Teardrops n Tiny Travel Trailers

Hello,
Looking for some help on how to build a woodie micro tiny house style trailer, LxWxH 11.15 x 6.2 x 7.6 peak.
The most important criteria is weight. I am limited to 1650 pounds all in. I want to keep the interior as clean and uncluttered as possible. Thinking about a fold down bed that rests just above the seating/eating/living area so i have multiple use of the same surface area.

Models i am looking at :





I have finished my floor, now need to attach it to the trailer. (Floorplan, metric)




What thickness foam would be appropriate. Thinking about 1.25 inch xps, with minimal wood bracing covered with 5/16 ply inside and out. I want to restrict wood framing to a minimum seeing the weight constraint.

Thanks for looking.

Thanks for sharing this. I have seen the tiny home in the upper photo. Have you seen the way he did the post framing to minimize lumber? I would also like to do something similar but on a larger scale so I will be watching your progress.

I assume you have ruled out poor man's fiberglass for the outside? If so, I am curious about what made you decide that way if you were willing?

The thing about 11/2 inch insulation is that it syncs up with using standard 2x2's for framing so that seems easiest.

Another possibility I have seen to diminish weight on tiny home on wheels is steel framing but then of course there is the complications of using steel versus wood.

Congratulations on getting started and good luck with the project!

Bill

Websites will be your best bet. Search "tiny house on wheels" and "tiny house" Sign up for any news letters etc. Keep a folder for photos of ideas that you like. Pics of floor plans can be free, they can be adjusted to your wants and needs.

Here is a start.
https://tinyhousetalk.com/how-they-foun ... tiny-home/
http://tinyhousenewsletter.com/

Yes, i read the how the builder used post and beam to reduce lumber.

Using mostly foam and ply, creating a sort of SIP, would reduce weight further.
The reason for epoxy/fibreglass over pmf is to preserve to wood look and the price is not that dissimilar on the total budget it seems.

I have built a couple of skin on frame kayaks, and i seem to have seen someone building a trailer that way as well. Not sure it would work with a micro tiny house, with such large panels to get the fabric tight.

I found a source of cheap lightweight poplar 4mm ply used mainly for pigeon-coops around here. I tested uncoated pieces it in a bucket of water for delamination and it remained solid.
The only issue i have with it is that the wood grain is very boring.

Would using thin shiplapped red cedar, laps epoxied and boards epoxied to the foam and ply on the inside create structurally sound panels ?

If i could get away with 20mm xps i would, to maximising the inner width fully.

The caravan i bought which provided the trailer, was already half demolished, used 1 inch bead board, 2.5mm inner ply and aluminium siding.

Living in the metric side of the world, so get your calculators out

dogcatcher wrote:Websites will be your best bet. Search "tiny house on wheels" and "tiny house" Sign up for any news letters etc. Keep a folder for photos of ideas that you like. Pics of floor plans can be free, they can be adjusted to your wants and needs.

Here is a start.
https://tinyhousetalk.com/how-they-foun ... tiny-home/
http://tinyhousenewsletter.com/

Thanks....i can't take any more looking on that site Too many ideas, too little space

woodie72 wrote:
...........Would using thin shiplapped red cedar, laps epoxied and boards epoxied to the foam and ply on the inside create structurally sound panels ?...........
:

I would recommend against that. The cedar will expand and contract with moisture unless completely encapsulated probably causing the glue joints to fail eventually. Successfully gluing anything to foam means maximizing the gluing surface area.

If you are going to fiberglass, I take a look at thin marine ply. I can get 3mm Meranti or Okume over here and they are both beautiful under fiberglass.

20mm foam might be good enough if your lamination is top notch. We're probably talking vacuum bagging on a really flat work table.

Pmullen503 wrote:

woodie72 wrote:
...........Would using thin shiplapped red cedar, laps epoxied and boards epoxied to the foam and ply on the inside create structurally sound panels ?...........
:

I would recommend against that. The cedar will expand and contract with moisture unless completely encapsulated probably causing the glue joints to fail eventually. Successfully gluing anything to foam means maximizing the gluing surface area.

