Toy hauler and fifth wheel carport sizing guide: height, width, and roof style for oversized RVs

People often toss around the word "gauge" when discussing metal buildings, but few stop to consider what it really means. For steel, its gauge is a system of determining how thick it is. The smaller the number, the thicker the material.

What Is Gauge?

Most metal buildings utilize 14-gauge steel for their framing. It’s light, sturdy, and can hold its own in most scenarios. However, some environments with higher wind speeds and snowfall demand thicker 12-gauge framing to carry the load and pass local building requirements.

And while you might not notice much of a difference in performance at first, that beefier framing makes it a lot harder for nature to bend or twist your structure out of shape.

Key Highlights

• 12-gauge = thicker and stronger
• 14-gauge = good for most small to mid-size builds
• Lower gauge = better wind and snow performance
• 12-gauge holds shape longer under stress
• Often comes with a better warranty
• Price bump is small compared to the upgrade in strength

Steel Gauge Chart

Gauge	Inches	Millimeters
8	0.164 in	4.17 mm
10	0.135 in	3.43 mm
12	0.105 in	2.67 mm
14	0.075 in	1.90 mm
16	0.060 in	1.52 mm
18	0.048 in	1.21 mm
20	0.036 in	0.91 mm
22	0.030 in	0.76 mm
24	0.024 in	0.61 mm
26	0.018 in	0.46 mm
28	0.015 in	0.38 mm
30	0.012 in	0.30 mm

How Gauge Impacts Loads

Thicker framing doesn’t just sound tougher. It is tougher. Heavier steel stands up better to snow buildup, hard gusts, and the added stress from longer spans.

Engineers run the numbers for wind and snow loads based on ASCE 7 standards. Using this system, buildings can be rated for anywhere from 115 to 170 mph winds and 20–60 psf snow loads.

The local requirements for wind and snow loads depend on location, open exposure, and roof pitch. For example, a building sitting on a hill or near the coast deals with more pressure than one behind trees.

Upgrading to 12-Gauge Framing

At what point should you consider upgrading?

• High Wind Speeds

If your metal building will sit in an area with high wind speed calculations, you may need to upgrade to thicker framing to prevent swaying or failure.

• Heavy Snow Regions:

If you expect to see your fair share of deep snows this winter, upgrading your framing thickness is a smart move.

• Longer, Bigger Buildings:

Longer spans put more stress on the frame of your pre-engineered metal building.

• Certification Needs

Higher wind or snow ratings often call for thicker 12-gauge.

• Lower Maintenance:

Thicker steel can last longer and require fewer repairs over the course of its life.

Cost and Warranty Changes with Framing Upgrades

You can expect a small price increase when you upgrade from 14-gauge to 12-gauge framing. You pay for thicker steel, heavier anchors, and reinforced braces to match it. Usually, you’re looking at around 10–15% more on the framing side.

However, that extra spend often gets you a longer rust-through warranty, sometimes 25 years instead of 20. The thicker galvanizing takes longer to wear down, especially in damp or coastal areas.

So, while the up-front cost stings a little, you’re getting fewer repairs, less movement, and a frame that won’t quit early. In the long run, it’s usually worth every bit.

Frequently Asked Questions about Framing Gauges for Metal Buildings

Do you have questions about framing gauge, and which thickness is best for you? Below, we’ve answered some of the questions we see on this subject the most:

Is 12-GA stronger than 14-GA?

Answer: Yeah. It’s thicker, heavier, and stiffer under load.

What’s the real thickness difference?

Answer: 12-ga steel is about 0.1046 inches thick, while 14-ga runs around 0.0747 in.

Does 12-GA automatically mean better wind or snow ratings?

Answer: Not by itself. The full design, including anchors, trusses, and layout, plays a role. But thicker framing helps you hit higher numbers.

Does the 20-year rust warranty only cover 12-GA?

Answer: Usually, the heavier gauge gets longer coverage. Some 14-ga options still offer 20 years, but 12-ga often goes a few years beyond that.

Most carports you see online? They’re built with a pickup truck in mind. Maybe a small camper. That’s not what you’re dealing with. Toy haulers and fifth wheels live in a different category entirely. Taller. Longer. Wider once the slides come out. And if you size your carport like it’s a basic RV, you’ll find out pretty quickly that it doesn’t work.

We’ve seen people scrape AC units backing in. We’ve seen slides hit posts. Neither one is a cheap lesson. So, instead of guessing, here’s how to think through it the right way—height, width, length, and roof style.

