Ultra soft denim radiant barrier and sound damper

[Radar]

I know that 'insulation' conversation has been beaten to death but I still have a question!  lol  I'm planning on using Ultra Soft Denim Radiant barrier in my van.  I've seen it used on youtube with the 'shiny' side directly against the van wall.  NO AIR GAP!  Doesn't this still require an air gap?  If I put the denim side against the interior wall with the 'shiny' side facing into the van, would the thickness of the denim (3/8" thick) be enough of an air gap?  The plan was to then add a layer of polyiso, then my wall.  

Any thoughts?  I've already ordered the Ultra Soft so please don't tell me not to use it!!!  lol


Thanks.

 

[Almost There]

I know that 'insulation' conversation has been beaten to death but I still have a question!  lol  I'm planning on using Ultra Soft Denim Radiant barrier in my van.  I've seen it used on youtube with the 'shiny' side directly against the van wall.  NO AIR GAP!  Doesn't this still require an air gap?  If I put the denim side against the interior wall with the 'shiny' side facing into the van, would the thickness of the denim (3/8" thick) be enough of an air gap?  The plan was to then add a layer of polyiso, then my wall.  

Any thoughts?  I've already ordered the Ultra Soft so please don't tell me not to use it!!!  lol


Thanks.

Any radiant heat barrier requires a dead air gap to work.

If you put the shiny side directly against the van wall, radiant heat will pass directly from the van body to the metallic coating on the 'insulation' product thereby defeating the whole purpose of installing a radiant heat barrier.

If you put the shiny side in, it will only act as a radiant heat barrier to protect from heat INSIDE the van.

Dead air is dead air, not a solid.

When installing a radiant heat barrier in conventional housing construction, one creates a dead air gap by stapling the RHB to the studs. Using it in a vehicle requires a little bit more ingenuity, hence the use of bubble wrap to create that needed dead air.

I'm curious as to why you chose this over Reflectix?

 

[ZoNiE]

I used 3" thick denim batts in my motorhome roof. Worked great. No shiny layer on it, but already had reflectix above it. The reflectix by itself was useless...

 

[TrainChaser]

Almost There:  "Any radiant heat barrier requires a dead air gap to work."

That appears to be an absolute.  People here advise the largest bubblepak you can find (not that thin stuff).  I have been looking online (Google Images) and see that practically everyone applies the radiant heat barrier (like Reflectix) directly to the walls and THEN apply 1x2" furring strips OVER that.  This does seems to be in conflict with what I'm reading (esp here).

And then I saw this photo, and this makes a lot more sense:  http://farm3.static.flickr.com/2643/3757418782_d11ddfef32.jpg

I don't see a way to affix the furring strips w/o screwing them into the metal, so you'll have to do some drilling of the metal (make sure you  know what you're doing, and WHERE); I would use self-tapping screws.

That material you're using looks very similar to indoor/outdoor carpeting in its semi-rigidity, so I'm thinking that you could just screw it to the furring strips (foil facing OUTWARD toward inner van skin) to create your dead-air space.

If you're getting the polyiso w/the foil, it seems that you could then install the foil side facing INWARD, and then cover it with your panelling.  That way, you would have the foil on the Ultra Touch facing out and the polyiso facing in, for benefit with heat and cold.

If I'm wrong here (I'm still learning), I'm sure someone will chime in!

 

[Radar]

Any radiant heat barrier requires a dead air gap to work.

If you put the shiny side directly against the van wall, radiant heat will pass directly from the van body to the metallic coating on the 'insulation' product thereby defeating the whole purpose of installing a radiant heat barrier.

If you put the shiny side in, it will only act as a radiant heat barrier to protect from heat INSIDE the van.

Dead air is dead air, not a solid.

When installing a radiant heat barrier in conventional housing construction, one creates a dead air gap by stapling the RHB to the studs. Using it in a vehicle requires a little bit more ingenuity, hence the use of bubble wrap to create that needed dead air.

I'm curious as to why you chose this over Reflectix?

I chose it over Reflectix because I was looking for something to attach directly to the interior van wall.  I thought this would do the trick.  But now I'm thinking that I may still need to maybe add reflectix to the inside of the paneling in order to create that Air Gap necessary to keep the outside heat from coming in.  Am I thinking correctly here?

 

[Not That Bob]

Reflectix is one of the most improperly used products I have ever seen.

If you want get any "R" value out of Reflectix it needs at-least 3/4" air gap with minimal contact with exterior and interior covering

Install 3/4 furring strip, staple then tape Reflectix,then another 3/4" furring strip add wall covering of your choice.

There are better choices.

 

[Almost There]

I chose it over Reflectix because I was looking for something to attach directly to the interior van wall.  I thought this would do the trick.  But now I'm thinking that I may still need to maybe add reflectix to the inside of the paneling in order to create that Air Gap necessary to keep the outside heat from coming in.  Am I thinking correctly here?

Reflectix won't give you an air gap, it REQUIRES an air gap to be effective.

I just went to the manufacturers' website for the Ultra Touch to see what it was. It's a denim product meant as a sound barrier (rated at .45 whatever that means), combined with a single layer of foil meant to be used as a radiant heat barrier. The website has no installation instructions on it but from what I know about radiant heat barriers (after much studying up on them...lol), you will definitely need a dead air gap between the foil and the van body for it to be effective as a radiant heat barrier.

