Underlayment for a hardwood floor....

[Ncbob]

I did a search of the archives and could only come up with one thread on the subject....all that being said...I found it a bit confusing.

Jack recommended a product which he said he used with lead shielding but no source for the lead.  Dallas made a recommendation in words too big for this country boy to comprehend.

Here's my situation... I would like to put a 3/8' - 1/2" plywood floor over the existing bus floor in my MC5A and kill not only the hollow chamber effect of the storage bays and also end up with a reasonable amount of insulation and vapor barrier because we plan on installing a glue down hardwood floor throughout the bus.

We live in Podunk, USA and have only a Lowes where the former hamburger flippers from Mac Donald's go to round out their retirement...not a lot of viable information there.

So, if you've been where I am and can offer any advice of a NAMED product, and perhaps a source, I'd be most appreciative.  I only want to do this job once...I don't have another bus in me...so me and m'darlin' would be most appreciative.

Jump in here...let's kick this thing around and put something worthwhile in the archives........

Thanks,

NCbob

[FloridaCliff]

Bob,

Depends on how much insulation you want to put in and how much headroom you are willing to give up.

If not much I would put the underlayment for Laminate floors.  About and 1/8 thick and has a vapor barrier.

They sell it at all Lowes....Even in Podunk...

Cliff

[gears80]

I am in the process of putting down a floor in my mc5 also. I was thinking of 1" of foam with 1/2" of plywood. At my hight I would still have head room.

[FloridaCliff]

Gears,

If you do the 1" foam, make sure amd put some wood strips of the same thickness at at least 2'  on center below your plywood.

Even though the foam is dense it can compact over time, the strips will prevent this. (credit to Jack Conrad)

I did it on mine and am very happy with the results and "feel" of the floor.

Cliff

[Ncbob]

One of my first concerns is the toxicity of and of the closed cell foams...and consequently I'm staying away from them.

My wife is handicapped and I'm not a youngster and while we don't anticipate a fire of any sort...I don't want to have to bail out of a window and have her fall on me in order to save our lives from suffocating.

FWIW

NCbob

[Melbo]

NC

There are a lot of "foams" that will not burn with the toxic fumes and they are available most everywhere.

I am thinking mostly of glass fiber insulation that is used under concrete slabs.

Insulate and you will be much happier

Melbo

[gears80]

I was planing on using strips. When you put a floor down should I keep the center accessible?

[FloridaCliff]

Gears,

Can't speak for you MCI-5, but I made several access panels to under floor areas.

On mine there is muffler bolt, fuel tank (top), clutch linkage, wiring pull point.

You know the rule "If you make access, you will never need it.  If you dont!...." 

Cliff

[prevost82]

When I put down my laminate floors I used 1/4" cork underlay that was 2ft x 4 ft. Cork has good sound transmission seperation and insulating quailities. The floor are warm and we can't hear anything from the bays or tires.
Ron

[Oregonconversion]

Is there a big difference when you insulate the floor?

I was thinking about just plywood over the original.

[Ednj]

Here you go Bob,

http://www.thermotec.com/products/full/14100/14100.html

http://www.b-quiet.com/index.html

http://www.b-quiet.com/brownbread.html


http://www.westmarine.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10001&langId=-1&catalogId=10001&productId=17973

I used the bruce hardwood 3/8"x3" and nailed it down to 1/2" ply over the oringinal 3/4" floor.
Insulate the ceilings in the bays.
I tried the pergo real wood 3/8x3" but I didnt like it.
I know=

[cody]

Bob, there are many ways to approach the subject, the most effective sound barrier is a lead based product, it's available as a 1/8 to 1/4 inch sheet 4 ft wide     http://www.soundproofing.org/infopages/flooring.htm    The most cost effective way to go is a cork based sheeting tho, it's reasonably quiet and will insulate to a degree, kinda hits both side of the coin without dipping deeply into headroom options, (that uses up all my big words tho lol) Now what I did was to sandwich a layer of 3/4 inch foil faced foam board between my subfloor and finished floor, I used 3/4 in furing strips set on 2ft centers to maintain the integrity of the foam. 

[JohnEd]

NCBob,

A number of points you made are out of the "mainstream" as I know it.

