Installing a Trailer Ceiling

Now that the major part of the heat and humidity is (I hope) nearly behind us, I was finally able to get out to the cargo trailer and get the main ceiling installed.

Due to the insulation being slightly thicker than its nominal value...by roughly an eighth inch...I was debating using the same kind of 3/8ths-inch plywood on the ceiling that was on the walls of the trailer, but the price was more than double the price of 1/4-inch luan, so the latter won out.

But the steel roof bows of the trailer were now shy an eighth of an inch of being flush, so I simply used some scrap paneling and cut strips, which I then secured temporarily with a couple of screws in each one. The ceiling would take care of the rest.

What made this trailer hard to work with is a compound bow of the front and top. For this part, we have to deal with both the bowed front as well as the bowed top, making the scribing of accurate lines a real trick.

What I came up with is a makeshift scribe cut out of the end of a scrap 2 x 2 and a short pencil...short only because it was what I could find that would work.

My makeshift scribe for marking the ceiling.

The idea is to set the pencil half-way into the piece of wood, so that the point is as close to being even with the edge of the wood as possible. To do this, I set the pencil on the table saw up against the blade, and then cranked the blade down to where the top of one of the teeth was at the center of the pencil. Since this pencil was hexagon shaped, that was easy.. When laying on one of it's flat sides, the center is a convenient "point" on one of the sides, so it was just a matter of setting the blade even with the point of the hexagon.

The pencil tip needs to be even with the edge of the board.

The notch was started using the rip fence, and then simply bumping the rip fence over a blade width for each cut. I wasn't worried about the length of the cut, as long as the screwdriver would lay into the notch. If I wanted to get fancy, I could have clamped a stop against the rip fence so that each cut was alike, but in this case, I guessed at it.

The next step was something to hold the pencil into the notch, and as you can see, a plain old rubber band, like the kind the postal carriers use to hold bundles of mail, worked just fine.

So the next thing was to hold the ceiling panel in the exact position (except for length) that it would be in. The sides were the most important, to line up with the pencil marks I had set. At the front, it was simply pushed against the fiberglass top nose of the trailer as far as possible. To hold it up, we (my wife helped lift it to the ceiling) used a couple of handy pieces.

The front ceiling panel held in position with temporary posts.

One was an old closet rod with some extra blocking for height under it and a flat piece on top so it wouldn't scratch the ceiling. The second was a jack bar that we bought at a truck stop to put under the extremely long front end of our truck camper when it was off the truck, just so in case someone climbed into the bunk, the whole thing wouldn't tip over.

We have found this trucker's bar to be extremely handy for many things, so it was a good investment for under $30. It already has heavy rubber pads on both ends. Normally the bar is used horizontally (and maybe vertically, too) to expand between the sides (or floor and top) of a trailer to keep cargo from shifting. It isn't very good for trying to "jack" anything up, as it has very limited travel and power, but for this purpose it was great. I also used it to hold the blocking pieces up when I was installing the ceiling blocking, and it worked like a charm.

When setting the ceiling panel in position it's important not to force it too tight to the ceiling, so you can bump it around and get it lined up properly. Then you can add some extra tension to keep it there.

The next thing is to use the scribe to mark the curvature. To do this, you hold the scribe flat against the front wall, so the pencil is even with the wall, and then gradually drag the scribe from one side to the other while holding it against the ceiling. The pencil should mark the exact curvature of the front wall onto the ceiling panel.

The scribe has to be moved sideways while keeping the pencil against the ceiling.

Once the mark was made, the ceiling panel was taken down, and moved outside the trailer, and then flipped over, so the pencil mark was facing up. I then used a saber saw to cut along the line and make the contour. Normally, you wouldn't want to use a saber saw that pulls up as it cuts on a finish side of a piece of paneling, as it causes it to splinter out. But in this case, there was blocking to be added to the first 1-1/2 inches, so any splinters would be covered.

Exact curvature of trailer front duplicated on ceiling panel.

Now that the curvature was cut, there was another thing to consider. All along the top of the trailer there are wires and many "fold-over" connectors for the inside as well as outside clearance lights. Those connectors have been known to fail. In case anything would ever have to be repaired, those must remain accessible (to a point).

In our trailer, I decided to add a filler piece to the front wall of the trailer. It will attach at the bottom to the front wall, but at the top, we needed some backing to secure it. To solve that problem I used some of the cut off scraps from the ceiling blocking, and cut them down to 8 pieces 6 inches in length. They were already 1-1/2 inches thick and about 1/1/4 inches the other way, plenty to serve as a backing for the future wall panel piece.

