Anchoring A Tiny House To The Trailer

Today I have a quick video that I wanted to get up before I start working on my Tiny House today.  It was pretty cold out this morning at 7am so I took advantage of needing to get a post up on the blog while it warms up a bit.  Many people have asked how do you anchor a Tiny House to the trailer so that it doesn’t come off while moving down the road or get lifted off during a storm.  This video will show my approach to this.  I actually upped the number of attachment points from what the plans called for after talking with my weld who has spent 30 years in construction trailer frames for mobile homes, RV’s, and trailers.  The important thing to note that I didn’t in the video is that the anchor points are aligned with the cross members of trailer which make it a lot stronger.


Anchoring the Tiny House

  1. I see that the Trailer already has a wood platform. how will you be preventing moisture from coming up and rotting out the floor? Is there some sort of metal sheeting below the wooden platform? or something like tyvek?

    • The flooring is made of pressure treated plywood and the top of it will be completely sealed, so the only moisture will be vapor evaporating from the ground, which will be very dry because its sheltered from above. The house is also elevated so there will be good air flow beneath to dry out any moisture that would find its way down there. When I get this in its final resting place I am planning on putting gravel pad to help any water to quickly drain.

  2. i am avidly following you and can’t wait for more photos or video.

  3. The concrete blocks you have your trailer leveled on are on their sides. They should be turned 90º do the openings ate at the top and bottom for strength. I know they are just there to level the trailer, but they can easily fail in the position they are in and through the who project out of whack.

    Looking forward to the build.

    • That’s a common mistake because people assume the flat side is what your load should be sitting on. I saw someone make this mistake setting up a single wide mobile home by themselves to save money. They had 4 6-ton hydraulic jacks on the blocks and were about 3 blocks high when things started going bad. When one stack started collapsing they ran a jack to there and when the weight was secured another stack started going. They were very lucky they had just enough jacks that day. They had to one by one fix each stack. Quite a few block broke on the 14’x66′ mobile which was spendy.
      They make a concrete pad for setting on top of the blocks.

  4. Exactly! The layers will go something like this. Trailer deck, metal flashing, 6 mil vapor barrier, treated wood framing filled with foam, then plywood subfloor.

    • “filled with foam” are you using spray foam insulation or foam board and caulking the gaps?

  5. Ryan
    Is your decking (below the framing) 2″ X 6″ or 2″ X 8″ ? This is pressure treated , right? Does this usually come with a trailer or does it have to be installed?

    • It comes with the trailer in most cases and is pressure treated. The size really is irrelevant.

  6. On the 5/8th lag bolts….what is your length?

    • Which ones are you asking about, the front ones, or the vertical welded ones?

  7. I don’t understand this… The c – thing on the back is supposed to hold the frame how? Amd how do the rebars hold the house? My level of current cluelessness makes me doubt my ability to build this 😛 I’ll keep plugging along

    • It is an anchor point where a 5/8ths threaded rod will be used to tie the floor framing to the trailer.

      No rebar here. You might want to check out the Tiny House Conference!

    • It’s the same concept as the 5/8″ anchor bolts they put around the perimeter of a concrete slab for a house. The bottom plate (2×4 or 2×6 wood) gets a corresponding hole drilled in it and the wall slides down onto the bolts and is secured with a nut and washer.

  8. Ryan,

    You’ve referenced welded galvanized threaded rods in your construction, and I would ask you to make a special point to talk about the dangers of welding galvanized material in the narrative of your videos. There are many do it yourselfers who have good intentions, but limited experience in construction, and you have the opportunity to help them avoid sickness and death by advising them of the dangers of “Metal Fume Fever.”

    In short – if you’re going to weld, heat, or forge galvanized material, please wear a respirator. Better yet – don’t do it at all. Substitute non-galvanized material when you know you’re going to be heating the material by welding it or cutting it with a torch.

    All health and safety comments aside, I think your documentation is great, and I enjoy your updates.

  9. Just some random thoughts here, and for those who have never had any experience in these things.

    Generally I have noted that those who are building their own tiny house on a trailer will have a pro welder or weld shop do the work to weld the threaded rods to the trailer frame. I would expect such professionals to know how to do this safely and without risk from the Galvanized fumes. There are a few who have done this themselves but usually only those who have experience doing it that I have read about.