Key Sizing Facts

• Most rigs land somewhere between 13' and 14'6" tall
• You’ll want at least 18–24 inches of extra clearance above that
• That usually puts you at 14' minimum leg height, with 16' being safer
• Base RV width is around 8' to 8'6", but slides can push that to 12'–15'+
• Plan for 2–3 feet of space on each side
• Take your rig and add 4–6 feet for length
• For roof style, vertical is almost always the better choice

That’s the snapshot. Now let’s slow it down and make sure nothing gets missed.

Need a quote for a taller RV cover? Start with our 3D metal building estimator to size your height, width, roof style, colors, and options before you request pricing.

Why “standard size” doesn’t cut it here

An 18x20 with a 7-foot leg height works great for a sedan. Not for a 40-foot toy hauler that’s pushing 14 feet in height. Most modern toy haulers run mid-30s to low-40s in length, and they’re tall.

Fifth wheels sit right there too, except they’ve got a raised front section that adds even more height up top. And then you factor in slides. Once those are out, the width jumps fast.

If the structure isn’t sized for all of that, something gives. Usually it’s clearance.

Shopping for oversized RV coverage? Explore RV carports built for taller rigs and compare standard layouts before you finalize your custom size.

How tall does your RV carport need to be?

People tend to look up their RV specs and stop there. That number is only part of the story.

Fifth wheels

You’ll usually see listed heights between 13' and 14'6". But that doesn’t include everything sitting on the roof. AC units, vents, satellite dishes add inches. Sometimes more than you expect. By the time you account for that, you’re realistically needing 14' to 15'+ of clearance, not just the listed number.

That’s why:

• 14' leg height = workable
• 16' = more comfortable, especially for taller rigs

Want help measuring before you order? Read our RV carport height guide to measure true RV height, roof accessories, and usable clearance.

Toy haulers

The rear garage section can bump the height slightly, and then people add racks, panels, or other gear on top. Most fall in the 13'6" to 14'2" range, but again, that’s not the full picture.

If you’re anywhere near that upper end, don’t squeeze it. Go taller.

One thing you don’t want to learn the hard way

Clearance issues don’t show up on paper. They show up when you’re backing in, slightly off-angle, with wind pushing the rig.

How wide does your RV carport need to be?

If your RV had no slides, this would be easy. But it does. A single slide can add 3 to 4 feet. Two slides? Now you’re looking at something that can hit 14–15 feet wide when fully opened.

So the real question becomes: Are you storing it with slides in, or using it under the carport? Because that changes everything.

• Slides in → you can stay around 18'–20' width
• Slides out → now you’re realistically in the 24'–26' range, sometimes more

And beyond just fitting the structure, think about usability. You want space to walk, open compartments, move around without turning sideways. A tight fit gets old fast.

Need a wider cover for slide-outs? Browse custom metal carports to compare wider carport options, roof styles, and add-ons.

How long should your RV carport be?

Take your rig's total length (bumper to hitch or tongue) and add 4' to 6'. That extra room lets you pull forward far enough that the rear of the rig is fully covered, without the front hitch poking out the other end.

A 40-foot toy hauler needs a carport at least 44 to 46 feet long. A 36-foot fifth wheel needs at least 40 to 42 feet. If you're in a snowy climate and want to walk around the back of the rig without stepping out from under the cover, add 8' instead of 4'.

On the front end, the fifth wheel kingpin and the truck hitched to it will extend beyond your rig's listed length when the truck is connected. If you're storing the truck-and-trailer as a unit, measure the combined length before you order.

Looking for a long RV carport example? View this 30x45x12 RV Carport for an oversized layout with vertical roofing and 1,350 sq. ft. of coverage.

A simple sizing table to start from

RV Type	Height Range	Leg Height	Width	Length
Toy hauler (slides in)	13'6"–14'2"	14'–16'	18'–22'	+6'
Toy hauler (slides out)	13'6"–14'2"	14'–16'	24'–26'	+6'
Fifth wheel (slides in)	13'–14'6"	14'–16'	18'–22'	+6'
Fifth wheel (slides out)	13'–14'6"	14'–16'	24'–30'	+6'
Larger units / dual slides	13'6"–14'2"	16'	26'–30'	+8'

* Rig height includes AC units, vents, and any roof-mounted accessories. Always measure your actual clearance need before ordering.

Want to compare more ready-made options? Visit the metal building shop to browse RV carports, carports, garages, barns, and other steel building layouts.

