What is a Rain Fly: Here’s Why You NEED One

by | May 14, 2023 | Tents

Camping is more than just a pastime. It’s a call to adventure, an escape from the ordinary, and a rendezvous with nature. But as any seasoned camper will tell you, the difference between a delightful getaway and a damp disappointment often comes down to one thing: preparation. So, let’s make sure you’re ready!

In this comprehensive guide, we discuss the question, “What is a rainfly?” and uncover its significance as your indispensable ally against the elements. Armed with this knowledge, you’ll be poised to face any weather, transforming your camping trips from mere outings into epic tales of resilience and enjoyment. So, why wait? Let’s dive in, and by the time we’re done, you’ll be a camping pro, adept at wielding the power of the rain fly.

What is a Rain Fly on a Tent?

A rainfly is the outer layer of fabric that covers the body of a tent, either partially or fully. It is usually made of polyester material and is designed to cover the mesh on the tent so it can provide protection against the elements, such as rain, wind, and UV radiation. The rain fly can be attached to the tent using zippers, clips, or Velcro and is typically made of waterproof, water-repellent, and breathable materials. The rain fly and the tent footprint form an essential protective barrier for your shelter.

Primary Function of a Rainfly

The primary function of a rainfly is to help the tent stay dry and shielded from rain, dew, and other precipitation. It is essential for most camping adventures, as even the best-weatherproofed tents rely on the rainfly for optimal protection.

Apart from rain coverage, a rain fly also offers:

  • Extra insulation (warmth)
  • Wind protection
  • Dew protection
  • UV protection
  • Protection from dirt, tree sap, bird droppings, and grit
  • Privacy

Do You Need A Rain Fly?

The need for a rain fly depends on the weather conditions during your camping trip. If you expect rain or heavy dew, a rain fly is essential to keep the tent dry and prevent water from getting inside. Even the best-weatherproofed tents depend on the rain fly for the system to work.

If it’s dry and warm, you may choose not to use a rainfly to allow for better ventilation and air circulation inside the tent. However, it is still recommended to keep a rainfly handy, as it can provide additional protection from dirt, debris, bird droppings, and UV rays. Plus, having it on hand means you can put it on if you encounter any pop up rain storms.

When to Use a Rainfly

  1. Rain: A rain fly is necessary during rainy conditions to prevent water from seeping into your tent and to provide extra protection against strong winds.
  2. Cold: In colder conditions, a rain fly can help retain warmth inside the tent by acting as an additional layer of insulation.
  3. UV Protection: A rain fly can protect your tent from harmful UV rays, which can degrade the fabric over time.
  4. Dew Protection: Even when it isn’t raining, a rain fly can keep your tent dry by preventing morning dew from accumulating on the tent surface.
  5. Privacy: For some tent models, a rainfly can offer an additional layer of privacy, especially if the tent body is mainly made of mesh material.

When Not to Use a Rain Fly

  1. Hot Conditions: In hot weather, it is advisable not to use a rainfly, as it can trap heat inside the tent and make it uncomfortably hot. Removing the rainfly in hot weather can improve airflow and ventilation, making the tent cooler and more comfortable. Some people say to put on the rainfly during hot weather since it provides shade but that depends on the shape of your tent and the access to windows with the rainfly on.
  2. Stargazing: Some campers may choose not to use a rainfly on clear nights, allowing them to enjoy stargazing through the mesh top of their tent.

Do I Need A Tarp If I Have A Rain Fly?

While a rain fly provides excellent protection for your tent, having a spare tarp can be beneficial in certain situations. Tarps are versatile and can be used for various purposes, such as creating additional shade or as a makeshift shelter in case of emergencies. If you have enough packing space and don’t mind the extra weight, bringing a tarp along with your rain fly is a good idea.

If you want to use a tarp in addition to your rainfly, we don’t recommend just laying it on top of your tent. This can create a moisture trap between the two layers and it holds condensation inside the tent because the fabric isn’t as breathable as just the rainfly.

If you want the extra protection, setup the tarp so that it hangs above your tent. You can do this using ropes and a static attachment point like nearby trees. This provides additional rain protection without sacrificing breathability.

Tarp vs. Rain Fly

While a tarp and a rainfly may seem similar, they serve different purposes and have distinct features.

  • Weight and Packing Size: Rain flies are generally made of lighter materials and pack smaller than tarps, which is crucial for backpacking trips.
  • Custom Fit: Rain flies are designed specifically for your tent, with loops and attachments that work with your tent poles, stakes, and guidelines.
  • Durability and Insulation: Tarps are generally more durable and offer better insulation than rain flies, but they can be heavier and bulkier.
  • Breathability: Rainfly fabric is meant to be breathable to that condensation can get out but rain can’t get in. Tarps aren’t breathable and will hold back moisture from both directions.

