So you want to start building your tiny house, and like any house, the first thing you have to think about is the foundation. For tiny houses on wheels, the foundation is the trailer. Getting the right trailer for your needs is essential towards building a tiny house you will love, so the first decisions to make are your trailer’s dimensions.

What should be the size of your tiny house trailer? To answer this, a tiny house owner has to consider the road limits of their area, as well as the size of tiny house they would like. The average trailer size dimensions for a tiny house trailer are 20 to 24 feet long, and 90 inches wide.

In this article, we will discuss the road limits of a tiny house trailer, the lower ends and higher ends of the possible dimensions (and what this means for your tiny home), and the costs you can expect for different tiny house trailer sizes.

Road Limits and Legal Issues

tiny house on the road

One fact that surprises new tiny home owners is that there is no national standard for size dimensions across the United States. While there is a National Highway Traffic Safety Administration, the rules for sizes are decided by each individual state.

Fortunately, the standards for trailer width and height across states are close enough that you won’t have to worry about it that much when driving across the country. Lengths do vary quite a bit, but as long as you keep your tiny house trailer to an average size, you won’t run into much trouble.

The most common dimension rules for trailers are as follows:

  • Total length: 65’ (excluding bumpers)
  • Trailer length: 40-50’
  • Motor home length: 45’
  • Width: 8’6” (with some states giving an extra 3-6 inches for safety equipment and other gear)
  • Height: 13’6” (this height is from the pavement to the highest-reaching element connected to the house)

To check the specifics of your state/s, we’ve prepared a chart with each state’s specific trailer dimension limits (information taken from the AAA Digest of Motor Laws):

StateTotal LengthTrailer LengthMotor Home LengthWidthHeight
Alabama57’28’6”45’8’6”13’6”
Alaska75’53’45’8’6”15’
Arizona65’28.5’45’8’6”13’6”
Arkansas53’6”28’40’8’6”13’6”
California65’ – 75’28’6”40’8’6”13’6”
Colorado75’45’45’8’6”14’6”
Connecticut65’40’40’8’6”13’6”
Delaware60’ (65’ with tow)40’45’8’6” for trailers, 8’ for motor homes13’6”
District of Columbia55’40’40’8’ (8’6” on certain roads)13’6”
Florida65’48’40’8’6”13’6”
Georgia100’53’Not specified8’6”13’6” – 14’
Hawaii65’45’45’9’14’
Idaho75’48’45’8’6”14’
Illinois60’53’45’8’6”13’6”
Indiana60’28’6”45’8’6”13’6”
Iowa65’53’ (45’ if travel trailer)45’8’6”13’6”
Kansas65’Not specified45’8’6”14’
Kentucky65’45’45’8’6”13’6”
Louisiana65’30’45’8’6”13’6”
Maine65’48’45’8’6”13’6”
Maryland55’ (65’ if travel trailer)35’40’ (45’ for interstates)8’6”13’6”
Massachusetts65’33’45’8’6”13’6”
Michigan65’28’6”45’8’6”13’6”
Minnesota75’45’45’8’6”13’6”
MississippiNot specified53’45’8’6”13’6”
Missouri65’45’45’8’6”13’6” – 14’
Montana65’Not specified55’8’6”14’
Nebraska65’40’40’8’6”14’6”
Nevada70’Not specifiedNot specified8’6”14’
New Hampshire53’Not specified45’8’6”13’6”
New Jersey65’53’45’8’6”13’6”
New Mexico65’40’45’8’14’
New York60’48’40’8’13’6”
North Carolina60’40’45’8’6”13’6”
North Dakota75’53’50’8’6”14’
Ohio65’Not specified45’8’6”13’6”
Oklahoma65’40’40’8’6”13’6”
Oregon65’40’45’8’6”14’
Pennsylvania65’53’45’8’6”13’6”
Rhode IslandNot specified40’45’8’6”13’6”
South Carolina53’40’45’8’6”13’6”
South DakotaNot specified45’45’8’6”14’
TennesseeNot specifiedNot specifiedNot specified8’13’6”
Texas65’28’6”Not specified8’14’
Utah65’53’65’8’6”14’
Vermont75’Not specified56’8’6”13’6”
Virginia65’28’6”45’8’6”13’6”
Washington75’Not specified40’8’6”14’
West Virginia65’40’45’8’6”13’6”
Wisconsin70’48’45’8’6”13’6”
Wyoming85’60’60’8’6”14’

