3 Factors To Consider When Choosing Your RV: Length, Slides, & Height

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There are so many factors to consider when buying an RV. In this article, we will talk about the three main factors that you must think about: length, slide-outs, and height.Almost once a day someone asks me what RV they should buy. It’s my least favorite question to get because it’s an impossible question to answer! There are so many factors to consider when choosing your RV!

I have three neighbors, all married couples in their 50s. One has a 45-foot Class A diesel pusher. One has a 40-foot fifth wheel. The other has a 25-foot Class C.

Everyone is different! Choose your RV based on your personality and needs, not what other people choose.

There is a lot to consider when purchasing your RV. If you’re just starting to look into RV life, I’d recommend checking out my book, A Beginner’s Guide to Living in an RV, available on Amazon.

In this post, we’re talking about living space and I break down three of the biggest factors to consider when picking your rig.


Length is the single most inhibitive factor for RVers. There are plenty of roads–especially in national or state parks–that prohibit certain lengths of RVs. For example:

Pacific Coast Highway: 30-foot maximum

Signal Mountain Campground, Grand Teton National Park: 30-foot maximum

Chisos Basin, Big Bend National Park: 19-foot trailer maximum, 24 foot RV maximum

Generally, if you’re traveling in a rig that’s under 35-feet, you can go almost anywhere. People often worry that they will be unable to visit national parks in a bigger rig. You absolutely can! Grand Teton offers two campgrounds (Gros Ventre and Colter Bay) with sites for larger rigs and Big Bend has Rio Grande Village. (And every other park we’ve visited is the same way.)

We’ve never visited a national park where we were completely unable to enter in the RV (currently our rig is 33 ft). Some roads or campgrounds may be restricted, but all parks have areas where RVs can fit!

If you don’t plan on visiting a lot of national and state parks (that would be a mistake, by the way), then you really don’t have to worry about road restrictions based on length.

For most people, RV length is all about accessibility and mobility while traveling. But if you’re unsure how large of a rig you want to buy, it boils down to two important details:

    1. Weight 

Weight is especially important if you’re planning on purchasing a trailer or camper. You’ll need to look closely at the towing capacity on your truck and the GVWR (gross vehicle weight rating) of the rig.

Do not, do not, do not buy a rig that is heavier than what your vehicle can tow. You’d think that was common sense, but I’ve seen way too many pictures of people who have torn off the beds of their truck because they didn’t think about this!

If you’re looking at motorhomes, weight is less important—especially if you buy a diesel pusher.

But if you plan on towing a car behind your rig (we tow a Honda CR-V), you’ll want to look at the towing capacity of the motorhome. If you don’t want to tow at all and use a motorhome as your primary vehicle, you’ll probably want to look at buying a smaller rig.

[Check out our post on our many different towing experiences here.]

    2. Floor Plan

Weight is an important detail to note when deciding your ideal length for an RV, but the floor plan is typically the deciding factor for choosing length. Think about your must-haves in your rig. Maybe you know you 100% need an oven or two bathrooms or sleeping space for eight. Only certain lengths of RVs will meet all these requirements.

For us, we knew we wanted a floor plan that allowed two table tops for workspace, plus an oven and plenty of counter space in the kitchen. With only two people in our household, a motorhome between 30-35 feet was ideal for us. We upgraded from our 29-foot Class C to our 33-foot Class A and it is a WORLD of a difference. Four feet is a huge amount of space when it comes to RVs. 

To get an idea of what length of rig you’ll need, check out floor plans on manufacturer’s websites. You can see our Winnebago floorplan and even walk through an online simulation of our RV on Winnebago’s website. Our floor plan is the Winnebago Brave 31C.

Photo Credit: Joe Hendricks

Slide Outs

Slide outs (sometimes called pop outs or just slides) are portions of your RV that slide out when you’re parked to increase living space.

If you’re thinking “Alyssa, that’s the stupidest definition I’ve ever heard,” you’re probably right. BUT I’ve had to explain slides to a lot of confused people who actually thought my RV was 12 feet wide when I drove it down the highway. Oy vey.

Long story short: Slides are the best way to gain more living space. This is great if you want a shorter rig with ample space.

