insulation, Floor

[JohnEd]

  :)I recently read a post that mentioned that he had the first 1/2 ply layer of his floor installed.  He went on to say that he would be installing a layer of "sound insulation" next and finally put in the second 1/2 inch ply layer.  What material could be used for this?  Sound is important to me but heat and cold loss is even more so.  I had not heard of this laminating scheme before and I admit to leading a sheltered life, but I did envision this using 1 inch of polyiso alu baked foam sheets.  I thought it would support the weight of whatever was on top of it and one inch of the stuff is lots of R value.  I have read posts by guys that had their walls and ceil sprayed and they said they couldn't hear their engine run afterwards, it was that quiet.  Is sound insulation even warranted in the floor.  If I need to use somthing besides foam between the plywood sheets I am all ears.  Actually, I have a ton of questions on the floor subject.

Thank You

JohnEd

[Dallas]

Damn, I lost my connection so I have to do all this again I think
If I were doing it, instead of using polyisocyanurate, which becomes brittle and breaks down over time, I would use a system something like this:
3/8" Marine grade plywood or 3/8" pressure treated plywood for the ability to repel moisture from underneath.
Next:
3/8" SSP-FL or SSP-FL Plus Sub floor sound and insulating membrane system
  From the soundproofing.org website:
    "Super Soundproofing-FL is a peel-and-stick non-permeable sheet membrane, which reduces impact and airborne sound transmissions and is a moisture/vapor barrier. Designed for use with engineered wood plank, wood parquet and laminate floors, it should be used where sound-control is required, specified, or desired.  Super Soundproofing-FL may be applied to structurally sound and clean surfaces, including: concrete; plywood; precast floor panels; OSB; ceramic tile; terrazzo; natural stone; Portland based leveling and patching compounds; cement backer board; existing VAT; VCT; and fully adhered vinyl floors.  Super Soundproofing is also approved for installation over radiant heated floors.

Super Soundproofing-FL's membrane is tacky on the bottom providing superior adhesion to concrete, steel, and wood substrates. The cross-linked poly-olefin foam top sheet makes an excellent bonding surface for approved wood flooring adhesives and will not dry out or decay with time. It also contains no V.O.C's and is environmentally safe".

The website address is:
http://soundproofing.org/sales/reduce_floor_noise_with_our_underlayments.htm

Next, I would put in 3/8" CDX underlayment or two layers of 3/16" Luan, giving me a great surface to apply a final floor surface to.
My choice, when I get the time, money and my wife out of the bus for two weeks, is to obtain either standard white oak flooring or a quantity of hickory from a friend of minme with a saw mill. With the hickory I will surface plane it and the put it through the jointer to make random width planks for flooring from 3" wide to 12" wide.
It should add character and a feeling of openess with the random widths.
But, then do it your way.
IHTH
Dallas

[NJT5047]

Just how quiet do you want?  If my old MC9 is an example, it is quiet.   Correct me, but it seems that sealing up areas of the floor may become counterproductive.  Water incursion is going to happen.  Seems a better approach may be to let the floor breath and dry out if it becomes damp or wet.   
The only "noise" in my coach comes from the mirrors and wind against the front of the bus.  Even my EXTREMELY noisy genset isn't a problem inside the coach.   Wish I could hear more of the engine...only a little turbo/blower sound up front.   Minimal engine sound.  Easily talk to Terri who's sitting way over on the other side and doing the driving...I just hold the wheel.
Dallas, have you put your floor soundproofing into "$" yet?  Sounds expensive.  Some insulation is probably a good idea, but all that soundproofing sounds like overkill.  Is a GM bus noiser than an MC9?  If using a coach is really cold weather, the utility compartment must be heated to some degree, so floor insulation becomes questionable in that area.   
Thinking about it, my water pump makes the most noise inside the coach.  That thing will get isolated...someday. 
Or changed out for one of the constant pressure pumps.   Not on my priority list. 

