Living in the Southern USA, one undeniable fact is the intense summer heat. Before air conditioning, it’s hard to imagine how people managed. Personally, I can endure cold weather without a heater—just light a fire. However, when faced with 90-degree temperatures and humidity exceeding 60%, all you can do is sweat. There’s only so much clothing you can shed! LOL

Living in the South made it essential to install an air conditioning unit in Loki. Initially, we opted for a budget-friendly solution: a traditional home window unit in the van’s top back shelf space. We thought it would be cheaper and more inconspicuous outdoors (properly ducted, of course). However, that plan was short-lived. We bought one on Amazon for about $350, but it didn’t quite fit the space between the original metal roof and the current high-top roof. So, we returned that unit and eventually decided to invest in a Dometic FreshJet 3 traditional RV AC unit.

The unit itself proved excellent, albeit weighing over 65 pounds (which actually was a little less than the “low profile” Dometic Penguin models). Concerned about the fiberglass roof’s durability under that weight, we reinforced the roof and ceiling. According to the minimal instructions available, the ceiling needed to be between 1.5″ and 6″ thick and sustain a 250 pound load. Our fiberglass, even with reinforcement, was only about 1″ thick. We didn’t want to sacrifice too much headroom by creating a full ceiling throughout Loki, so we opted to reinforce only the area around the air conditioner. Here’s how we tackled it.

Wood for Framing

As always, when putting together a plan like this, a trip to Home Depot is essential. We purchased the wiring for the shore power and AC unit, along with the ¾” plywood needed for the “ceiling.”

Building the Frame

We cut two pieces of plywood, each with an appropriately sized hole for the AC unit. Precision was crucial, with the hole needing to fit within a ¼” tolerance range (instructions said plus or minus 2mm!) and be slightly off-center from front to back (though centered left to right). After cutting the first board, we used it as a template to mark and cut the second board. We then assembled them using Gorilla Glue wood glue and a staple gun to create a sturdy sandwich.

Next, to support the “ceiling,” we relied on the original metal roof/shelf inside the van. We constructed two leg frames (the I-Beam support) to ensure the weight rested on, or was transferred to, the metal frame rather than on the fiberglass. Working on a vehicle remodel presents challenges; unlike a house, nothing is perfectly square. Consequently, these supports had to be taller at the back than at the front.

Covering the Frame

Always up for a challenge, we then covered the portion of the “ceiling” that was going to be seen and the leg frame supports with a layer of cotton batting and denim.

The Finished Frame

The moment of truth came when we took it out to the van and it all fit in place quite nicely. Check out our next posts on running the wiring for the shore power and installing the AC unit in Loki.