunt.

My fix was a dehumidifier. $200 from Lowes, completely solved the problem.
 
My units work fine, but with sea water at 35F, they just don't make much heat. And boat is not well insulated. Water temps up to 40F+, great heat. I just did not set up the boat for 20F living. Units do not have a freeze-up problem unless sea water flow is interrupted.

Get out of a hot shower and moisture all over the windows. Dehum was the ticket.
 
Yup, 35 degrees won't work. I'm hoping the water here stays at 40 or more. Last winter it did. By the way, Ski, thanks for the instruction you gave me on how to adjust the running speed on my Perkins 4.108 powered generator. It had been sagging to 57hz. Now it runs at 59.8hz with a 70% load on.
My units work fine, but with sea water at 35F, they just don't make much heat. And boat is not well insulated. Water temps up to 40F+, great heat. I just did not set up the boat for 20F living. Units do not have a freeze-up problem unless sea water flow is interrupted.

Get out of a hot shower and moisture all over the windows. Dehum was the ticket.
 
This will be our first winter aboard in the PNW. We have snaps for canvas covers, so I'd like to try making clear vinyl covers. What's the right thickness/gauge? Sailrite sells 12 - 60 gauge. Thanks!
 
This will be our first winter aboard in the PNW. We have snaps for canvas covers, so I'd like to try making clear vinyl covers. What's the right thickness/gauge? Sailrite sells 12 - 60 gauge. Thanks!

I'm not sure the gauge I used but you want it thick enough that it lays flat and also to retain the snaps.

You also want polished vinyl to make the exterior covering less visible.

If you plan to sew Sunbrella around the perimeter, then thickness of the vinyl is not as critical since the fabric on either side of the vinyl adds reinforcement to the snaps.

I don't sew fabric around the perimeter. I set the Press and Snap to install the snaps very tight to prevent snap pull out.

Depending on where in the PNW you live, there are several canvas suppliers around that supply clear vinyl. They are less expensive than Sailrite.

I buy from Rexx Pegg in Tacoma but they are wholesale only.
 
This will be our first winter aboard in the PNW. We have snaps for canvas covers, so I'd like to try making clear vinyl covers. What's the right thickness/gauge? Sailrite sells 12 - 60 gauge. Thanks!

I always wondered about clear coverings as a fuel saving measure.

I wonder just how much heating fuel one would save?
 
I always wondered about clear coverings as a fuel saving measure.

I wonder just how much heating fuel one would save?

I'm not sure if the clear plastic saves on fuel, due to the many air leaks on older boats.

I install them mostly to keep condensation from forming on the windows and to keep rainwater out of the window tracks, which prevents green stuff from growing in the track.

I do feel less cold emanating from the windows.

Insulating the hull also reduces cold and dehumidifiers reduce dampness.
 
I'm not sure if the clear plastic saves on fuel, due to the many air leaks on older boats.

I install them mostly to keep condensation from forming on the windows and to keep rainwater out of the window tracks, which prevents green stuff from growing in the track.

I do feel less cold emanating from the windows.

Insulating the hull also reduces cold and dehumidifiers reduce dampness.

Right now (and this is my last winter in a cold climate :) ) I just run the diesel furnaces and dehumidifiers set to 55%.

That seems to work but if there was a significant fuel savings I could in an afternoon sew up or even just cut clear vinyl and get some snaps set for exterior coverings.
 
I never considered that a clear vinyl could reduce heat loss... makes sense. I might consider that for my exterior saloon windows for the winter. Syjos's point about keeping the window tracts free of dirt, mold and mildew is a good one.


BTW Ender, you are in one of our favorite places to visit. We go to Poulsbo at least several weekends a year.
 
I never considered that a clear vinyl could reduce heat loss... makes sense. I might consider that for my exterior saloon windows for the winter. Syjos's point about keeping the window tracts free of dirt, mold and mildew is a good one.


BTW Ender, you are in one of our favorite places to visit. We go to Poulsbo at least several weekends a year.


The vinyl and the boats window glass sort of emulate double pane glass. The air trapped between the vinyl and glass is what reduce heat/cold conduction.
 
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Thanks, syjos. I'll look for clear vinyl locally (Poulsbo, Silverdale, Bremerton).


Yes, dhays, this is a beautiful place. It's nicely located for cruising up and down the sound, too. We've only been to Gig Harbor via car so far. One of these days we plan to get a Captain's Gig to replace our rollup dinghy.



Thanks,
Andy
 
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