Vertical roof: the right call for most RVs

A vertical roof has steel panels running up and down the slope of the roof, perpendicular to the ground. Water and snow run straight off the sides instead of collecting along the length of the building.

For a rig that sits outside year-round, this is the roof style you want. It handles heavy rain without ponding. Snow slides off instead of piling up until the load becomes a structural problem. And in states with high wind speeds, vertical panels lock together more tightly, which means better resistance to wind-driven rain getting in at the seams.

Our RV carports with vertical roofs are engineered to meet local wind and snow load requirements, so you're not just getting the right shape, you're getting a structure built to the codes in your area.

Still comparing roof styles? Use our metal building roof styles guide to compare regular, A-frame, horizontal, and vertical roofs before choosing your RV carport.

Before you order, measure it yourself

Manufacturer specs are helpful, but they’re not exact once your setup is involved. Do a quick walk-around and grab real numbers:

• Height – ground to the tallest point on the roof
• Width – once with slides in, once with them fully out
• Length – include hitch or full truck + trailer if connected
• Anything sticking out – steps, racks, awning arms

Then add your buffer:

• 18–24 inches above
• ~2 feet on each side
• 4–6 feet front and back

Round up from there.

Planning for wind, snow, or permits? Review our Snow and Wind Loads page to understand why certified buildings should match your local conditions.

Ready to size your carport?

You can configure your RV carport online using our 3D design tool, or browse our metal carports and RV carport options to see standard configurations and pricing. Every build is customizable for height, width, length, roof style, and color.

If you're in a state with specific wind or snow load requirements, our engineer-certified structures can be built to meet those local codes. Check our service area pages for state-specific certifications.

Have a size picked out? Call +1 (208) 572-1441 or use the 3D estimator to get your RV carport sized for your toy hauler, fifth wheel, roof accessories, and local code needs.

Get your RV carport sized and priced today

Design your building at EngineeredMetalBuildings.com or call +1 (208) 572-1441.

We'll help you get the right height, width, length, and roof style for your toy hauler or fifth wheel, sized to your rig's actual measurements and your local codes.

Need payment flexibility for a larger RV cover? Review our metal building financing options before you finalize your build.

You don’t have to spend weekends driving from one dealer to another or wait days for someone to call you back. These days, you can buy your metal building without ever leaving home.

The process is online now. Faster. More flexible. And you stay in control from start to finish.

Planning a workshop? Need a garage? Maybe a barn? Ordering online saves time, often saves money, and gives you far more options than most local suppliers can offer.

Why More People Are Buying Online

• Shop whenever it works for you.
• Find better deals, with discounts only offered online.
• See more choices in styles, sizes, and layouts than you’d find in person.

Once you start designing, everything’s laid out clearly. Change the size. Switch the roof style. Test out different colors. Every option is right in front of you. When it looks the way you want, you can place your order on your schedule, no pressure, no waiting.

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Seamless Online Shopping Experience

Our e-commerce platform is designed to guide you through the process step by step. First, you choose the type of building you need. From there, every option is user-friendly and clearly builds size, lean-tos, roof style, doors, windows, all with live pricing as you make changes. And when you’re done, the checkout is fast. No forms that ask for the same thing twice. No waiting around.You’ll also be able to follow your progress, from start to confirmation.

What stands out:

• The layout is clear, so you know exactly where to begin.
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Fully Customizable Metal Buildings

Ordering a metal building online isn’t just convenient; it lets you make it exactly how you want it. No sticking to a handful of pre-set models. No “close enough” designs. You can start small with a backyard shed or go big with a commercial building, and everything in between.

From the first click, you’re in control. Change the size. Pick your roof style. Add the number of doors and windows you need. Adjust the colors until they fit your property perfectly. As you make changes, you’ll see the updates instantly on your screen.

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Want specifics? You can choose dimensions like 30×40 or 40×60, or type in your own measurements. Go vertical or regular on the roof. Match the roof, wall, and trim colors to your taste. Add the right openings, frame reinforcements, or both. And with the live 3D view, you’ll see your vision take shape right in front of you.

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Certification & Insulation – Built for Where You Live

Metal buildings are built to last, but you can add more protection and comfort depending on how you plan to use the space.

You can order your building with a higher certification rating so it’s engineered to handle those tougher conditions. That rating isn’t just a number, it’s peace of mind that your structure is ready for what your climate throws at it.

