Forum Discussion
Dave_Pete
Jan 02, 2018Explorer II
Today: Framing out the bathroom back-wall and filling in with foam board. Fastening the shower pan securely.
With the new year now upon us, we move into the final build of the camper, here in the right-rear section of the floor plan - the bathroom.
Now whether it's hot outside and you're trying to keep it cooler in the camper, or if it's freezing out there and you're trying to stay warm, it's important to keep the bathroom in the comfort zone. Who wants to crawl out of the bed in the middle of the night and hang out near the ice-box in the back corner of the bathroom? Not me. No sir!
And right from the get-go, we have been thinking about that. Okay, well - build requirements helped us think about that. Okay, so build requirements FORCED us to consider filling up dead space with something. There.
We chose insulation - where possible.
What was the build requirement? The shower pan dimension. Maybe you remember back when the space was just a closet, with a false floor, and a stack of shelves. Out came the shelves and the wall surfaces all got rebuilt. Let's talk about those.
The wall that includes the door - simply a 1/8" paneling board over 1 by framing. No need for insulation because it's an interior wall. Then there is the common wall, another interior segment between the dinette and the bathroom with a similar construction to the door wall.
But now the camper back wall (in essence the bathroom side wall) and the camper propane cabinet (what is the bathroom BACK wall), both are exterior walls. So when I had to make the original closet slightly smaller to fit the shower pan dimension, I ended up with an extra 3/4" to fill on the camper back wall, and about 1 3/4" on the propane cabinet common wall. So the propane cabinet was two surfaces of 1/2" plywood sandwiching some 3/4" foam board.
The exception is a non-insulated and 1/2" plywood countertop underlayment, the top of the propane cabinet, and I have an idea for that - see? We'll get to that someday.
The walls themselves were already built, but I had the camper back wall still to finish, and it has the window too!
After re-evaluating a long-ago began "false-start", I pulled out a couple of 3/4" plywood spacer boards and added in 3/4" (1 bys) solid pine/fir boards - as the plywood is 1/32" thinner and you could tell, alongside the foam board edges. With the replacement boards in place I screwed down the shower pan.
Like this.

Note in the above photo, the wood build around a small segment of camper wing, there at the lower left side. And note the spacer firring on the lower right.
I used the screws like a flange, to keep from putting a hole in the pan plastic and risking cracks and stuff.


The front edge will receive a different treatment, and an edge finish, after I figure out what I want to do there.

Here's more of the back wall framing, along with the lower insulation board. The top board is placed at a level where a big, bony knee might strike. I will be covering the foam board with a thin plastic surfacing material and I didn't want to strike it with a knee and leave a visual dimple in the wall surface, thus the board to absorb an impact.

And then there is the window. My window style uses an interior screen and finish framing which juts into the room. As it turns out, the jut is about 3/4" and a little more. Perfect. Frame it out, and seal it up right at a later time.

Stray shower spray near the window will go to the bottom, where the window has two weep holes to the outside, for condensation, if we can keep the holes from freezing over.
The rest of the window region will be sealed similar to how I sealed the stove vent wall hole - with a sort of smeared caulking. And the screen frame to the window frame itself, with some sort of closed cell foam rope caulking type stuff. Or what we in the "bidness" call SSCCFRCTS.

Now to cut the foam board into the odd shape of the space. This is the lower.

And the upper.

And similarly on the opposing side, the same need (for the plastic surfacing, not any foam there).
Lower.

And upper.

Way back ago, after one Christmas Past (not this year - it was like a long time ago), I secured an end roll of Christmas wrapping paper from DW and templated the wall curve onto the paper. I used this paper for cutting the foam insulation pieces for the back wall. It worked. But it wasn't exact enough for the plastic wall surfaces. That required a new thing. Here's the insulation - post cutting.

Note it is all square cuts, except there at the top left where the roof curve begins a little.
And then I did the top segment of foam. Two pics.


