Metal RV Garage: Sizes, Costs & Size Planner

An rv garage keeps a $50,000 to $300,000 vehicle out of the sun, hail and snow, and out of a storage lot you pay for every month. It also keeps it out of the driveway, where many HOA rules do not let it stay. A steel shell is the common way to build one, because the frame spans wide bays with no posts in the way of a motorhome.

This page is for owners pricing a first rv garage, whether it holds a motorhome, a fifth wheel or a travel trailer. It covers what size fits each type of RV, how tall the door must be, what a kit and a finished building cost, and what the power, water and drain work adds. The size planner at the top of this page handles the exact fit. Use it first, then come back here for the numbers behind it.

RV Garage Sizes by RV Class

Start with the rig, not the building. Every rv garage is sized from the coach inside it. RV dimensions swing a lot inside one class, so the table gives the published range for each type. These are typical figures from one RV publisher. Your own coach can sit outside them, so measure it with the awnings stowed and the roof air conditioner on top.

Source: an RV rental marketplace's dimensions guide. The RV Industry Association at rvia.org publishes the trade data, but not a size chart, so check your owner's manual for the exact figures.

From RV Size to Building Size

The RV is only part of the footprint. You need room to walk around it, open the doors and run the slide-outs. The same guide notes that slide-outs typically extend 2 to 3 feet per side when deployed. If you plan to open them inside, the clear width has to include that.

A workable rule is the RV's length plus about 4 feet at each end, and its width plus 3 to 4 feet on each side. Run that through the planner and round up to the next standard frame width for your rv garage.

Those are planning starting points, not engineering. A supplier sets the final frame width and bay spacing for your site and loads.

Door Height, Width and Eave Height

The door decides whether the coach gets into the rv garage. A residential garage door is built for cars at 7 or 8 feet. It will not clear any Class A or fifth wheel in the table above, where the tallest listed height is 13.5 feet.

Leave about a foot of margin above the tallest point of the rig, and more if the driveway rises into the opening. That puts a Class A or a fifth wheel behind a 14 to 16 foot tall door. A Class B, a Class C or most travel trailers fit a 12 to 14 foot door. Width of 12 feet suits most RVs. Go to 14 feet for a wide Class A with mirrors, or if you back in at an angle.

These figures are our planning guidance, built on the published heights above plus a margin. They are not a code requirement. The eave is the sidewall height, and it has to sit above the door header and the door tracks, so it runs a foot or two taller than the opening. Every foot of eave adds roughly 3% to the kit price.

Which Door Style

A sectional overhead door is the usual choice. Residential-style sectional doors are specified to a DASMA standard, and tall ones are available with insulation. A roll-up door saves headroom because it coils above the opening, which helps when eave height is tight. A bi-fold or hydraulic door suits very tall openings but costs more, so get that line itemized in each quote.

Many owners fit a drive-through layout, with a door at each end, so the RV never has to back in. Another option is a pair of doors on one sidewall. Either way, ask for door pricing as its own line.

Metal RV Garage Cost: Kit Prices and Installed Totals

The cost to build an rv garage has two layers. The kit is the steel package: frame, panels, trim, fasteners and engineered drawings. It is materials only. The finished building adds a slab, erection, site preparation and permits, and those can match or exceed the kit.

Kit pricing falls per square foot as the floor grows. Under 600 square feet it runs $13 to $25 per sq ft, from 600 to 1,500 sq ft it runs $9 to $32, from 1,500 to 3,000 it runs $7 to $24, and above 3,000 it runs $7 to $22. These are ranges across suppliers and specifications. Your quote lands somewhere inside one.

Installed means kit plus a 4-inch slab at $6 to $12 per sq ft, erection at $5 to $12 per sq ft, site preparation at $1,300 to $5,600, and permits at $500 to $3,100. Insulation, electrical and plumbing are not in these totals.

One Worked Example: 24x40

Here is a 24x40 shell, 960 square feet, built up line by line. Every total is the sum of its lines.

Slab and site figures come from national cost guides, and erection is what metal building suppliers publish. Metro and coastal crews charge 25 to 40% more than rural ones, and a hurricane rating ran about 20% higher for the same size.

What Pushes the Price Up

Red iron frames cost more than light truss frames. Taller eaves, larger doors, a heavy snow or wind package and painted panels all move the quote toward the top of the range. A tall door is the biggest single change in an rv garage quote, so price it as its own line, and read the RV storage building cost guide if you are building rental bays rather than a private garage.

Kits are sold by many suppliers, so an rv garage kits search returns plenty of options. Compare what is in the box before the price. The metal garage kits guide lists what a kit includes and leaves out.

An RV with Garage Space for a Car, a Shop or a Loft

Most owners want more than a parking space for the coach. A second bay for the tow vehicle, a work bench, or a place for the golf cart is the common brief, so an rv with garage space for a car is a standard request. Plan the rv garage as one building with a wall in it rather than two buildings.

A 30x50 gives a 12-foot-wide RV bay and room beside it. A 40x60 gives a full RV bay and a two-car bay with a shop wall between them. Put the tall door on the RV side only. The car bay can use a normal 8 to 10 foot door, which keeps the price down. For more on car-sized layouts, see the 3-car garage guide, and for a simpler building with the same footprint, the detached garage cost guide.