If you are going to fiberglass, I take a look at thin marine ply. I can get 3mm Meranti or Okume over here and they are both beautiful under fiberglass.

20mm foam might be good enough if your lamination is top notch. We're probably talking vacuum bagging on a really flat work table.

I have worked with okoume marine ply in stitch and glue kayaks before and it can be nicely finished with a stain before epoxy.

The problem where i live is i can't get 3mm. The 4mm i can get costs over 4 times as much as what i have found close-by and it's a bit heavier.

I was thinking of cutting the plywood in strips, say 5 to 6 inches and putting a shiplap and a small chamfer on them to create a boarded appearance and to facilitate a good bond. Vaccuum bagging is not a possibility.

I have also have been thinking about using 2mm birch ply, just for the weight saving. On a single side it would save me 44 pounds approximately. Every bit counts, right ?

I know pmf would even save me more weight, but i don't like the finish much and to resell it if opportunity presents itself, pmf is an unknown for the vast majority.

Now for the inside i would like to use cork as a final finish, so there i could maybe go pmf with woodglue and finish off with cork ?

Another thing i rarely see in the forum is a dpc, damp proof course, between the trailer and the floor.

For sheds or small cabins over here i sometimes see left-over roofing material used, as a cheap alternative.

I bought some cheap 3mm rubber flooring material to glue on the trailer before attaching my sandwich floor, mainly to prevent rubbing between metal and plywood. As an added benefit, vibrations will be dampened slightly i hope.

Working on the walls right now and have a question for the wall to floor joint.

I am using 30mm foam, routed 10mm slots every 15cm for attaching thin wood strips. After this the whole gets fiberglassed inside and out. On the inside i am thinking of using cork glued to the fiberglass.




A question : Is there a reason why i haven't seen the use of a cleat that is epoxy glued and screwed to the underside of the floor, extending to support the wall and this joint, wall, cleat and floor (1 1/2 sandwich) ? There will be glass tape from the bottom 2 or 3 inches going around the cleat and to the underside of the floor.

Lacking feedback i went ahead and shaped the cleats.

They will be epoxied and screwed to the floor. The side wooden slats will go to the bottom, overlapping the cleats, rounded over and then fiberglass will wrap around the sides, the cleats and will extend to the bottom of the floor. Shaped so the glass nicely follow the curves. Cleats extend 2 inches under the floor. Foam will be poly glued to the side of the floor and to the cleats. I will add a wooden batten on the bottom of the foam, so glued up will be easier, no need for clamping straps.

I believe there is no need to add a batten to the foam. Depending on the
type of glue used, there may still be need to use clamping regardless of
batten or none. Standard wood glue will stick to prepped foam with a
longer curing time.

Actual best approach is more dependent on how you are attaching your
outside skin?

pchast wrote:I believe there is no need to add a batten to the foam. Depending on the
type of glue used, there may still be need to use clamping regardless of
batten or none. Standard wood glue will stick to prepped foam with a
longer curing time.

Actual best approach is more dependent on how you are attaching your
outside skin?

I will be using an equivalent to gorilla polyurethane construction adhesive. My thinking was if i can use a couple of screws to pull the panels to the cleat, it might be easier to clamp the big 11 by 6 feet approximately panels with straps.

Come to think of it, would a long batten screwed from the outside to the floor suffice for holding the panels to the frame and stop them moving up while the glue cures

The outside skin will consist of wooden slats, like cove/bead kayak construction, and then covered with fiberglass, mimicking the sock like the foam/canvas method.

A sip or stressed skin panel relies on a continuous skin - like plywood - for tensile and compressive strength, and resistance to racking. Slats or clap boards will not be close to a monolithic skin.

Doesn't bead and cove strips/strip planking under fiberglass create a continues skin ?

The tongue and groove has no shear strength so just the fibreglass. Perhaps 3 or 4 or more layers of glass and resin would come close to a piece of ply. Stability perpendicular to grain will be iffy because of changes from humidity, especially outside. No tensile strength in t&g. Just pulls apart.

Look at sips. Continous one piece skin. The skin is subject to tension and compression parallel to the panel.

Just like a hollow door with honeycomb, or an I beam or a tji (wood joist) all the stress is in the flanges or skin.