[NJT5047]

Dallas,  where you going to place the freshwater storage?   
The "wiggly" bus with the floor removed is interesting.  Wouldn't have thunk it would have any structural effect on the coach.   I'm sure that you're aware that custom plywood can be purchased in about any size you can handle.  Costs, but it may solve some problems.   
You can show me in May...Now you gotta do a demo!   You got that pig yet?  I'm already getting hungry thinking about that thing!  You got any local band members that need a bass player?    Didn't realize it but two weeks before your get-together, we are opening for the old band Pure Prairie League.  I think that they did Aimee or somthing similar.  I'll bet they aren't as old as I am.     Or maybe they'er closing for us?  Ya that sounds better.   I'm trying to get you some entertainment.  Only problem is that our travelling music  buddies are just returning home from the Denton, NC affair.  We'll  be there too.   Then we catch you for the long weekend, back two weeks and gone again for two more weekends.   They'll show...likely.  Haven't driven 400 miles total yet this year.  And that's how this year's going to be.   
I'll need a tour of your coach too.  Don't remember ever being inside a GM bus. 
Best, JR    White Knuckle Express !       

[NJT5047]

Uummmmmmmmmmm Dallas,  What's the little troglodite standing by someones' foot? 
Never seen one of those that I can recall.   It appears to have a tooth...could be dangerous. 
I suggest you run away from that thing.   Be very careful! JR

[JackConrad]

I just finished the floor in a 102A3 for a friend that wanted a layer of 3/4" R-Max (R value 5) placed on his floor, then a layer of 1/2" BC plywood. A grid work of 1/2 was instsalled first so that all edges of the plywood were on the 1/2s. 1/2 and plywood was screwed and glued using polyurethasne constuction adhesive. I also installed 2 layers of 3/4" R-Max with a layer of lead between them on the engine bulkhead in the rear of the bus.  This was also covered with 1/2 BC plywood. Although still an empty shell, the noise level from the engine was greatly reduced.  Hope this helps, Jack

[JohnEd]

Jack,

Thank you for your post.  "Sounds" like the way to go.

What is R-MAX and what is the source?  How thick was the lead sheeting?

Thank You

John

[onemule]

Gentleman, this quesstion/statement comes from one who would be considered  Pre-newbie, While in high school i worked for a motorhome company that solely worked on Cortez motorhomes, and at the time they were the elite , being all metal construction, My question is why arent you guys insulating the engine compartment? one it reduces HEAT and engine NOISE at the same time with less expence , and it does a wonderful job aat that. I say this because i haven't the money to raise my roof ,and i stand 6'2" all the overhead space to me is very valuable, and it seems like its alot more expensive to raise the floor  3 times 2 with plywood and the other with insulating foam or what ever. scold me if you must but ? is there not another way. Randall > onemule

[JackConrad]

Jack,

Thank you for your post. "Sounds" like the way to go.

What is R-MAX and what is the source? How thick was the lead sheeting?

R-Max is 3/4" thick tan foam (polyisocyanate) with aluminum foil on one side and a layer of thin white plastic on the other side. It is available at Home Depot, Lowes, etc. About $10-12 per 4x8 sheet. The lead I used was thicker than what I planned because they cut me a piece of the thicker lead. I paid for 1 pound per square foot (1/64"), but received 2#/square foot.   Jack

[Merlin]

... My question is why arent you guys insulating the engine compartment? one it reduces HEAT and engine NOISE at the same time with less expence , and it does a wonderful job aat that. ..  Randall > onemule

I assume you wish to keep HEAT from radiating into the living area.  From looking at the above posts, it seems the fellows are doing a heat+cold+sound insulating thing.  Sort of at least.  Nothing is perfect.  However to keep your engine from sending heat into the living area, there are a few good ways to help the situation.  I used what is called EHP (engine heat protection) on the underside of the bedroom flooring to stop much of the heat.  First thing the heat sees is the EHP which is a blanket of ceramic.   Then to keep huge amounts of heat IN the exhaust system, I purchased the wet blanket stuff from the same people who sell EHP.  When I get to it, the wet blanket will get wrapped around the in and out pipes of the turbo unit.  Some experts tell me this will improve boost and mileage.  Yet to be determined, however.

