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Underlayment [message #67301] Sat, 12 December 2009 22:24 Go to next message
Chr$ is currently offline  Chr$   United States
Messages: 2690
Registered: January 2004
Location: Scottsdale, AZ
Karma: 1
Senior Member
Folks,

I'm getting close to putting in my hardwood laminate flooring. I plan to use the "Quiet walk" fiber pad under it. I will be cutting it around my swivel seat bases for the Honda seats and trim with bezel that came with them. My couch, on the other hand, I was planning to bolt through it since it needs to be a bit higher. To those of you who used the snap together floating floor a few questions:

1. Did you use an underlayment such as 1/4 inch plywood or OSB or just cover the stock floor.

2. Have you had any issues with bolting things through it to the frame?

3. Do you have any issues with the joints due to the coach floor flexing? (Seems to flex a bit).

4. Any other tricks you guys learned the hard way so I don't have to? Very Happy

I do plan to fill all the little holes and such with silicone. That floor is like a piece of swiss cheese. Some of the countersunk bolts don't even go into the frame...

Thanks in advance!


-Chr$: Perpetual SmartAss
Scottsdale, AZ

77 Ex-Kingsley 455 SOLD!
2010 Nomad 24 Ft TT 390W PV W/MPPT, EV4010 and custom cargo door.
Photosite: Chrisc GMC:"It has Begun" TT: "The Other Woman"
Re: Underlayment [message #67304 is a reply to message #67301] Sun, 13 December 2009 00:32 Go to previous messageGo to next message
Dan Borlase is currently offline  Dan Borlase   Canada
Messages: 743
Registered: May 2008
Location: Kelowna B.C. Canada
Karma: 0
Senior Member
Chris...
I put in a cork laminate floor two years ago with an insulating
foam underlay. No indication of a problem of any kind.
I sealed the original plywood with an anti mold/fungus paint
toseal the wood. As you planed to do, I filled all holes with
silicone. Very warm, very quiet, and easy to keep cleen.

Dan "Looking forward to the Barrett-Jackson in January" Borlase
Re: Underlayment [message #67313 is a reply to message #67301] Sun, 13 December 2009 06:54 Go to previous messageGo to next message
rgleas is currently offline  rgleas   United States
Messages: 48
Registered: May 2009
Location: Tulsa, Ok.
Karma: 0
Member
I have a 76 Glenbrook the PO installed a laminate floor just before I purchased the vehicle. I have installed several laminate floors myself so I am familar with the process.


1. Did you use an underlayment such as 1/4 inch plywood or OSB or just cover the stock floor.

I do not believe the PO used any underlayment.

2. Have you had any issues with bolting things through it to the frame?

Everything is bolted through the floor.

3. Do you have any issues with the joints due to the coach floor flexing? (Seems to flex a bit).

I have one joint in the halway that is apart. I believe this was do to the installation as it would have been the last piece installed. Otherwise no problems.


4. Any other tricks you guys learned the hard way so I don't have to?

No trick to it.
Re: [GMCnet] Underlayment [message #67322 is a reply to message #67313] Sun, 13 December 2009 09:14 Go to previous messageGo to next message
powerjon is currently offline  powerjon   United States
Messages: 2446
Registered: January 2004
Karma: 5
Senior Member
Roger,
I just installed a Pergo floor in our coach last week. I used the
American cottage series number 80140 Summer Hickory. It is the high
end of laminate flooring and comes with a foam underlayment adhered to
each piece. The lower cost laminate floors without the foam backer
require that you use the foam underlayment that come on a roll. No
additional underlayment is required if the substrate is in good
condition. Our floor in the 77 coach was without any issues and none
of the bolt heads extended more than 1/8". Laminate floors float and
flex naturally and should not cause any problems. Floors that have
problems most of the time did not have enough expansion space
typically 1/4" on all outside edges. I have friends that have
laminate floors in there GMC's and they seem to be very durable and
without any problems.

Here are the pictures of the before, during and finished flooring.