Figuring Out the Size of Your Tiny House Trailer

Now that you understand the legal size limits of a tiny house trailer, it’s time to figure out the size that you want. Let’s start by understanding the general size of a tiny house trailer, as illustrated in this image:

Source: https://www.tinyhomebuilders.com/help/what-are-the-parts-and-dimensions-of-a-tiny-house-trailer

Length

Quick Answer: First decide your type of trailer, as this will factor in on the length. Shortest length is 12’, average is 20’-24’, and the longest trailers are generally 40’.

The first factor in determining the length of your tiny house trailer is deciding what type of trailer to get. There are four popular options for tiny house trailers, and these are:

  • The Deck-Between Trailer: In which the flatbed rests between the wheel wells of the trailer. This means that the bed cannot be wider than the wheels; while you sacrifice width, you make up for it with more height to work with, as the bed can sit lower to the ground.
  • The Deck-Over Trailer: In which the flatbed rests above the wheels. This allows the flatbed to be 8’ in width, although you sacrifice the height your tiny house can reach.
  • Dovetail: This can be either deck-between or deck-over, with the caveat of having a ‘dovetail’ at the rear, or a piece that is tilted down. This makes loading and unloading easier.
  • Gooseneck: Similar to the dovetail, it can be a deck-over or deck-between trailer, but it has a special hitch that reaches up, such as a gooseneck. The benefit of gooseneck trailers is that you can often build additional space over the area of the gooseneck, as they can be built with an extra platform.

Most tiny house trailers are normal deck-between trailers or deck-over trailers (depending on whether you want more height or more width for your home), with no dovetail or gooseneck. When determining your length, think of the flatbed as the flooring of your home, and how long you would like it to be.

The shortest length for a tiny house trailer would be roughly 12 feet, with an average at 20-24 feet (the average tiny house trailer used to be 12-16 feet, but they have since grown with their increased popularity).

Larger tiny houses can go up to 32 feet and even 40 feet, with some tiny houses extending to 45-47 feet if they have a gooseneck to reach over the trailer. However, remember that if you choose a length greater than 24 feet, you will require additional tires and axles.

Trailer Axle Weights

Quick Answer: Depends on the length of your trailer, from 2 axles at 5200lbs each to 3axles at 7000lbs each.

What axle weights do you need for your trailer? Weights can be a headache when talking about tiny house trailers, but the most important thing to make sure is that your axles can carry the weight of your tiny house. The weights of your axles are important, as these will determine whether your trailer will buckle or not once the house is built.

With most trailer builders, the recommended weights for axles for the different capacities are as follows:

Trailer Size (Length)Trailer CapacityAxle Weight
20 feet and shorter< 10,000 lbs2 axles, 4000-5000 lbs each
20 – 30 feet< 15,000 lbs2 axles, 5000-6000 lbs each
30 – 40+ feet< 21,000 lbs3 axles, 6000-7000 lbs each

Width

Quick Answer: 7’6” or 90”, giving you 6 inches on either side for house overhang.

What deck width should you choose for your tiny house trailer? Plenty of new tiny house owners want to go as wide as possible, and that’s understandable; your trailer is essentially the floor of your tiny house, and going wider means having more space. But you have to understand what that means, especially when dealing with the average road limit of 8’6”, or 102”.