I laid them out, keeping the front edge flush with the edge of the paneling, balanced out the length side to side, and then glued each one in place. I used a couple pieces of scrap 2 x 4 on the underside, and then used individual clamps on each piece.

Blocking pieces being glued to the ceiling panel.

After a couple of hours of letting the glue set up during the hottest part of the day, I removed the clamps, flipped the panel over, and then used my Bostitch pneumatic staple gun to secure each piece with about 4 staples... just in case the glue ever dried out or let go.

At the top of the front wall of the trailer I had debated for a long time as to how to insulate around that curved wall and ceiling. Rigid insulation board would be a real pain to fit in that space. I had some leftover pieces of 10-inch encapsulated (wrapped in pastic) fiberglass insulation from when we did the house, so I decided to use that. It was thicker than I needed, but I didn't feel like taking it all apart to separate it into layers. I had one batt that was four feet long by 2 feet wide, so I did cut the width down so it would fit without bunching up too much, but I left the rest as is.

While the panel was down, I measured carefully from the front edge of the scribe (while holding it against the front wall), and got the measurements for the fan opening, as well as the last roof rib I needed to be centered on to secure the rear end of the panel. The fan, being centered, was easy enough to figure the other way. I made the fan opening cut with the saber saw, this time being careful to score just outside my pencil marks with a utility knife, so as not to splinter out the edges.

For the end cut, I transferred the mark to the back side, and then used my circular saw to make the cut, so that any splinters would be pulled toward the back side of the panel. I also used my 6-foot aluminum straight edge clamped to the panel to guide the saw in a perfectly straight line, making a finish cut as good as any factory cut.

The front panel was installed first, and screwed into the steel roof bows using the special screws that were so hard to get (see the previous post). Along the edge, I again used the Bostitch staple gun to secure the edges to the edge blocking as well as to go around the fan opening.

The second piece, to cover the rear half of the ceiling, was much easier, as the back of the trailer is straight across. To keep a tight seam where the two pieces meet, I measured the fan opening from that point, and then cut the opening and the rear cut the same way as was done on the front panel. This one also only needed one temporary post to hold up, as the back edge went over the rear door torsion spring. That part will all be hidden within the rear storage compartment as time goes on so it doesn't have to be real fancy. I did add one center piece of blocking between the last rib and the rear bulkhead, so that was used to staple the rear section of paneling above the torsion spring.

So now, the hard parts that consume a lot of time are all done, and the ceiling is finally in position and secured. 

The new luan ceiling finally done!

The curved ceiling edges on both sides will be fitted with sheet metal panning, and then cabinets will hide most of that, except for three places, (1) above the entry door, (2) inside the closet, and (3) above the head side of the rear bunk. The edge blocking at the sides of the main ceiling will be the anchor points for the fronts of the overhead cabinets, and any sheet metal will be behind and above, and won't be seen unless the cabinet's doors are open, Since everything else in the trailer will be eventually painted white, I plan to use pre-finished aluminum flashing material to form the curvatures and then it will be stapled in place along the edges. Where exposed, a piece of thin lattice will cover the joint.

Nothing more needs to be done with this part. I still have to obtain the correct adhesive caulk to seal the roof around the fans when I install them, but that can be done anytime now. We have to make a run to Batesville to get the commercial tile for the floor, so I will probably get the caulking at that time. The luan for the floor underlayment I can get locally, so that isn't a problem.

At this point we have "maybe" two days of 90+ degree weather yet (hopefully the last we will see this year), and then we have an abnormally cool front coming in, so now is the time to get busy on these outside projects.

Once the floor is down, I should be done with large sheets of plywood. Most of the rest will be much smaller pieces to cover the 1 x 2 cabinet framework, and I figure on doing most of that inside the trailer. Once the fans are in, I just need some temporary lighting and I can work out there all winter. A small electric space heater will be enough to take the chill off later on.

I probably won't even need to use the new air conditioner this year, but I needed it to be able to build the front couch around it, and create the necessary baffles under the couch. That will be the next thing after the tile floor is in. But it will be good to have it operational for next spring after it warms up again!

OK, now that you see how it's all coming together, what do you think? I know everyone has an opinion, so let's hear it. If not an opinion, how about questions? I'll be glad to answer anything on your mind.

Thanks for reading!