<http://www.gmcmhphotos.com/photos/showgallery.php?cat=5344>

J.R. Wright


>
>
> I have a 76 Glenbrook the PO installed a laminate floor just before
> I purchased the vehicle. I have installed several laminate floors
> myself so I am familar with the process.
>
>
> 1. Did you use an underlayment such as 1/4 inch plywood or OSB or
> just cover the stock floor.
>
> I do not believe the PO used any underlayment.
>
> 2. Have you had any issues with bolting things through it to the
> frame?
>
> Everything is bolted through the floor.
>
> 3. Do you have any issues with the joints due to the coach floor
> flexing? (Seems to flex a bit).
>
> I have one joint in the halway that is apart. I believe this was do
> to the installation as it would have been the last piece installed.
> Otherwise no problems.
>
>
> 4. Any other tricks you guys learned the hard way so I don't have to?
>
> No trick to it.

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J.R. Wright
GMC GreatLaker
GMC Eastern States
GMCMI
78 30' Buskirk Stretch
75 Avion Under Reconstruction
Michigan
Re: [GMCnet] Underlayment [message #67341 is a reply to message #67322] Sun, 13 December 2009 12:13 Go to previous messageGo to next message
Harry is currently offline  Harry   Canada
Messages: 1888
Registered: October 2007
Location: Victoria, BC CANADA
Karma: 3
Senior Member

There is no such thing as "hardwood laminate".
I hate laminate. It's made of sawdust. But....I have it in my house. If I were to do it again, I would buy the very best, individual plank type. I would seal all the edges before putting it in a motorhome, so no moisture gets in to it. I might even glue the edges as it goes down. When and if I do my GMC, I will use real hardwood. I'll plane it down to a thickness that works best.
Re: [GMCnet] Underlayment [message #67360 is a reply to message #67322] Sun, 13 December 2009 15:40 Go to previous messageGo to next message
Gary Casey is currently offline  Gary Casey   United States
Messages: 448
Registered: September 2009
Karma: 0
Senior Member
Claude,
By the way, are you located in Montreal? Just curious.
Gary



________________________________
From: John Wright <powerjon@chartermi.net>
To: gmclist@temp.gmcnet.org
Sent: Sun, December 13, 2009 8:14:29 AM
Subject: Re: [GMCnet] Underlayment

Roger,
I just installed a Pergo floor in our coach last week. I used the
American cottage series number 80140 Summer Hickory. It is the high
end of laminate flooring and comes with a foam underlayment adhered to
each piece. The lower cost laminate floors without the foam backer
require that you use the foam underlayment that come on a roll. No
additional underlayment is required if the substrate is in good
condition. Our floor in the 77 coach was without any issues and none
of the bolt heads extended more than 1/8". Laminate floors float and
flex naturally and should not cause any problems. Floors that have
problems most of the time did not have enough expansion space
typically 1/4" on all outside edges. I have friends that have
laminate floors in there GMC's and they seem to be very durable and
without any problems.

Here are the pictures of the before, during and finished flooring.

<http://www.gmcmhphotos.com/photos/showgallery.php?cat=5344>

J.R. Wright


>
>
> I have a 76 Glenbrook the PO installed a laminate floor just before
> I purchased the vehicle. I have installed several laminate floors
> myself so I am familar with the process.
>
>
> 1. Did you use an underlayment such as 1/4 inch plywood or OSB or
> just cover the stock floor.
>
> I do not believe the PO used any underlayment.
>
> 2. Have you had any issues with bolting things through it to the
> frame?
>
> Everything is bolted through the floor.
>
> 3. Do you have any issues with the joints due to the coach floor
> flexing? (Seems to flex a bit).
>
> I have one joint in the halway that is apart. I believe this was do
> to the installation as it would have been the last piece installed.
> Otherwise no problems.
>
>
> 4. Any other tricks you guys learned the hard way so I don't have to?
>
> No trick to it.

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Re: [GMCnet] Underlayment [message #67362 is a reply to message #67301] Sun, 13 December 2009 20:30 Go to previous messageGo to next message
Rick Denney is currently offline  Rick Denney   United States
Messages: 430
Registered: January 2004
Karma: 0
Senior Member
Chris Choffat writes...

> 1. Did you use an underlayment such as 1/4 inch plywood or OSB or
> just cover the stock floor.