The dead air gap MUST be between the source of the heat (the outside of the van) and the foil for it to be effective. Otherwise the heat of the sun on the van body will just pass right through the foil layer.

The Ultra Touch is meant to be installed the same way as Reflectix is - sealed around the edges with metal foil and a dead air gap between it and the vehicle body.

You don't need to use both Reflectix and the Ultra Touch, they are both meant to do the same job except the Ultra Touch also claims to have sound deadening qualities.

 

[TrainChaser]

'Radiant heat' for our purposes is sunlight. You only need Reflectix to cover the windows (over the dead-air space), as far as I've been able to discover.

Just plain heat passes through the sheet metal walls and roof. It just needs something dense enough to slow down or stop the heat, like Polyiso, which doesn't need the dead air space or the Reflectix.

 

[Almost There]

'Radiant heat' for our purposes is sunlight.  You only need Reflectix to cover the windows (over the dead-air space), as far as I've been able to discover.  

Just plain heat passes through the sheet metal walls and roof.  It just needs something dense enough to slow down or stop the heat, like Polyiso, which doesn't need the dead air space or the Reflectix.

And then it collects inside the vehicle raising the temperature to far above comfortable.

Stopping the heat entry works far better than 'slowing it down'.

Reflectix properly applied to the van metal walls does just that! As will the Ultra Touch although at a far higher cost than Reflectix because it is also meant as a sound barrier.

Polyiso is an insulation which is used to keep the heat in when living in colder weather and using a source of heat like a Mr. Heater.

Both have their place in protecting us from mother nature but neither are interchangeable.

For some of us protecting from radiant heat is all that's needed because we travel with the weather. Others will never need a radiant heat barrier but need all the insulation that they can find.

 

[Spaceman Spiff]

And then it collects inside the vehicle raising the temperature to far above comfortable.

Stopping the heat entry works far better than 'slowing it down'.

Reflectix properly applied to the van metal walls does just that! As will the Ultra Touch although at a far higher cost than Reflectix because it is also meant as a sound barrier.

Polyiso is an insulation which is used to keep the heat in when living in colder weather and using a source of heat like a Mr. Heater.

Both have their place in protecting us from mother nature but neither are interchangeable.

For some of us protecting from radiant heat is all that's needed because we travel with the weather. Others will never need a radiant heat barrier but need all the insulation that they can find.

TrainChaser is correct.

Reflectix works by reflecting the suns radiation back into the atmosphere, which is why it works well in windows.  When the sun heats a van body, Reflectix on the inside can only reflect back radiation from the van body to the van body, which absorbs some and radiates some (endless cycle here).  Once the van body's temperature is raised, all you can do is slow down the heat transfer to the interior air.  That is insulation's job and reflectix is a poor insulator (low R-value).  Once the van body is heated the air space between van and Reflectix is heated,  then the air trapped in the 'bubbles' is heated, then the van's interior is heated.

What Reflectix (and polyiso with foil skin) will do is keep the radiation from the van body from directly heating interior stuff.  But it won't stop the heat transfer from the van body, it just slows it down a little bit.

Insulation also keeps the cool in if you have AC or a swamp type cooler.  But unless you have something to pump heat in or pump heat out the air temperature inside the van will eventually equalize with the van body temperature.  The R-value of the insulation only determines how fast that happens.

I simplified a complex interaction but I hope it is clear, brain is mush this morning.

 -- Spiff

 

[TrainChaser]

"And then it collects inside the vehicle raising the temperature to far above comfortable.  Stopping the heat entry works far better than 'slowing it down'.

I think that that is more assumption than fact.  I have lived in vans with and without insulation.

Without the ability to seriously change the internal temperature (A/C or heater), the inside temperature will stabilize to match the outside temperature.  If it's freezing outside, it will eventually be freezing inside w/o a source of heat.  If it's 95F outside, it will eventually be 95F inside w/o a way to artificially cool it down.  With just bare-skin metal walls, the internal temp changes quickly; with insulation, the change comes more slowly, but it still comes.  You can surround a gallon of water in winter in ND with ten feet of insulation in all direction, but eventually, that water will freeze w/o a source of heat.  An open door will allow heat in.  Body heat can raise the temperature to a certain point (depending on the number of bodies).*

I'm not looking for perfection; I'm looking for a reasonably-priced way to be comfortable.  Weather is not as predictable as people like to think.  Many places are fine during the day and cool down quite a bit at night.

* Ten years ago, a couple in NM took 44 stranded motorists into their 1,200sf home during a snowstorm. [That's one piece of floor about 4x6ft per person if there was no furniture.]  I would bet that they didn't need any extra heat, and maybe even opened a few windows occasionally!  http://www.freerepublic.com/focus/f-chat/1761056/posts

 

[Not That Bob]

"If it's 95F outside, it will eventually be 95F inside", untrue.

If it is 95f out, I am assuming it is sunny.

The surface of the van will exceed the ambient air temperature.

Try touching a black hood on a sunny day (don't you will burn your hand)

With no insulation you have a rolling solar oven.

Ever hear the saying, "fry an egg on the sidewalk"?

You will not get the full benefit of the denim without complicating the build. How thick do you want your walls?

I would go poly against the outside surface and then your denim.