If buying foil faced insulation, does the foil go toward the outside wall or toward the interior of the trailer?  Is the foil itself the vapor barrier or does something else need to be added?  I've read conflicting opinions. 

Other choices for insulation would be............?

Flexible foam sheeting (is that the pink stuff in the big box stores),

aluminized Heat and Sound Insulation Shield. 

Anything else? 

Do I need to worry about a vapor barrier with those and if so, what do you recommend?

Thanks so much,

Kim Huck

I've read thru the posts about dressing room insulation but I need some clarification please.  I know this topic has been discussed before but for the life of me, I can't seem to find the answers to the following questions.  I must not be using the correct search words. 

First, if using foil faced insulation, does the foil go toward the outside wall or toward the interior of the trailer?  Is the foil itself the vapor barrier or does something else need to be added like firring (sp?) strips and if so, do the firring strips go against the wall first and then the insulation or the other way around? 

Second, I've seen flexible foam sheeting and aluminized heat and sound insulation shield also recommended as insulation choices.  Do the same principles apply to those regarding vapor barrier and/or firring strips.

Third, are there any other proven choices for insulation? 

Thanks so much,

Kim Huck

Vapor barrier in a horse trailer doesn't have a lot of effect.  The space inside the trailer vs the size of the door and windows means the humidity is going to be pretty much the same inside as outside.  If you boil a lot of water or take a lot of showers, You might increase the humidity level to something higher than the outside air.  But for most trailers it's a mute point.

Insulation deal with 3 types of heat transfer,

1st. Conduction where heat passes thru conductive material.   Heat will travel thru solid objects like Aluminum studs faster than it will travel thru dead air.  Insulations is usually of lower density material ( foam, fiberglass, rock wool) to slow the thermal transfer.

2nd Convection where air movements carry heat.  Air trapped in a confined space will move in a convection circle.  It asorbs heat from the warm wall and rises, as it looses heat on the opposite wall it will drop.  This circle of moving air moves more heat than dead air.  Insulation is supposed to restrict or stop the movements of the air in a cavity. This is way bubble wrap makes good insulation, It traps the air in small bubbles.

Radiation where the heat radiates.  This like feeling the heat from the sun or a fire. It radiates away from the source and you feel it when it strikes you. Foil is good at reflecting the radiated heat back toward it's source.  So you want to place the foil on the side of the wall that you want to prevent the radiation from passing thru.  If you are in a cold climate and trying to retain heat. You would want the foil on the inside.  In a hot climate you would want the foil facing out to prevent the heat from entering.

Thank you so much for your helpful knowledge.  You guys rock!

Kim

The foil face is faced towards whatever side you want to reflect the heat. If your primary concern is for internal LQ heating, the foil is faced inward. If your concerns are oppressive sunlight and hot trailer skin temperatures, the foil is placed outward.

The easiest way to handle both installations, is to purchase foil faced insulation with the reflective membranes on both sides.