I used the cheap stuff everyone else says is no good. I did not put
anything on the original floor except the rolled 1/8" foam pad. My
original floor sags at the edges by a significant amount--as much as
3/8". I put some shims under the edge of the floor adjacent to the
door, and spaced them so that the laminate panels didn't span more
than about 6 or 8 inches. I patched my rotted floor section next to
the door by first grinding out all the rotted stuff, then soaking it
in penetrating epoxy wood restorer, and then filling it with Bondo
construction filler (not body filler!). The area was small enough to
make this seem an appropriate way to go. The laminate is hanging in
mid-air, probably, on the other end where it is under the dinette
table. Given that nobody will ever stand there, I didn't worry about
it. I did not attach the flooring at all, and put trim around the
edges to hold it down. I left the laminate short so that the trim is
attached to the original floor without going through the laminate,
allowing the laminate to fully float.

> 2. Have you had any issues with bolting things through it to the frame?

I haven't had a reason to bolt through it to the frame, except right
at the door threshold. No issues so far, and the coach is subject to
extreme temperature and humidity changes.

> 3. Do you have any issues with the joints due to the coach floor flexing? (Seems to flex a bit).

I did not glue the laminate sections and have had no problems so far.

> 4. Any other tricks you guys learned the hard way so I don't have to? :d

One reason I didn't attach it to the floor firmly is that I want to be
able to remove it and replace it in the future without having to
destroy stuff. Too much on this coach was done with the idea that it
would never have to be done again.

> I do plan to fill all the little holes and such with silicone.
> That floor is like a piece of swiss cheese. Some of the countersunk
> bolts don't even go into the frame...

I figured the foam pad would seal up anything that wasn't sealed that
well, but in fact most of the holes in mine were in other parts of the
coach. I have patched those, but not with silicone. In some cases, I
screwed down aluminum plates to seal holes.

On the subject of durability, I suppose I trust the dimensional
stability of that sawdust stuff more than real boards. Real hardwood
boards swell and shrink across the grain with changes in humidity by a
substantial amount. The laminate is waterproof so it swells and
shrinks only in relation to temperature changes.

And after I installed mine, I left a piece sitting out on the ground.
After a year of being rained on, blasted with much sun, snowed on,
covered in ice, and driven over with my 1200-pound Kubota tractor, it
has only showed very slight moisture encroachment at the edges. In the
relatively dry coach, I don't expect it to degrade in my lifetime. But
I didn't fasten it down, and if it does, I can throw new stuff in
there in an afternoon.

Rick "who put the floor in around the fixtures, not under them" Denney

'73 230 Ex-Glacier "Jaws"
Northern Virginia

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'73 Glacier 230 "Jaws"
Re: [GMCnet] Underlayment [message #67363 is a reply to message #67341] Sun, 13 December 2009 20:37 Go to previous messageGo to next message
Chr$ is currently offline  Chr$   United States
Messages: 2690
Registered: January 2004
Location: Scottsdale, AZ
Karma: 1
Senior Member
Harry, thank you for your opinion. Of course, there is no such thing as hardwood laminate. It's just what it people call it. Yes, it is composed of sawdust, glue, and has a picture of hardwood printed on it covered with plastic, but seems to also be the best solution to an environment that will flex, twist, bend, be subject to 0-100% humidity and freezing to 140 degree temp swings, and be walked on by my retriever. Since "real" hardwood needs to acclimate to the relatively benign environment of a home before being laid, I think the worst place to use it is my coach.

It is also cheap, easy to install, and easy to replace.

By the way, how do you know that the sawdust didn't come from hardwood? Laughing


-Chr$: Perpetual SmartAss
Scottsdale, AZ

77 Ex-Kingsley 455 SOLD!
2010 Nomad 24 Ft TT 390W PV W/MPPT, EV4010 and custom cargo door.
Photosite: Chrisc GMC:"It has Begun" TT: "The Other Woman"
Re: Underlayment [message #67386 is a reply to message #67301] Mon, 14 December 2009 07:59 Go to previous messageGo to next message
petemosss is currently offline  petemosss   United States
Messages: 221
Registered: August 2008
Location: Jacksonville, Florida
Karma: 0
Senior Member
Chri$, Harry,

My rotted spots in flooring has been cut out and replaced with exact dimensional equivalents of the Komerflex expanded pvc and will be epoxy fiber glassed in. 2 different mm thicknesses are required to make up the 1" plywood in earlier coaches. This is where I'm at.