1.  Lead sheeting is a superb noise barrier.  I have only seen/heard of it being applied over the engine bay/compartment where it has performed amazingly well.  1/16 - 1/8 and glue it6 down securely with contact cement that needs lacquer thinner for cleanup.  Rubber mallet it in around rivets and seams and over corners.  With the mallet it stretches/compresses and forms a perfect bond/contour.

2.  I have never heard any mention of "booming" of the bay chambers.  I think I understand full well what you are talking about, however.  Today your bays are empty and make superb echo chambers.  When your bus is completed those bays will be full of "stuff" like tanks and generators and pers. items, etc.  I think the BOOMING will go away or we would have heard a lot more about it around here.  The booming "must" be coming up through the bottom of the bay and that being unloaded it will act more like a drum head than after "stuff" is on it.

3.  Put foam sheeting on the floor of the bays and plywood over that.  Insulates the bay and indirectly the floor a little.  Your wet bay should be insulated on the floor, overhead, sides and doors.  And it needs to be heated somehow.  Planning!

4.  I think you need to get over your missgivings about foam sheeting as an insulator for the floor.  I don't know of anybody that has insulated their floor that has done it another way.  Remember CLOSED CELL only and that Isocynurate stuff with foil is the best.  None of the foam approved for homes will "sustain fire" but it all can be burned.  Some of it outgasses a particularly lethal substance but they will all kill you.  They have to be burning pretty hot before that happens and if you are still in there you are long dead by that time.  Carper and pad will both add to the insulation but both produce lethal gases when burnt.  Aircraft us the most "non burning" stuff in the world and it will still kill you when it gets hot enuf.  Your concern for your wife's safety and well being is thoroughly admirable.

5.  Concerned with sound/quiet?  Then you must be going to "spray foam" the walls and ceiling...right?  The absolute best move for insulation and quieting.  Find a co that does it someplace you can drive to and get bids.  You need closed cell and I don't know which version of that is best.  Beware....there is a new water based stuff out there that absorbs water and is open cell.  DO NOT USE THAT STUFF.

6.  You NEED smoke detectors at both ends of the bus, propand detectors near the furnace outlet and CO someplace.  Read the mfr's suggestions for location.  Put over temp sensory in the engine bay and baggage compartments especially the generator compartment. Fire extinguishers are a must have item and more than one is needed at at least both ends of the bus for obvious reasons.   RVSAFTYMAN is on this board and he sells nontoxic extinguishers, engine and generator and bay overtemp alarms.  Recently a Knut had a overtemp situation in his gen compartment and the system RVSAFTYMAN sold him saved his generator and probably his bus.

7.  Buses, like all RVs, get extremely hot in sheer seconds with a fire breaking out.  The imperative is to GET OUT IMMEDIATELY....no matter the drop out the window.  You can't even run 10 feet towards the fire to use the door.  Move away and get out the emergency exit.  With your wife's condition I would be paying a lot of attention to how that emergency exit worked.  Remember, the temp at the ceiling gets incredibly hot in seconds so staying low is an imperative.  I sound like a Fireman and I'm not.  Get cozy with RVSAFTYMAN and no he and I are not related.

8.  Read GUMPY's site extensively.  HUGE store of info there.

Keep posting and more will come up on each post from many Knuts.

Good luck and we all look forward to following your adventure closely.

John

[NewbeeMC9]

Is there a big difference when you insulate the floor?

I was thinking about just plywood over the original.

Do it your way.  My bus was done like that by PO and I have to recommend not doing that way if possible, if you are at the stage of pulling up plywood.

-taking up old plywood
-cleaning thoroughly( you'll see why if you look under there)
- seal all around top of wheel wells( driving in rain and trapped dirt makes a place for things to grow ) then spray foam all around them.
- figure out how you can use the extra space, extra freshwater tank etc.
      -maybe make below deck cabinet under center aisle
-run wire, extra conduit back to front for later  use if needed,

then go back with your choice of multilayer insulation and plywood.

your call, just hope this info of my regrets helps

[JohnEd]

KnuB,

I have heard your expression of regret many times on this matter.  MANY.  I didn't get that he was contemplating leaving the original floor down and not getting that nightmare of old corruption out from under the center isle.  I was told that in wet weather you cannot stop the foul odors from emanating from that XXXX...guess that was your experience as well.  Nice of you to warn him....I missed it,

Thanks,

John