[Dallas]

Gentleman, this quesstion/statement comes from one who would be considered  Pre-newbie, While in high school i worked for a motorhome company that solely worked on Cortez motorhomes, and at the time they were the elite , being all metal construction, My question is why arent you guys insulating the engine compartment? one it reduces HEAT and engine NOISE at the same time with less expence , and it does a wonderful job aat that. I say this because i haven't the money to raise my roof ,and i stand 6'2" all the overhead space to me is very valuable, and it seems like its alot more expensive to raise the floor  3 times 2 with plywood and the other with insulating foam or what ever. scold me if you must but ? is there not another way. Randall > onemule

One Mule,
One of the reasons I don't insulate the engine room is that it's awefully tight in there, even with my 671, clearance on the back side between the water manifold and access door is only about 1½". That's not a real joy to stick your hand behind at the best of times!
I also have a Flx Metro here that has even less room.
Dallas

[Busted Knuckle]

Gentleman, this quesstion/statement comes from one who would be considered  Pre-newbie, While in high school i worked for a motorhome company that solely worked on Cortez motorhomes, and at the time they were the elite , being all metal construction, My question is why arent you guys insulating the engine compartment? one it reduces HEAT and engine NOISE at the same time with less expence , and it does a wonderful job aat that. I say this because i haven't the money to raise my roof ,and i stand 6'2" all the overhead space to me is very valuable, and it seems like its alot more expensive to raise the floor  3 times 2 with plywood and the other with insulating foam or what ever. scold me if you must but ? is there not another way. Randall > onemule

One Mule,
One of the reasons I don't insulate the engine room is that it's awefully tight in there, even with my 671, clearance on the back side between the water manifold and access door is only about 1½". That's not a real joy to stick your hand behind at the best of times!
I also have a Flx Metro here that has even less room.
Dallas

Dallas keep hammering you'll make it to 100 post before the end of the hour! Knuckle

[DavidInWilmNC]

What I've thought to do for floor insulation in my MC-8 should be fairly easy.  While I'm replacing the plywood floor, I'm going to cut 1.5" Styrofoam sheets to fit up against the floor (or ceiling of the bay, however you want to look at it).  Of course, I'll lose some insulating areas due to the frame spanning side-to-side, but about 95%+ will be covered.  I'll either glue this to the bottom of the floor and screw it up with 2" deck screws through large fender washers or cover it with luaun from below for a nice, durable ceiling in the main storage bay.  I'll insulate the engine area using the same material. 

Now, for a couple questions.  Do you guys isolate the floor from the frame with anything or use an adhesive to keep it tight and squeek-free (with minimal isolation)?  In the inside rear over the engine, have you removed the panels over the engine to isulate or just insulated over it then covered this with plywood?  I'm at the point where I'm about ready to replace the floor, insulate, and check the air beams.  Insulating the engine areas will be mixed in with this.

Thanks
David

[Dallas]

Gentleman, this quesstion/statement comes from one who would be considered  Pre-newbie, While in high school i worked for a motorhome company that solely worked on Cortez motorhomes, and at the time they were the elite , being all metal construction, My question is why arent you guys insulating the engine compartment? one it reduces HEAT and engine NOISE at the same time with less expence , and it does a wonderful job aat that. I say this because i haven't the money to raise my roof ,and i stand 6'2" all the overhead space to me is very valuable, and it seems like its alot more expensive to raise the floor  3 times 2 with plywood and the other with insulating foam or what ever. scold me if you must but ? is there not another way. Randall > onemule

One Mule,
One of the reasons I don't insulate the engine room is that it's awefully tight in there, even with my 671, clearance on the back side between the water manifold and access door is only about 1½". That's not a real joy to stick your hand behind at the best of times!
I also have a Flx Metro here that has even less room.
Dallas

Dallas keep hammering you'll make it to 100 post before the end of the hour! Knuckle

BK,
Nope, It's nap time for us old guys.
Maybe after lunch and nap.
Dallas

[FloridaCliff]

JohnEd,

I did similar to Jack. 

Made a huge difference on noise and just walking across the plywood overlay it feels solid and quieter.