Dropped floor construction ideas

[danlott]

I am at the point where I need to build my dropped floors. I am starting to think that maybe I need to rethink how I build it. Here is a picture of what I have planned.





I plan on using 1/2" plywood for the sides and 1/2" plywood for the floor. I will use 1.5 x .75 for the joist on the dropped floor. Below that I would sandwich it with 1/4" plywood.

My concern is will this hold enough weight as designed? This with have to be able to hold the weight of possibly 2 people standing on it, say 400 lbs. The front area will only be for storage under a bed, so I am fairly sure that it will be fine for that, my concern is with the standing area.

What do you guys think, how is your dropped floors constructed, are they holding up well?

Dan

[terryjones1]

I am at the point where I need to build my dropped floors. I am starting to think that maybe I need to rethink how I build it. I plan on using 1/2" plywood for the sides and 1/2" plywood for the floor. I will use 1.5 x .75 for the joist on the dropped floor. Below that I would sandwich it with 1/4" plywood.

My concern is will this hold enough weight as designed? This with have to be able to hold the weight of possibly 2 people standing on it, say 400 lbs. The front area will only be for storage under a bed, so I am fairly sure that it will be fine for that, my concern is with the standing area.

What do you guys think, how is your dropped floors constructed, are they holding up well?

Dan

I used 1/2" plywood for the floor of the dropped floor.
I made the steel frame with a 7" drop at the dropped floor.
I used 1-1/2" x 1-1/2" x 1/8" steel angle iron, side to side accross the floor, approximately 18" appart (3 runs of approximately 74").
I welded the angle iron to the dropped frame.
The angle iron is plenty strong for two people (I weigh 230. My wife weighs considerly less).

[danlott]

I was hoping to not have to use angle iron, but I probably will have to use some metal to help reinforce the drop floor. I was thinking about using some metal straps in the shape of a "U" that would cradle the drop floor. I could screw the metal straps to the drop floor and main floor at various points. The straps would also sit on top of the frame crossmembers, but they would not be welded to the frame.

Something like this.



Dan

[CarlLaFong]

Dado the floor into the sides, like a drawer box. Use plenty of glue and screws and it should be just fine

[doug hodder]

Dan...I see you aren't doing a drop floor through the frame for the door. I really like the straight shot in and no step-over. On mine, I welded up some angle iron vertical pieces 1" and then the same material for across (under) the floor, a C channel like you are planning should be fine. I could get the angle easily. I figured where the bulk of the weight would be when standing at the galley and reinforced those members with a piece of the angle tying them all together. I also figured where my first step would always be when entering the trailer and put an angle iron cross member under that portion as well. I've had 3 people standing in mine...no problem. Flooring is 5/8" 7 ply material and used epoxy to glue it up. I also used some 3M VHB foam tape on top of the angle iron to minimize any potential squeeking...none yet. I have a couple of years on it now. Doug

[danlott]

Doug,

I like how you did your frame. Also not having to step in and down would be nice. The problem is I have already built the walls and floor. The frame is also finished, so I would have to change alot at this point to do something similar to what you did. I think the straps would probably be more than strong enough, but I could possibly weld some angle similar to how you did yours.

Dan

[cuyeda]

Steve Frederick built a dropped floor by having a steel rectangular pan welded together at the seams. The fabricator provided lip flanges that could fit over the frame members to be welded in place. The floor was then put on top, and lined the dropped floor pan with plywood. I can't find the picture, on his web page, but it may also be on his build CD.

If you absolutely need a picture, I can try to find it.

[danlott]

Cliff,

Thank you for reminding me about Steve's method. I do have his build CD, so I have that information. I have been planning and building this trailer for so long I think I have forgotten alot along the way.

Dan

[cuyeda]

I get it, I have been mentally planning a teardrop build also. With so many great ideas to borrow from others, it's hard to make the choices. My problem is that all these other trailer projects keep poppin' up ahead of my teardrop build. haha. I already collected various doors, window, lights, latches, etc etc... I will eventually get a round tuit. At the moment I am trying to figure out a dropped floor area to add a shower/toilet combo, then add various holding tanks that were not there before.

Good luck with your build, the planning stages look great!

[danlott]

After sound advice from everyone here and a slap of reality I was finally convinced to go with angle iron to help reinforce my drop floor. Here is a picture of the new supports.



Thanks to everyone for their advice.