Ever heard of spraying insulation with a home d rental?

[wopachop]

Pretty sure home depot still rents those insulation blowers. Not the liquid can stuff but actual fluffy material you spray into an attic or wall space.

My friends 2002 weekend warrior stays so much cooler than my 16 Stealth. My ceiling has 2" thick material laying up there. In prior summers i thought spraying some insulation in there would be rather easy. Worse case its too heavy and pops some panels.

I remember reading Mex talk about putting really thick foam board directly onto his ceiling. Thats an option. I have 1" foam in my windows.

Any ideas for adding insulation that does not include removing the ceiling panels?

[free_radical]

How about painting the roof with insulating paint

https://youtu.be/Ery8WXAs7tE

[rexlion]

That fluffy insulation will settle after while in an attic. Imagine how it will settle when you shake it for a few hundred miles. I think it would absorb moisture over time and flatten even more.

A pro might be able to spray icynene foam up there. Not certain. Actually, polyurethane would be a better foam since it's closed-cell and can't absorb water (icynene is open-cell), but I suspect the polyurethane expansion would risk breaking the ceiling.

I personally don't think the air space provides as much "thermal break" value as insulated space would.

[Gdetrailer]

Ceiling may have 5" in the center, but that tapers down to near zero at the edges.

The roof trusses have a taper, and typically will give you 5" in the center but they taper down to less than 2" at the ends. Your talking 8ft long trusses and only about 2 ft near the center you might be able to stuff some insulation in.

The there is an issue of lack of air space above the insulation, pack the insulation against the roof and you no longer have valuable air gap between the roof and insulation. Removing that gap will allow easier thermal transfer of the heat from the roof into the insulation and then to your interior space. That air gap above is intentional for a reason.

Your going to go through a lot of hassle for maybe R1-R2 increase average on the entire roof. Very little gain for a lot of hard work and hassle, you will never notice R1 or R2 increase.

If you really want more roof insulation, go big or go home is the way to go, create a 2x4 false ceiling not touching the existing ceiling then fill the false ceiling with 3" worth of poly Iso, leave an 1/4" air gap between each layer and the existing ceiling.. Each 1" thick poly Iso gives you R6 so you get R18 plus each air gap between the boards will give additional couple of R values..

Say you have three air gaps you get an additional R6 out of 1/4" air gaps giving you for a total of R24 increase.

[wopachop]

I know what you mean about keeping insulation fluffy and not compressed. Ive installed a decent amount. Hate the stuff.

My walls are solid foam. The ceiling has lots of open space. Its maybe 5" thick and only has a little 2" flap of insulation laying on top. Thought i could spray additional insulation above the existing. Keep it fluffy and loose. Would have to reduce down the hose diameter.

Shoot....with all the existing speaker holes and ceiling vents. I could almost stuff insulation in there by hand. Cant really hurt. Wont be able to access every bay but thats ok. I could stuff a few handfuls in. Then push it back gently with a pole.

[BarabooBob]

Menards sells a product called Froth-Pak. It is a two part product that requires a spray gun to install it. The product with spray gun sells for over $850 and covers 65- sq ft at 1" thick. I don't think you can put into an enclosed wall.

[Gdetrailer]

wopachop wrote:

Any ideas for adding insulation that does not include removing the ceiling panels?

Insulation does not work that way, you cannot just pile up more and expect to improve the R value when there is no additional space for the insulation.

Fiberglas and blown in insulation depend on trapped air pockets within the insulation, compressing these types of insulation results in the opposite effect, much less R value.

Basically there is nothing you can do to improve the R value of what you have unless you are willing to either lose inside space by adding additional wall studs on the inside or adding to the outside and then add high performance Polyisocyanurate foam which has a R6 insulation value per inch of thickness.

Spray foams are a bit more effective than the solid foam boards but that is because the spray foam creates a air tight seal to the wall studs.

But once again, you cannot just drill a hole and add spray foam into wall or ceilings if there is already existing fiberglass insulation.

I would recommend leaving well alone and live with the fact that you have a RV, they are not generally intended for extreme weather conditions. They will not be as comfortable as a sticks and bricks unless you plan to rip out (gut) the interior, then stud in 2" or 4" and fill the walls with spray foam.. A very big and costly job and you lose a lot of interior space.

[wopachop]

Oh darn. Will go take a looksie.

[gbopp]

I may be wrong, again, but I don't think the insulation blowers from HD and Lowes are capable of blowing insulation into walls.
They're just for spraying in open attics.