View Full Version : How is my LM underbelly insulated? What precautions should I take?

10-26-2008, 06:17 AM
We have just taken delivery of a new Landmark Augusta. There are plans in the works for a Christmas trip to Massachusetts so this information would be very useful in our decision. I am a little hesitant as I do not want to damage any of the equipment. Any advice from the experienced members would be very helpful.

10-26-2008, 10:27 AM
I think we could use a few more details. For instance what are the circumstances that give rise to you taking precautions. It could be squirrels or a lot of other things. (I have lots of experience with squirrels and it is mostly bad - just my luck)

10-26-2008, 08:33 PM

Generally speaking, (and from memory so pretty accurate but maybe not exact) for the Landmark, and I will assume you have a model year 2009, the insulation and barriers would be as follows:

A continuous sheet of Coroplast (http://www.coroplast.com/product.htm) is fastened to the bottom of the frame using self-tapping screws and fender washers. This material spans the width of the outer edges of the I-beam frame members and runs from the rear cap to the front of the coach. When one refers to our underbelly material, it is this Coroplast. This is what keeps stuff out of the underbelly and is your first layer of protection.
Now inside the underbelly, on top of the Coroplast, is a sheet of Double-Layer Flex -Foil insulation.
Also inside, on top of the Flex-Foil insulation is a layer of Fiberglass insulation.
On top of and in between the Fiberglass insulation will be cross-framing members, plumbing lines, electrical lines and some dead air space.
You are now at the deck of the frame. On top of the deck, we set our laminated flooring system. This system is made up of aluminum framing with block foam insulation inside the cells that make up the frame. The floor is built up (laminated) by using a Darco underwrap moisture barrier material on the bottom, followed by a Luan sheet, then the floor (aluminum framing with block foam). On top of the floor is a single sheet of Wyerhauser Structure Wood which becomes the top deck of your interior floor. All of this is glued up between layers, then the entire piece goes into a Vacuumformer for about 22 minutes to suck all the air out and draw the glue into all void and super-bond the structure into one heck of a solid floor.
Once the laminated floor system is placed onto and bolted to the top deck of the frame, we apply the floor coverings (lino/carpet).

Point to all of the above is there are a lot of layers of protection between your feet on carpet and the ground below.

In terms of heat to the tanks and plumbing lines in the underbelly area, a duct from the LP furnace is placed into the underbelly to blow hot air into it.

Other precautions to consider:

If you ever plan to camp in below freezing weather for extended periods of time, I would consider having tank heating pads added to all of your holding tanks.
Others here if you are interested, can assist you with ideas on what other cold-weather precautions must be taken (insulated water/sewer lines etc.).

Please download the Landmark COnstruction Booklet from the factory site at this URL (http://heartlandrvs.com/downloads/LMConstruct.LO.pdf).

Have fun!


10-27-2008, 08:02 PM
Congratulations on your new coach and welcome to the Heartland family.

I have a precaution for you. Since you probably have an ice maker and maybe water in the door of you referigerator you should know that the water supply line for that is not routed through the trailer within heated areas. Because the refer is in a slideout the supply line is routed on the outside of the rig along the I-beam and is wrapped in black plastic wire loom. I have attached some pics for you to see. What I do not have a picture of is the shutoff valve behind the UDC and basement wall. Unfortunately if you are going to be in a cold climate you may want to blow out the lines for the icemaker and water in the door.

What I did to winterize the refer portion of my coach was to turn off the supply line behind the UDC, then I loosened the compression nut at the valve. I then made an attachment for my air compressor to connect the compressor to the compression nut. I set the regulator on the compressor to 20 lbs. per the suggestion in the Dometic instruction manual. I then turned on the refer, got a cup and tried to get water out of the door. When I pushed on the door switch to get the water I got some water and some air. I continued to do this until I felt all the water was out. I also activated the icemaker per the manual to get air through it also. This system that I decided to do is a bit different than that of the Dometic instructions but I like it a bit better. I wish I had pics to show you but I just have not had time to doucment what I did.

Hope this helps,

10-27-2008, 08:32 PM
Our north trail flooring and under belly, is this the same under belly set up for all makes ??

Good info by the wayNone

I love this forum for all the info