Reflectix Over Windows

[mitchk-SKO]

Hey all, I "finished" my short bus build a couple of months ago and have been traveling the US. I am currently in Colorado, which is where I will be for the rest of the winter. I have a 5kw diesel heater which has been working out great but I'm wondering if I should continue to try and improve the insulation of the bus. I know people have different opinions about reflectix but do yall think it would be beneficial for my windows? I have curtains so the reflectix would be a barrier between the curtains and the windows.

Side note, and this may be a dumb question.... If it is very sunny outside I can maintain 50 to 65 degrees in the bus with no heater even if the temp is around freezing. Would reflectix actually hurt in this situation because it would reflect the warming sunlight?

 

[novice-SKO]

I think just about everyone here will tell you insulation is of the utmost.



Your diesel heater will do more to warm the bus than the sunshine, and you should definitely put Reflectix in your window to keep that diesel heat inside as much as possible. When I put it in the windows of my Geo this summer on a cross country road trip, it still got hot in the afternoons from the sunshine. I didn't have an air gap, unless all the empty space inside my car counts.



Curtains paired with it are sure to improve the insulative properties as well, even if not by much. Hope you're able to stay warm!

 

[Danjo-SKO]

A way to make it even more insulative is to use it to block infiltration. If you use the continuous roll and have it closed at the top and bottom of your window, it will go a long way toward keeping cold air from leaking in through the windows.

There’s another route to go; window insulation Mylar film. It’s applied with double sided tape and pulled tight with a hair dyer. When done well it’s hard to see. Still let’s light and sunshine in, blocks conduction and convection currents and well as air infiltration. You can find it at your local hardware store where they have weatherstripping. You may be able to find it in long rolls. I just bought a roll 25 feet long by 80 inches wide.

 

[mitchk-SKO]

I think just about everyone here will tell you insulation is of the utmost.



Your diesel heater will do more to warm the bus than the sunshine, and you should definitely put Reflectix in your window to keep that diesel heat inside as much as possible. When I put it in the windows of my Geo this summer on a cross country road trip, it still got hot in the afternoons from the sunshine. I didn't have an air gap, unless all the empty space inside my car counts.



Curtains paired with it are sure to improve the insulative properties as well, even if not by much. Hope you're able to stay warm!

Hey thanks for the reply! I agree that insulation was important and I have insulated everything but the windows with 1.5" XPS insulation. However, I have heard a lot of negative reviews about the reflectix so I wanted to make sure it was even worth using!

I don't use the diesel heater much/ at all during the day because like I said I can keep a decent temp with just sunlight. But I guess I could just remove the reflectix during the day and put it back up during the night when I run the heaters. Unless I am wrong assuming that the reflectix would actually be worse during the day if I am heating the bus purely by sunlight.

 

[mitchk-SKO]

A way to make it even more insulative is to use it to block infiltration. If you use the continuous roll and have it closed at the top and bottom of your window, it will go a long way toward keeping cold air from leaking in through the windows.

There’s another route to go; window insulation Mylar film. It’s applied with double sided tape and pulled tight with a hair dyer. When done well it’s hard to see. Still let’s light and sunshine in, blocks conduction and convection currents and well as air infiltration. You can find it at your local hardware store where they have weatherstripping. You may be able to find it in long rolls. I just bought a roll 25 feet long by 80 inches wide.

Interesting, I will definitely have to check that out. Mylar film might be the way to go...

 

[Danjo-SKO]

Interesting, I will definitely have to check that out. Mylar film might be the way to go...

I’ve used it in my apartment for years. Just to give you an idea of its effectiveness, I have a 30K BTU heater and 3 big 5x5 windows that leak really bad. I’ve tried weatherstripping with little effect. With the heater blasting, half the room is hot, but the other half near the windows if super chilly. With the Mylar on the windows, the place warms up quickly and evenly.

It’s worth 25 bucks to try it. I think you’ll love it.

 

[Native-SKO]

With respect to Reflectix ... here is a real-world example.


Our bus is stock insulation with three coats tof elastomeric paint on the roof (with ceramic beads in each coat). The ouside up to the drip rails are primed with flat black. With nothing on the windows, you can feel the heat from the sun ... in the summer and winter.


While taking trips of household goods, we hung Reflectix from a guy wire above the electrical channel which is above the windows. The Reflectix is full width and runs all the way down the sides for 25 feet. This little bit of Reflectix heeps the sun from heating up the bus as much as it did without. It also keeps the interior warmer once it is warmed up.


So, if you want the solar heating system (i.e. the sun) to do its job, you would want to remove the Reflectix from the windows in the sun to provide that solar heating ... and replace the Reflectix once the sun is no longer shining on them. However, you will probably be happy with keeping all of the windows covered and running the heater whenever you need a little more heat.