wmcgarva,
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 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.
Have fun!
Jim