My floor still has some give to it in spots and will be skinned with a 2mm Exterior Grade Luan sheets used for skinning exterior doors. Moisture cure urethane floor glue for wood floors will be used for attaching the sheets. (@ $11.00 4x8 sheet at a serious plywood dist. not home box store.) Creates thermal and vapor barrier and tightens up floor. (Thanks Jim B!)

The thought of that mm thin Chinese made foam under flooring makes me cringe. I see how well the rest of that has held up in the coach. It's all crumbled into black dust.

I have not had the best luck with the pergo type click floating systems in residential applications and will stick with what has worked for me in the past. Real wood flooring.

Harry, you don't have to go to all the trouble. Somebody has already done it for you and applied a 50 yr warranty. http://www.lumberliquidators.com have stores most of the USA and feature their Bellwood Brand. It is finished on all edges but the back and is indestructible. I dropped a 25 lb cast iron griddle from a ceiling mounted pot rack striking with a corner of it and it didn't even scratch the Black Walnut floor at all. I have nailed the first 2 projects I did and recently glued a floor for moms kitchen for practice and it worked great except having to stop constantly to clean your hands of that drop of glue that will reappear all over the finished surface. We both have wood frame houses built off grade so we'll frequently have 100 deg with 100% humidity under the house and 70 deg. 50% humidity inside and I haven't noticed any expansion or contraction issues in the last 5+ years.

Last weeks purchase- 2 boxes (@50sq. ft. ea.) 5/16" x 2 1/4 select Cherry on close out for $.99 sq. ft. Less than $100. to do under everywhere but my modules.

just what I'm doing.


Pete 74 Canyon Lands 26' "Emery"
Re: [GMCnet] Underlayment [message #67394 is a reply to message #67301] Mon, 14 December 2009 09:22 Go to previous message
Steven Ferguson is currently offline  Steven Ferguson   United States
Messages: 3447
Registered: May 2006
Karma: 0
Senior Member
Chris,
We put a Pergo snap together floor in our GMC about 8 years ago. I
used the 1/4" foam pad that the instructions recommended. I
removed all of the furniture, installed the floor, reinstalled the
furniture. Heat and cold still seem to allow the floor to "float".
We recently did the same to our SOB. I made the mistake of glueing
the trim to the edges of the flooring and also to the walls. When the
humidity gets down to 5% small gaps appear between a few of the boards
because the glue keeps to floor from floating.
The recommended foam underlayment will hide most subfloor
irregularities so a new subfloor is not necessary.
On Sat, Dec 12, 2009 at 8:24 PM, Chris Choffat <cchoffataz@yahoo.com> wrote:

> I'm getting close to putting in my hardwood laminate flooring. I plan to use the "Quiet walk" fiber pad under it. I will be cutting it around my swivel seat bases for the Honda seats and trim with bezel that came with them. My couch, on the other hand, I was pla removnning to bolt through it since it needs to be a bit higher.  To those of you who used the snap together floating floor a few questions:
>
> 1. Did you use an underlayment such as 1/4 inch plywood or OSB or just cover the stock floor.
>
> 2. Have you had any issues with bolting things through it to the frame?
>
> 3. Do you have any issues with the joints due to the coach floor flexing? (Seems to flex a bit).
>
> 4. Any other tricks you guys learned the hard way so I don't have to? :d
>
> I do plan to fill all the little holes and such with silicone. That floor is like a piece of swiss cheese. Some of the countersunk bolts don't even go into the frame...
>
> Thanks in advance!
> --
> -Chr$: Perpetual SmartAss
> 77 Ex-Kingsley 455: The Engineer's Motorhome
> Scottsdale, AZ
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Steve Ferguson
'76 EII
Sierra Vista, AZ
Urethane bushing source
www.bdub.net/ferguson/
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