And with that - I was all firred out. Flat surfaces. Ready for wall finish.
Over the years I've considered many different types of surface material, including paint-on (rubber roof or something). In the end, I decided on using that thin plastic bathroom/shower surfacing stuff. Flexible for the non-flat surfaces. The instruction sticker on it said not for use in RVs, so I used it.
But how to secure it? How to cut the curves? How to finish the corners? We'll start into that more tomorrow.
With the new year now upon us, we move into the final build of the camper, here in the right-rear section of the floor plan - the bathroom.
Now whether it's hot outside and you're trying to keep it cooler in the camper, or if it's freezing out there and you're trying to stay warm, it's important to keep the bathroom in the comfort zone. Who wants to crawl out of the bed in the middle of the night and hang out near the ice-box in the back corner of the bathroom? Not me. No sir!
And right from the get-go, we have been thinking about that. Okay, well - build requirements helped us think about that. Okay, so build requirements FORCED us to consider filling up dead space with something. There.
We chose insulation - where possible.
What was the build requirement? The shower pan dimension. Maybe you remember back when the space was just a closet, with a false floor, and a stack of shelves. Out came the shelves and the wall surfaces all got rebuilt. Let's talk about those.
The wall that includes the door - simply a 1/8" paneling board over 1 by framing. No need for insulation because it's an interior wall. Then there is the common wall, another interior segment between the dinette and the bathroom with a similar construction to the door wall.
But now the camper back wall (in essence the bathroom side wall) and the camper propane cabinet (what is the bathroom BACK wall), both are exterior walls. So when I had to make the original closet slightly smaller to fit the shower pan dimension, I ended up with an extra 3/4" to fill on the camper back wall, and about 1 3/4" on the propane cabinet common wall. So the propane cabinet was two surfaces of 1/2" plywood sandwiching some 3/4" foam board.
The exception is a non-insulated and 1/2" plywood countertop underlayment, the top of the propane cabinet, and I have an idea for that - see? We'll get to that someday.
The walls themselves were already built, but I had the camper back wall still to finish, and it has the window too!
After re-evaluating a long-ago began "false-start", I pulled out a couple of 3/4" plywood spacer boards and added in 3/4" (1 bys) solid pine/fir boards - as the plywood is 1/32" thinner and you could tell, alongside the foam board edges. With the replacement boards in place I screwed down the shower pan.
Like this.

Note in the above photo, the wood build around a small segment of camper wing, there at the lower left side. And note the spacer firring on the lower right.
I used the screws like a flange, to keep from putting a hole in the pan plastic and risking cracks and stuff.


The front edge will receive a different treatment, and an edge finish, after I figure out what I want to do there.

Here's more of the back wall framing, along with the lower insulation board. The top board is placed at a level where a big, bony knee might strike. I will be covering the foam board with a thin plastic surfacing material and I didn't want to strike it with a knee and leave a visual dimple in the wall surface, thus the board to absorb an impact.

And then there is the window. My window style uses an interior screen and finish framing which juts into the room. As it turns out, the jut is about 3/4" and a little more. Perfect. Frame it out, and seal it up right at a later time.

Stray shower spray near the window will go to the bottom, where the window has two weep holes to the outside, for condensation, if we can keep the holes from freezing over.
The rest of the window region will be sealed similar to how I sealed the stove vent wall hole - with a sort of smeared caulking. And the screen frame to the window frame itself, with some sort of closed cell foam rope caulking type stuff. Or what we in the "bidness" call SSCCFRCTS.

Now to cut the foam board into the odd shape of the space. This is the lower.

And the upper.

And similarly on the opposing side, the same need (for the plastic surfacing, not any foam there).
Lower.

And upper.

Way back ago, after one Christmas Past (not this year - it was like a long time ago), I secured an end roll of Christmas wrapping paper from DW and templated the wall curve onto the paper. I used this paper for cutting the foam insulation pieces for the back wall. It worked. But it wasn't exact enough for the plastic wall surfaces. That required a new thing. Here's the insulation - post cutting.

Note it is all square cuts, except there at the top left where the roof curve begins a little.
And then I did the top segment of foam. Two pics.


And with that - I was all firred out. Flat surfaces. Ready for wall finish.
Over the years I've considered many different types of surface material, including paint-on (rubber roof or something). In the end, I decided on using that thin plastic bathroom/shower surfacing stuff. Flexible for the non-flat surfaces. The instruction sticker on it said not for use in RVs, so I used it.
But how to secure it? How to cut the curves? How to finish the corners? We'll start into that more tomorrow.
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