  

Blocking and Insulation

Since I only have a part of the blocking done right now, this post will be updated as more progress is made, so keep checking back every week or so until this part of the project is done and the walls and ceiling have been closed up with paneling.

We live in an area where choice of materials is limited, so we had to make a special trip to Mountain Home (about 50 miles west) to pick up the insulation board. Home Depot and Lowes are side by side there, but neither of them had what I would have preferred, Polyisocyanurate board, which has the best R factor. As always, we had to make do with what was available.

To complicate matters, our Haulmark cargo trailer (actually designed as a motorcycle trailer) was built with 1-1/4 inch steel ribs, rather than a more standard 1-1/2 inch. We could have bought insulation board in 1-1/2 inch thickness, but nothing is ever that easy. To get the thickness we needed I had to go with whatever they had in stock, and get a combination of 3/4-inch sheets and 1/2-inch sheets. We looked at the pink stuff first, but Home Depot only had one of the sizes we needed. So we went next door to Lowes and found that the blue sheets were a buck cheaper, and they had both sizes, so that's what we went with.

As I said in the previous post, some people may say I should have picked something different, but in this area, we have to go with what we can get. And insulation value is of minor concern, because we plan to travel with the good weather, south in the winter and north in the summer...or at least change elevations, which is easier to do in more mountainous terrain. Our need for insulation was as much for sound as anything else. If you have ever been inside a trailer during a heavy rain storm, or worse yet, hail...you understand.

Our trailer's straight sides are only 68 inches tall. Because the roof bows curve up after that, we have a good six feet of standing room, even near the sides, and that's plenty tall enough for us.

Our conversion van has all the seats in it, and the middle row won't fold down. We laid the electric couch/bed flat, and that provided six feet of length (up to the back of the middle row of seats) to lay anything flat in the van, so it worked out well. We needed nine sheets of both thicknesses of insulation, so I took my drywall T-square and a utility knife with us, and we cut all eighteen sheets to a six foot length. The nine 2-foot pieces were also laid flat in three layers on top of the larger sheets.

As you can see, I have an abundance of plywood pieces (with more lumber and trim on our rear deck), left over from my remodeling days in the four years before I retired. If you want to see some of my past projects, they are at http://hardyhandyman.blogspot.com, and that is yet another blog that I need to add more projects to.

What you see in the photo above will be used to cover cabinet frames and other things. Because we look at this project as temporary, we don't want to get too fancy, but still make it look nice. I'm not going to try to buy new matching paneling and build a lot of fancy hardwood cabinets. This trailer is going to get primed and painted a light color on the inside (maybe white). By doing so, I can use up all this scrap plywood without worrying about what matches. It will all look the same by the time I am done, and it will also be easy to fix in case of dents and dings. It's just more practical in all regards. Besides, the light interior (rather than wood paneling) will be much brighter and seem larger.

I had to straighten up this stack of paneling leaned against the right side of the trailer, and had just enough room to stack the insulation board against it. Now you see why I am doing one section at a time. There's not much floor space left until this stuff gets installed!

So now comes the blocking. I started in the front, on the ceiling. We will have two Fantastic fans, one at the front and one at the rear, so I framed the front one first, making sure to leave enough room around it for the trim. The ceiling light shown will eventually get replaced with an LED fixture, and it can be moved slightly when that time comes, but still, I wanted to leave enough room. Also, you can see the fiberglass front cap of the trailer, which is curved. I wanted to stay away from the rib on the roof where the metal roof joins to it.

The framing is slightly less than standard 2 x 2 size because of the 1-1/4-inch rib depth. Every piece of blocking has to be cut down to that depth in order to fit in the space. The steel ribs have to be drilled with a pilot hole before the screws can be installed. I'm using coated 2-1/2-inch deck screws which I pull off a strip of plastic, which was used with my Senco deck screw gun. You can buy similar screws in boxes.

Where the wood joints meet, I use wood glue to make sure they don't move, although I cut everything tight enough that they will stay in place even before the screws are installed.

This former motorcycle trailer had no plywood ceiling in it, and what blocking you see on the far right in the photo above was only "one by" boards, installed to give them something to strengthen the ceiling where they rounded the sheet metal roof. But they aren't thick enough to be flush with the inside of the rib, so they are worthless as far as inside attachments.

