Best New Things Boat Project

Insulated Portlights: The Best New Thing In the Boat

Friday, November 21, 2014S.V. CAMBRIA

A couple of months ago, I started a series on the blog called “The Best New Thing In the Boat.”  Well, “series” might be a stretch since I’ve only written one other post, but you have to start somewhere.  And now that I’ve started, it’s time to build on it.

First, a little background.

We have a Sirus satellite radio on board and I used to listen to the Rachel Maddow Show on MSNBC almost every day (I’ve since been treated for my addiction and now it’s all Classic Vinyl or BB King Bluesville for me!).  Rachel does a segment from time to time called, “The Best New Thing In the World” where she introduces something new that’s caught her attention.  It can be a product, an idea or something somebody has done, and it was her segment that inspired me to start this “series”.  My first post was about our new portable freezer.  And while I have to admit that our second item isn’t as “sexy” or life-changing, it really is “The Best New Thing In the Boat” – window insulation! 

Winter has made its return and the entire country has been blasted with Arctic temperatures thanks to Typhoon Nuri out of Japan.   It’s been no different here in the Pacific Northwest and last week we experienced below freezing temperatures that left frost on the decks and the portlights dripping with condensation. 

For years, friends have been raving about window insulation.  You know the stuff – the kits they sell with double-sided tape and a plastic sheet that are supposed to seal out the cold air and keep things warmer.  But, for one reason or another, we hadn’t gotten around to trying it until last week and, I have to say, we’re impressed!

I was dubious at first and couldn’t see how a very light piece of plastic was going to keep all that dew at bay.  After all, when it comes to living-aboard during the winter months, we are Cambria’s biggest enemy.  But it does.  We still get some drops around the port rims from the cold (which are aluminum) and have to wipe them on occasion, but the windows themselves are dry as can be.  Even cooking, which used to steam up every portlight and hatch on the boat, is no longer an issue.  IF the plastic film gets foggy at all, it clears up in minutes. 

It’s still early days but both David and I are incredibly happy with the results:  The boat’s warmer, dryer and a lot more comfortable – all for under $10.

The Product:
There are several brands out there, but they’re all basically the same thing – a thin sheet of plastic they call “shrink” wrap (it doesn’t actually shrink) and heavy-duty double-sided tape.  We opted for the large window kit from Duck because that’s all that was on the shelf the day we finally remembered to look for it.  We had plenty of window film left over but ran short of tape.  We ended up purchasing a roll of Frost King which did the job but I found more difficult to work with than the Duck brand.  

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  1. Condensation on a live aboard boat can be a nightmare but it saves having to get a shower. Your idea may well be worth trying.
    The best thing we got aboard our boat was a seagull water filter meaning we can drink from the tanks no matter where we are. No more buying water and lugging plastic bottles around.

    1. We've got something similar aboard and I'm with you! Not because we don't have excellent water straight from the tap here (it tests better than bottled water) but because my husband has no qualms about filling the tanks with water from an untreated source (like a stream) -- anything to keep from running the water maker!

  2. Have not tried Duck Brand but I've had great results with 3M and Frost King over the last 15 years or so. Both of those brands BTW, do in fact shrink if you apply a little heat via a hair dryer or similar. It doesn't take much so be careful but the plastic will shrink and be clear and tight. Last batch we bought was while in New Zealand in 2013 as we were there until mid-July, the middle of their winter, and it got a bit frosty even on the North Island. We sailed down along the edge of the Roaring 40's and finally removed the film when we got to Rarotonga in the Cooks. BTW, I found you get more bang for the $$ by buying the "sliding door" kits as there's more plastic and tape for the dollar. Regardless, the material is highly recommended.

    Best of the season to you.

    S/V Silhouette

    1. Thanks for the tip, Silhouette! Since you can see through them perfectly well, I was thinking about keeping them on until it got too warm. Considering we're doing Alaska next season I reckon that'll be sometime in August . . . and then I can put more up in September. :)