RV Garage with Living Quarters or a Loft

Living quarters is a different project. It adds a plumbed, insulated, heated apartment with its own permit path, and it is covered in the garage with living quarters guide. Check local code before you assume a metal building can be lived in.

A loft is simpler. An rv garage with loft space gives you storage over a work bench or a car bay. The loft has to be engineered as part of the frame. It cannot sit over the RV bay unless the eave is tall enough. We have no verified price for it, so ask each supplier to quote it as a separate line.

Power, Water and Dump Hookups

A well-equipped rv garage lets you plug in, charge the batteries and run the air conditioner for a test. It can also let you flush the tanks without leaving home. Each of those is a trade job, and each has to be planned before the slab is poured.

30-Amp and 50-Amp Power

RV power comes in two sizes. A 30-amp service supplies up to 3,600 watts through a three-prong plug. A 50-amp service supplies up to 12,000 watts through a four-prong plug with two 120-volt hot wires. Larger coaches with two air conditioners normally need the 50-amp outlet, according to an RV retailer's guide to RV amp service.

Check your coach's plug before you decide. Wiring a small building costs about $1,200 to $7,100 for the general package, and the RV outlet is added to that. An electrician can quote it once you know the amp rating and the distance to the panel.

Water and Sewer

A water line and a drain turn the building into a full-hookup bay. Both are plumbing, and plumbing pricing is local, so we have no honest national range. Get a plumber's quote.

The drain is where codes differ most. Some jurisdictions restrict floor drains in a garage, require a trap, or want the floor sloped toward the door. Rules also differ on whether the line may connect to a septic system. The model codes come from the International Code Council, and your local building department decides which edition applies. Ask before you pour the slab, because moving a drain afterward means cutting concrete.

Insulation, Ventilation and Floors

An uninsulated steel building sweats. Warm, humid air meets a cold panel, and the water drips on whatever is below. That is a design issue, not a flaw in the steel, and it is handled with insulation, a vapor retarder and ventilation. For an RV with tanks and water lines that cannot freeze, insulation also keeps the inside from dropping to outdoor temperature overnight.

Steel framing carries heat past cavity insulation, so energy codes generally call for continuous insulation over the framing as well. The R-value you need depends on your climate zone and the code edition your area follows. The DOE Building Energy Codes Program is the place to start.

Put a vapor retarder on the warm side of the insulation, which is the winter-warm side in a heating climate. Getting that backward traps moisture. Ask the installer which side applies where you live.

The floor is the other half. A 4-inch slab is what the price figures above assume, but a heavy Class A may call for more thickness or reinforcement. Ask the supplier and your slab crew what weight the pad is designed to carry. A graded floor or a drain handles washdown and melting snow.

Permits, HOA Rules and Site Work

Permits come first for any rv garage. Virtually all US jurisdictions require one above a small size, and the threshold is set locally. You will also need setbacks, a drawing sealed by an engineer licensed in your state, and sometimes a soil report. A permit costs $500 to $3,100 in most places, and site preparation another $1,300 to $5,600.

Wind, snow and seismic loads are specific to your address. There is no national number. The free ASCE Hazard Tool returns the values for a given address, and your supplier uses them for the sealed drawings. A building ordered for the wrong snow load is the most expensive mistake on this list.

HOA and Zoning

If you live in an HOA, read the covenants before you order an rv garage or anything else. Many restrict outbuilding size, exterior color, roof material or height, and a 14 to 16 foot door can run into a height cap. Get approval in writing. Some HOAs that ban RVs in the driveway are happy to see one go inside a building.

Zoning adds its own limits on accessory buildings, such as a maximum footprint and distance from the property line. A call to the planning office takes ten minutes and saves a redesign.

Kit or Crew: Who Builds It

Bolt-together kits are designed so an owner can assemble the smaller sizes with a crew of friends. Concrete work, the overhead door and the electrical hookup in an rv garage are normally left to licensed trades. A crew is the safer choice on a tall building, because the frame is heavy and the eave is high.

Erection is $5 to $12 per sq ft when hired out. Larger buildings sit near the low end, and small ones nearer $8 to $10. Crane work, tall eaves or a tight site can reach $15 to $18.

If you do hire, ask whether the quote covers the crane, the anchor bolts, the door install and cleanup. Two quotes at different prices are often two different scopes.

Conclusion

A good rv garage starts with three measurements: the length of the rig, its tallest point, and the width with the slide-outs open. From those come the door, the eave and the frame. The size planner at the top of this page does that arithmetic for you.

Budget the rv garage kit and the finished building separately, and plan the power and drain before the pour. Then get several quotes on the same specification. That is the fastest way to a building that fits and a price you can defend.

Related Resources

• Metal Garage Buildings: Sizes, Prices and Kits
• Metal Garage Kits: Prices by Size and What You Get
• 3-Car Garage: Sizes and Costs
• Detached Garage Cost: What You Will Pay
• RV Storage Building Cost: Complete Guide