    On the details of tying the floor framing to the trailer. This is part of an overall plan of tying the whole house to the trailer. The threaded rods that are welded to the trailer frame pass through the floor framing and are used to bolt the bottom plate of the walls to the trailer. Hurricane straps are then used in places around the walls to tie the studs to the bottom plate. And straps are then used at the top of the walls to tie the studs and top plate together to the roof rafters. There are also usually straps to tie the rafters together at the peak of the roof. This is all to keep the whole house on the trailer during transport as well as in high winds where ever the tiny house is finally set. Mobile home tie downs are used at the site to tie the whole construction to the ground.

    Keep in mind that a tiny house is not to be considered a home built RV. It is very different in construction and none that I have seen are designed to withstand regular travel as an RV is. A tiny house is first of all a house. Building it on a trailer is simply to take advantage of a loophole to get around the unrealistic and restrictive living space ordinances for permanent habitable dwellings. There are a few communities that have revised their ordinances to allow a tiny house to be built on a foundation, such as Spur, TX and Walsenburg, CO. Others are considering such a move. Check out the blog posts at for some info and links on these communities.

    Also, on concrete piers. I’ve lived in and leveled a mobile home years ago and had to remove the defective pier structure it originally set on and replace all the piers correctly. Yes, all concrete blocks should be set with the holes up to down and not sideways. There is no strength when they are set sideways. The first course of a pier should best be set on a solid concrete cap block, 16″x16″x4″ on the bottom. Then 2 blocks, holes up and down, are set side by side on that. The second course should be set the same except crossways to the first. IOW- first course is set north and south, second is set east and west to tie each layer together. And so on for each course. The pier should ideally be topped by another solid cap block if there is room. Then a wood block 6″ to 12″, or somewhere between, x2″x16″long should be set on top of that. If there is not room for the cap block then just use this wood block for the cap. Fine tune the level by using additional wood blocks and wedges, but not too many. Wood is highly recommended between the metal trailer frame and concrete since metal on concrete could cause problems. I had to set a mobile home at least twice this way (had it in one location and then moved it to another location) and assisted a friend with another. Never had any issues with going out of level this way and was very stable for a great many years.

  10. What’s the advantage of having the anchors welded to the trailer over drilling holes in trailer and putting lag bolts in from subfloor to trailer?

    • Every hole you drill compromises the integrity of the trailer

      • Ok, thanks Ryan! I am not too worried about that because the places I will be drilling do not impact the structural integrity of the Trailer. I had some extra beams welded on for this purpose.

      • True, thank you for raising that point. I am planning which way would be the most effective on a rehab rv trailor (I have been enjoying the work, gratifying!)

        • I’ve also seen blogs where they’ve welded lag bolts or threaded rods to the trailer and they have snapped off. If I can find the blog I’ll post it up on here.

  11. So cool guys really helpful info, trying to organise my trailer build and my metal frame to go on it so all of this made a lot of sence to me and I’m a woman so it was great to be educated on this part of the build

  12. Hi, great information. I hope you tell me more!

  13. Hi you video is a little shaky could you try to move slow ans easier to get it no so shaky please them we get a good steady long look,thanks great job 🙂

  14. hello, on the roofing section you mentioned “Ensure height stays under 13.5 feet”. Are you referring to the height of the house (from trailer to roof) or total height from ground level to the roof?

  15. Me and my girlfriend have huge but desperate dreams of building a tiny house. We dont have the budget to have it built, we are having to do it ourselves. We really want the tiny home to be mobile. But we are having trouble everywhere we turn. Could you possibly give me some advise on where to look for at least the trailer bed for the tiny house to build on?

  16. I am wanting to move 25.5 ft RV / tiny house to Oregon.
    Thinking of Gold Beach, Port Orford or Bandon.

    I see Bandon code says NON temporary RV is a mobile home or TRAILER HOUSE. What does that mean ? Can’t rent on private land without sewer ? I have living with OUR sewer for a year. Dig hole, bury.
    1. I have NO propane appliances, lines or tanks.
    2. All poly butyl REPLACED with 1/2 inch PED.
    3. Heatpump for heat ONLY, on rear bumper

    Allen P.

  17. I am putting 8 inch vinyl siding on both sides.
    Any problem going through Washington State or Oregon for MOVE only ?
    Thank you.

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