What is my exterior wall Depth for screws

[re-pete]

I need some advice on maximum screw depth in the outside sidewalls and if the following sounds like a reasonable mounting plan. I'm fully open to suggestions.

I have a 2019 Bullet Ultralight Bunkhouse. I'm modifying the water pump containment between the left side of the bed and the outside wall. It's height (19-3/4") and depth (11") makes it difficult to get in and out and to make the bed on the left side. I realized that I can cut it down to a height of 13-1/8" and not interfere with the pump or the water lines. And, by beefing it up I can make it into a tall step. Anyway, it will involve re-attaching part of the frame to the outside wall, as it already was. Keystone did it with screws only. Because I'm cutting it down I'll be attaching it in a lower position on the sidewall. I have very little idea of what I'm attaching it to, so, I plan to use some type of construction adhesive and screws, but as I said, I'm not sure what length of screws to use nor exactly what it is that I'm screwing into. This is what I'm hoping one of you can tell me.

The other two sides were attached to the wall separating the front storage compartment and bed platform, with 1-1/2" staples. I'll do something similar. The inside of the sidewall appears to be some kind of thin panel probably a light weight paneling, with a vinyl veneer. Behind that I have no idea. My guess is a foam insulation and some kind of framing. What kind oof framing is unknown. The original pump containment frame was screwed to the outside wall, but I misplaced those screws and I didn't write down the measurement. The framing material I'll be using is mostly the same as Keystone used, 3/4" x 3/4" thick pine and fir. I'll also be using a some 3/4 x 3-1/2" wood and some 1-1/2" x 1-1/2" to make the step weight supporting.

I'll post some pictures of the process for anyone who might be interested in this mod. It's at a campground in Northern Virginia about 2 & 1/2 hours from our home so most likely I won't get this done until the after the new year possibly in the spring.

Here's a picture my floor plan for reference and another of my framing design which I mocked up in SketchUp.

Regards,
Pete

[dutchmensport]

Simple solution! Make the box and then, as you said you were going to use, attach it to the wall with Construction Adhesive (Liquid Nails) and be done with it. The "box" will never, never, never move and you run no risk of using screws that are too long.

[re-pete]

That does make perfect sense. I was worried that the framing might move, but clearly by anchoring the other two sides to their mounting surfaces with fasteners it will not.

Thank you,
Pete

[fourwalshes]

I like your idea!

[re-pete]

Thanks, my wife likes to sleep on that side. This will make it much easier for her to get in and out of bed. Plus, it will make it much easier to make the bed and get to the closet on that side of the bed.

[DAMILLER_SR]

I would stand by the door and just put my fingers together on the inside and outside, and you can generally gauge the distance

[re-pete]

Great suggestion. Thanks!

[GordKey22]

I just changed things as I went along. I did add sound proofing in the pump box and insulated it from the floor. I tried to make sure that none of the pipes or hardware were attached directly to the "wood?" of the trailer. (the pump noise had the knack of getting me really pissed off.)
Interesting to see how close the layout was. Mine is a 22KBSWE and 2018. file:///C:/Users/Owner/OneDrive/Desktop/Screenshot%202024-12-17%20151508.jpg

[re-pete]

Originally Posted by GordKey22

I just changed things as I went along. I did add sound proofing in the pump box and insulated it from the floor. I tried to make sure that none of the pipes or hardware were attached directly to the "wood?" of the trailer. (the pump noise had the knack of getting me really pissed off.)
Interesting to see how close the layout was. Mine is a 22KBSWE and 2018. file:///C:/Users/Owner/OneDrive/Desktop/Screenshot%202024-12-17%20151508.jpg

How well did that work? Did it quiet the pump sound? Unfortunately your picture didn't load.

[GordKey22]

Yes, for some reason the interesting parts of the picture would not show up. I will try again later, I probably have to shrink it or something.

It worked out really well.

We used our trailer for a season before I started doing anything to it. We found that the original orientation of the bed was a pain, for us. I cut a new piece of plywood and aligned it so that the 'head' of the bed is up against the wall that has the tv. We find it much easier to get in and out of bed this way.

The pump had to be released from the cloud of expansion foam that the factory used to hold it in place. I then used Sonopan that I purchased at the "Borg." ("Big Orange Retail Giant - Home Depot. Resistance is futile, you will be back")

When I replaced the pump I cut a piece of sono to fit at the bottom, I then added about ten pads, of the same material, which I stuck into place using acoustic sealer. I panelled all of the sides then mounted the pump onto another piece of sono, smaller than the actual size of the bottom, then glued it in with acoustic sealer. Cut a couple of pieces for the top, sized to fit into the rebates left when I built the sides of the enclosure.
I also made sure that all of the piping was sitting in the middle of the transit holes, an effort to keep any pump vibration from transferring to the trailer.

This also gave me a chance to add some USB A ports for charging in that area.

The pump is extremely quite now so I am happy. Was a real pain if someone used the toilet in the middle of the night. That thing woke me up every night for an entire season.

https://www.homedepot.ca/product/son...-in/1000441119

[re-pete]

GordKey22,

Sounds like some very useful mods. Thanks for providing so much detail and the material link at HD. If you ever get that picture sorted out I'd love to see it.

Happy Holidays!

Pete