Insulation is a smart upgrade if you will be working inside or storing sensitive items that are temperature-sensitive. It keeps summer heat out, brings warmth in during winter, and makes the building space more comfortable overall.

Upgrades include:

• Higher-rated certification — Up to 40 PSF or more, meeting strict building codes.
• Insulation options — Double Bubble for basic thermal control, 2-inch fiberglass for better coverage, or R17 Prodex for maximum efficiency.

Both options are easy to add during design. You’ll see exactly how they fit into your build before you finalize the order.

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Transparent Pricing & Flexible Payment Options

You’ll see the full cost of your building right away with no surprises later. This price covers the building itself, installation, and any extras you’ve chosen, like site preparation, color upgrades, or added structural features.

Paying is just as flexible. Put down a deposit or set up monthly financing. Choose what works best for your budget.

From time to time, seasonal discounted sales comes on site. On medium to larger structures, those discounts can really make a difference.

What you’ll notice:

• Clear breakdown – Every part of the order is itemized so you know exactly what you’re paying for.
• Different payment paths – Start with a deposit, or finance it over time.
• Discount opportunities – Watch for promotions, some going as high as 15% off.

The goal is simple: make buying your building straightforward from the very start.

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Add-Ons to Make Your Building Work Better for You

Every building starts with a solid base design. You can make upgrades that add strength, improve the design and looks, or extend its lifespan.

If you live in an area where winds hit hard, or you just want a durable setup, you can grab addons that include extra bows or mobile home anchors for added stability. Overhangs are another option - they provide additional coverage on the sides or ends and can alter the building's appearance.

You can also choose to add warranty coverage during checkout. That extra protection can help guard against rust-through or panel issues over time.

Some of the upgrades people often choose include:

• Extra structural support — Additional bows or anchors to reinforce the frame.
• Overhangs — Custom lengths on the sides or ends for more coverage and shade.
• Warranty coverage — Protection for rust and panel wear for longer peace of mind.

Not every project needs these, but in the right situations, they can be a smart addition.

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Wrapping Up Your Order

Once your building design is set, the last step is quick. You’ll see a single page showing every choice you’ve made - size, roof style, colors, doors, windows, and any extras.

Take a moment to check it over. If it all looks good, click “Buy Now” and fill in the required details to lock in your order. Right after, you’ll get a confirmation of your order.

From design to checkout, it’s just a few clicks - and you’re done.

Here’s what you’ll get before you finish:

• Order summary – All the specs you picked, listed in one place for easy review.
• Confirmation details – Your delivery timeline and follow-up instructions so you know what to expect.

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Visual Tools That Help You Decide

When you’re making a major purchase like this, seeing exactly what you’re getting matters. You want to be confident in your choices before committing — and the design tools make that possible.

You can view your building in 3D and spin it around to check every side. Change the colors. Swap features in or out. Zoom in to see the close details. The building images are sharp enough to show you the trim lines, roofing, and finishes clearly.

With these tools, you’re not guessing — you’re designing with your eyes open.

What’s available:

• 3D viewer – Rotate your design in real time while you build it.
• Detailed product images – See rooflines, trims, and doors up close before ordering.
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It’s the next best thing to standing in front of the finished building — without spending a dollar until you’re sure.

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Customer Support & FAQ – Here When You Need Us

Questions happen. Sometimes it’s right at the start, before you’ve even picked a size. Other times it’s mid-checkout, when you want to double-check a detail.

You won’t be left figuring it out alone. We have an FAQ with straight, practical answers - from how to buy a metal building, how to tweak a design, to payment steps, what the lead time is, to what the installers will do on site. No long-winded explanations. Just what you need to know.

If you’d rather talk it through, use the live chat. You’ll be connected with someone who actually knows the process and can walk you through it without making you wait for an email reply.

Here’s what’s in place:

• Live chat – Quick connection to a support rep who can give you clear, direct help
• FAQ section – Plain answers on design options, payment methods, installation timelines, and more.

The help’s there. The moment you need it. So you can keep moving and get your building sorted without the guesswork.

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Ready to Start?

Once you’ve had a look at the options, getting your design underway is straightforward. You can start right now, or step away and come back to it later — your progress will be waiting.

Everything is set up to keep the process simple. From customizing your building, to seeing the price update in real time, to checking out - it’s all built for flexibility.

Doesn’t matter if it’s a small backyard shed or a full-scale commercial build — the tools are ready when you are.

Click “Customize Your Building” and take the first step.