The front wall of the trailer was actually two pieces of plywood, with a joint down the middle. I could have done that on the ceiling, but a 4-foot width down the center works out just as well. The upper cabinets will cover the edge of the plywood in most places (except above the entry door and the head of the rear bunk). So I carefully measured to the center, and then 2-feet to either side, and snapped a chalk line where the edge of the plywood would be. After cutting the 2 x 4 pieces down to the size I needed (2-1/2" wide by 1-1/4" thick) and doing a little notching to clear existing roof screws and the curvature in the corners of the ribs, I made a mark 3/4-inch in from the edge, and placed that to align with the chalk line on the ribs. It takes a lot of trial and error cutting and fitting to get everything just right, but is worth it in the end, and there isn't really that many to do.

This is an ideal location, because the upper side cabinets will also be screwed into this blocking, and to the side walls, and the edge of the plywood will be covered by those cabinets, giving the ceiling a "one piece" appearance (except for the one end joint somewhere in the middle, since the trailer is 12 feet long). The curvature of the ceiling and front corners of the trailer will be covered with bent sheet metal, such as aluminum flashing material.

Because some of these "2 by" blocking pieces have to be toe-nailed at an angle, I have been using a special 1/8" by 6" long metal bit, that I eventually broke. Home Depot didn't have any, but I found them at Lowes, and bought three...which I proceeded to break the same afternoon that I brought them home! 

Darn!

No one around here has them, so I had to order some online, which I am waiting to arrive so I can go back to work on the blocking. Trying to drill at an angle into metal is quite tricky, even when going through a pilot guide hole in the wood. 

And you never want to drill at an angle toward the outer skin of of the trailer, or you take the chance of drilling through it! ALWAYS drill your pilot holes so that no matter how deep your screw goes, it won't go through the trailer skin!

Some holes can be drilled straight through, if you have room to get your drill and bit behind it, but still, use a center punch to keep your bit from wandering.

As of yesterday, all of the walls in the trailer have been insulated and the plywood re-installed. I removed the wall switch totally and those wires will be spliced together to make the light circuit hot all the time. The dome lights already have switches on them, and besides, I need to tap into those wires to provide power to the two Fantastic fans, which also have their own switches on them.

The only things that need to be insulated yet are the edges of the curved roof down both sides of the trailer, and the front cap area. The sides will be easy. I just need to score the back side of the insulation so it can be bent around the curve of the roof edge. The front cap will be the tricky part. It is curved with the roof, as well as around the front of the trailer, so nothing is straight on it. I can't just fill it with foam because there is wiring up there that has to remain accessible.

The plywood ceiling will have to be installed first, and even the front section of that must be cut in a curve and then bowed to the ceiling curvature. Before I install it, I will have to use spray adhesive to attach foam board to it in front of the last roof bow, as that is the only way to get the rigid board in there or to hold it in place. The same will have to be done with a removable filler panel that will attach to the front wall between the top plate of the wall and the ceiling, so as to make the wiring accessible. Also, that panel will have to have some backing behind the top of it to fasten it in place, so the ceiling will have to extend beyond the vertical plane of the wall so that I can glue and screw some 2 x 2 blocking to it in short sections. That's the only way to get around the double curvature. The wall panel will then screw into the blocking. All that is complex enough without trying to fit insulation behind it, too, but it has to be done that way.

In the process of everything that has been done so far, I have seen many things about this trailer that I would not want to see if I were buying a new one. But rather than get into naming all of the issues I have seen, I think it is more prudent to write a new post pointing out the things to watch for when buying a new (or used) trailer for the purpose of converting it to a camper. 

As I said, this post will be updated with more pictures and text as I can get the last of the blocking and insulation work done, but even if you forget to return here, I think you get the idea of what I am doing with the blocking. 

After that will come some wiring for the fans, and the ceiling will be ready for the new luan plywood sheets to cover it up. On the sidewalls, I re-used the existing 3/8ths plywood. It's going to get primed and painted anyway, so it saves money. But it had to be removed first, to block and insulate, and then put back on. After the ceiling and front wall are done, then I will start on the floor. It will get new luan underlayment plywood, and then we'll install new 1/8th inch thick commercial tile over it. That is solid vinyl tile in which the color goes all the way through it, and it is practically indestructible. After that. we'll start building the interior components.

So stick around. Make sure you click one of the links in the sidebar to follow on social media, RSS, or plain old email notifications, depending on which you prefer. Or, you can choose all three, to make sure you don't miss anything. I like choices, and yet I see so many bloggers fail to provide those choices. If you expect followers, you need all three types of subscriptions on your sites, People! 

So now that you see what I am doing, and why, what are your thoughts? C'mon...speak up!