Some states will pin you at a strict 8’6”, while other states will give you 3-6 extra inches for safety equipment and other appurtenances (meaning 1.5-3 extra inches on each side). So while you might think to just build the trailer width to 8’6”, you also have to consider things like your tiny house’s window trim, the roof overhang, the outside siding and sheathing, and everything else that pokes or hangs outward.

If built on a 8’6” trailer, most tiny houses would be breaking the road limit rules without even realizing it. If you insist on a 8’6” or 102” trailer, building your tiny house will require more careful planning.

This is why a lot of tiny house trailer builders offer a standard size of 90” instead of 102”, because then you can have 6 more inches on either side for everything on the sides of your tiny house. Most tiny houses actually have a base width that ranges from 7’6” to 7’10” (90” to 92”); after adding up siding materials and eaves or overhangs, this usually ends up at an even 8’6”.

Cost

new trailer

Quick Answer: Price most depends on length of trailer. $500 - $1500 for used; $3000 - $8000 if new and/or customized.

The cost of your tiny house trailer will depend on a number of things, including:

  • Whether it’s used or new
  • When it was built
  • If new, if bought off the lot or custom-made
  • The type of trailer (goosenecks typically cost the most)
  • Any custom modifications
  • The length of the trailer

We’ve taken a look at the most common places to acquire tiny house trailers and this is what we’ve found:

  • Used Trailers: On Craigslist or straight from the used trailer lot, prices can range from $500 to $1500
  • New Trailers (Bought straight from dealer): Depends on the length and type, but can cost an average of:
    • 12’ - 16’: $3000 - $4000
    • 16’ - 24’: $4000 - $6000
    • 24’ - 40’: $6000 - $8000
  • New Trailers (Custom-made from builder): Depends on the length, type, and expertise of builder, similar costs of new trailers, but with certain possible upgrades, such as:
    • +$2000 if gooseneck with platform
    • +$250 - $800 if specialized axles
    • +$300 if upgraded to 102” width
    • +$200 if upgraded with extreme hitch lock

Other Common Trailer Size Concerns

What is the max size for tiny house trailers without a permit?

It’s a common myth that you can get away with not securing a building permit if you keep your house below a certain minimum size. But this isn’t true – it doesn’t matter if something you build is 10 square feet or 10,000 square feet; the law states that if your structure has personal property, it is technically considered a dwelling, and dwellings require building permits.

Simply put, there is no max size for tiny house trailers without a permit. All tiny houses have to follow the same standards.

My tiny house isn’t a dwelling; it’s an RV or mobile home.

Again, it’s a common myth that you don’t have to think about certain size requirements and permit needs if your tiny home is registered as an RV or mobile home, but again, this isn’t exactly true. Your tiny home must be built by a certified manufacturer of mobile homes or RVs, or you yourself have to become certified, involving a tight inspection procedure.

If you say you are simply camping in your tiny home, you will run into another host of legal issues, such as a 2 to 30-day limit on camping on a designated camp zone before having to move.

How high off the ground is the typical trailer flatbed?

This can vary depending on the builder, but most trailer flatbeds built for tiny houses are typically low, ranging from 20” to 24” off the ground. This gives tiny house owners around 11’ to 11’6” of height to build.

If you want more height to maximize headroom (meaning a lower flatbed), you can choose the deck-between trailer, as the floor is more deeply integrated into the flatbed. For more space, optional drop axles can cut around 3-4 inches of height.

Buy Or Make the Tiny House Trailer You Need

Remember: the tiny house lifestyle is all about your choices and your needs. When shopping around for a tiny house trailer, don’t just stop at the first convenient trailer option you find. Ask yourself: does this trailer fit what I want my tiny house to be?

Your trailer is your foundation, and choosing the perfect foundation is the first step towards loving your tiny house.

About Us

Manuela and Ivan from Tiny House Bloom

Hey, there! We're Ivan and Manuela from Croatia, and we're crazy about tiny houses. We don't own one (yet).

This website is a result of our passion to share all the knowledge, photos, tips and tricks that we were able to learn while studying everything possible about the tiny house movement.