T&T: Covers for the front windshield

[Steve Sipe]

Keith wrote:
> Sounds like you have Textilene now. White has the highest reflectance, so 
> would be best to help keep the boat cool, but also gets dirty very fast. It 
> doesn't really provide any insulation value however, although I've seen good 
> canvas folks make quilted covers that do that. My pilothouse has large flat 
> windows, so I got three sheets of that foam/foil home sheathing from Home 
> Depot and cut squares to press fit inside. These work great... the foil 
> reflects the heat and the foam insulates as well. I've measured temps on the 
> window sills of 130F without these, and 80F (where my AC is usually set) 
> with them in place. Cut my electric bill in half while in the marina.
>
>
> Keith
>   
Note that insulation applied outside the windows is much more effective 
than if applied inside, since the infrared radiation is blocked from 
entering the space far more effectively. Glass will allow it to pass, so 
reflective insulation applied inside the glass still allows much of the 
infrared energy to enter. The reflective screens you see inside car 
windshields really don't do a lot except bounce the infrared around 
inside the space.
I did the same on our previous boat, used insulation board behind the 
canvas windshield cover, what a difference it made!

Steve