Reflectix Insulation (mylar silver bubble wrap)

[Jerry Bleeg]

After reading various posts regarding Reflectix vs. Foam insulation, I sent a email to Reflectix Inc. I told them what I was trying to do and they responded as below. It is interesting that they recommend a air space between the roof and reflectix material. My thoughts are to use 1/2" or 3/4" (if available) EPS glued to my headliner, then add my wires, then glue or tack the Reflectix to the EPS and roof spars. My thinking is I will end up with about 1/2" air space between the roof and the Reflectix as recommended. An added benefit would be the 1/2" EPS is easy to curve and attach to the headliner, and I would not have to notch or kerf it for wiring. I will probably just go with the Reflectix or EPS only in the hatch area. Depends on what I have left over after insulating the living area. Wud'u think? Read below.

Question: I am building a small camping trailer and am debating insulating it with EPS or your reflectictix product.
Can you tell me if you product would be appropriate to use in the roof of my trailer. I have a 1 1/2" gap in
my ceiling area that needs to be insulated. the general construction is like this from the outside to the
inside. .040 thickness Aluminum skin, 1/8" luan plywood, 1 1/2" air space (this is generally where EPS or
Fiberglass bat is added for insulation), 1/8" interior Ply ceiling panel. My hope is to keep the interior
warm at night and minimize solar heat gain during day times. My trailer has a overhead vent and side
windows for general ventilation. There will be no heater because it is so small that my own body heat
should be enough for most camping needs. I live and camp in California where the tempatures are
generally mild. Any advise you can give on using your product possibly in conjunction with 1" EPS would
be appreciated. I am trying to attain maximum R values and min. heat gains or losses. I have seen you
product at Home Depot.

Answer from Reflectix

Jerry,
The way for the Reflectix to provide benefit would be for you to install it with at least 1/2" airspace between the roof and the ceiling. If you wanted to add EPS, you would have the
roof, 1/2" air space, Reflectix, EPS, ceiling material.

Kindest Regards,
Tari Hendricks
Sales/Customer Service, ext.150
Reflectix, Inc. 800.879.3645

[Arne]

The air space creates a bit of a roof support problem, or it could. I used 1/8" ply for inside/outside roof, so did a foam fill to give the roof more support.

[bobhenry]

I looked at the polystyrene a bit differently. I saw it as a reinforcing member as well as insulation. For an example take a cardboard box and open the top and bottom flaps now fold it corner to corner as if you were going to store it. Now reopen the box and insert 2 layers of 1/2 foam near the center of the box and again try and fold it corner to corner. This reinforcement acts as an inserted shear panel that resists the racking of the wood members. A good snug fit is a rather inexpensive shear member that will stiffen up the wooden framing tremendiously.

[mikeschn]

Just think "resistance to convection". or is it "resistance to conduction"? Either word will work.

The objective is to keep the cold from conducting thru the roof of the teardrop, to the inside.

So take a piece of EPS, put a block of ice on one side, and put your hand on the other side. How long does it take before you can feel the ice thru the EPS.

Now take a piece of reflectix, and put a block of ice on one side and your hand on the other side. How long before you feel the ice thru the refletix?

If you can answer that question, you get an atta boy!!!

Mike...