Slides are most commonly offered in class A’s, C’s, super C’s, fifth wheels, and travel trailers. Slides can be electric or hydraulic, depending on the manufacturer.

Do you want a rig with slides? YES.

They are a game-changer. Our first RV had zero slides. It made hosting guests or walking past each other, ever, pretty much impossible.

We now have two slides: One that’s about three feet deep and contains our dinette, and one that spans the entire length of the house and is about 18 inches deep.

These two opposing slides are fantastic for opening up the room and giving us a lot of floor space. I’ve seen very few other rigs with enough floor space to set up a stand-up desk and a yoga mat at the same time. If you prefer a more open concept RV, finding a rig with opposing slides is key.

You can expect to have issues with your slides at some point during your ownership.

They are known to be finicky, but the space is worth it. We’ve had issues with our slides on four occasions.

After purchasing our rig, we heard a few negative comments and reviews of full-length slides. We have had our large slide worked on three times in the past 18 months. In each instance, the slide was not coming in correctly. The front would come in faster than the back, or vice versa. Once the difference was so bad, our slide was out 6 inches in the back and not at all in the front. It was a nightmare!

The mechanic said this is called being “out of time.” (Dramatic, right?)

He re-timed the motors in the front and back of the slide so that they would start operating at the same speeds again. He said this happens often, especially with larger slides carrying a lot of weight.

Re-Timing Your Slides

A friendly mechanic in Denver taught us a trick to re-time our slides ourselves, should we ever get into trouble again. I’m not mechanically savvy at all, but let me drop some premium layman’s terms mechanical advice on ya.

Our dinette slide was giving us trouble and when took it out one day, there was almost a 12-inch difference between the front and back of the slide. It was dangerously close to getting stuck and Heath was outside manually pushing one side of the slide in while I religiously held down the button inside.

Typically when bringing in your slides, you hold down the button and do not stop for any reason. I remember the dealer drilling this fact into us when we bought ours. Do not stop while bringing in or taking out the slides!

However, when they start getting out of time, you can re-time them yourself by taking the slide out a few inches at a time, or until you notice the sides of the slide are going out at different speeds. Then stop and bring the slide back in until you line them back up again. Repeat until you have the slide out all the way. 

Heads up: It would sometimes take a full five minutes just to get out slide all the way out! 

After learning this trick, we would take the slide out three or four inches, using the lines of the faux tile linoleum to measure if each side of the slides were moving out at the same pace. It took about 20 sessions of bringing the slide all the way out and all the way back in, inching it back and forth the whole time, but our slide did re-time itself. 

Since getting repairs at RV service shops is often expensive or impossible, it felt amazing to be able to fix this issue ourselves.

That was almost a year ago now and we have had zero issues with our slide since!

Side note before we move on: Unless you’re buying a fifth wheel which is properly outfitted for excess weight, do NOT buy a rig with a refrigerator in the slide. I’ve heard horror stories. The less weight on a slide the better!


You have the least amount of control over the height of your RV. (I noted average heights for each type of rig in this post for reference.)

Here’s the deal with height: It is not a huge deal. Low clearances are rare, especially in the west and in the south. It likely will never affect visiting a specific destination, though it may alter your route.

Between All Stays, Co-Pilot, and our Rand McNally GPS, we never worry about running into low clearances. I recommend using at least one of these to check your route for clearances. Our Rand McNally GPS is built into our RV and our specs are programmed in, so we can trust it to never take us down roads we can’t handle.

In three years of full-timing, we’ve only found ourselves in one terrible must-u-turn-now situation with low clearances. We were driving the I-95 from Connecticut to NYC and Heath took a wrong exit, one with about fifty WARNING SIGNS: 8 FOOT CLEARANCE AHEAD signs. (He told me he saw none of them.)

A nice guy in a pick up flagged us down and said that if we wanted to keep our roof, we should follow him back to the interstate. We made it back on track in no time and I’m now a queen at backseat driving to make sure we never find ourselves in another heart-stopping situation like this!

Ultimately, there are a lot of factors to decide on when picking your first RV. Buying an RV is a mix of extreme excitement and a lot of stress in making the right decision. But it is totally 100% worth it! 

What is your biggest consideration when buying your RV?