Both tarps and rain flies can be used for minimalist camping, where campers forgo a tent and use a groundsheet, sleeping bag, and an overhead covering instead. Specialized rain flies with specific cuts and angles can provide better shelter than a tarp when camping with a hammock.

Are There Reasons To Use A Rain Fly Even With No Rain?

There are several reasons to use a rainfly even when there is no rain in the forecast:

  • Protection from morning dew: It can help keep your tent dry by preventing moisture from settling on the tent fabric.
  • UV protection: It shields your tent from harmful UV rays, prolonging its lifespan.
  • Wind protection: Acting as a shield, it can help block wind, offering additional insulation and warmth.
  • Privacy: For those preferring solitude, it can provide privacy, especially for tents with large mesh windows or doors.

Should You Use A Rain Fly When It Is Hot?

The decision to use a rainfly during hot weather is a matter of personal preference and the specific conditions of your camping site. Some campers prefer to leave the rain fly off at night to enjoy stargazing and better airflow.

One argument is that the rainfly traps heat, making the tent hotter. Others argue that it provides shade, keeping the tent cooler if all flaps and windows are open. Ultimately, it depends on factors such as the tent’s design, the shade provided by the campsite, and your comfort level.

Can You Camp With Just A Rain Fly And No Tent?

Camping with just a rain fly and no tent is possible, although this minimalist approach may not be suitable for everyone. Camping with only a rainfly can save space and weight, making it an attractive option for those traveling by bicycle or motorcycle or attempting long-distance hikes.

Using only a rainfly provides some privacy and protection from the elements but may not be as warm or secure as a full tent. Insects and small critters may still be able to access your sleeping area, and there is a higher likelihood of rain or dew entering your space.

When camping with just a rainfly, consider using a groundsheet or footprint beneath your sleeping bag for additional insulation and to keep your camping gear dry. Alternatively, a bivy bag can provide added warmth and rain protection.

Replacement Tent Rain Fly

If your rainfly is beyond repair or has been lost, you can get a replacement from the tent manufacturer or purchase a universal rainfly from online retailers like Amazon. A universal rainfly may not fit as tightly as the original one but will provide adequate protection for your tent.

If your rainfly is salvageable, you may be able to re-apply the waterproofing and breathe new life into the fabric. This is done by scraping off any flaking materials then following the manufacturer instructions on your waterproofing spray of choice.

Partial-Coverage vs. Full-Coverage Rain Flies: Which One is Best?

The choice between a part-covering and a fully-covering rain fly depends on your tent design and personal preferences.

Partial-coverage rain flies offer better ventilation, reducing the chances of condensation and mold growth. The also save money because the manufacturer can use less materials that a full coverage one would require. In contrast, they don’t offer as much weather protection.

Full-cover rain flies cover the entire tent and provide complete protection from the elements (like heavy rain and high winds) but can trap heat and reduce airflow inside the tent. They are ideal for anyone who frequently experiences rain and wind on their camping adventure as it provides better protection and weather resistance.

Typically (but not always) smaller tents will have more robust rainflies than larger budget-friendly tents. You can see below the Copper Canyon LX 8 (top – best 8 person tents) has a small rainfly compared to the full coverage one on the North Face Stormbreak 2 (bottom – best tents under $200).

what is a rain fly

Ventilation and Condensation Issues with Rain Flies

While tent rain flies are essential for keeping your tent dry, they can sometimes create another issue: condensation. This is because the waterproof material of the rainfly can trap the warm air that you exhale inside the tent. When this warm air comes into contact with the cooler surface of the rain fly, it can condense into water droplets, which can make the interior of the tent damp.

There are a few ways to mitigate this issue:

  1. Adequate Ventilation: Make sure your tent and rainfly have adequate ventilation options, like mesh windows or vents that can be opened or closed. This will allow the warm air inside the tent to escape instead of condensing on the interior of the rain fly.
  2. Use of a footprint or a tent floor: This can help prevent ground moisture from rising into the tent and condensing on the rainfly.
  3. Only use the rainfly if you need it. On clear, warm nights, there’s no need to use the rainfly, so keeping it off will mitigate condensation.
  4. Site selection: Try to set up your tent in a spot with good natural airflow, like on a slight ridge, rather than in a sheltered or low-lying area where cold air can pool.
  5. Weather conditions: In dry conditions, consider leaving the doors or windows of your tent partially open to promote airflow. Of course, if it starts to rain, you’ll need to close everything up.
  6. Single-wall tents and condensation: If you’re using a single-wall tent (where the tent and rain fly are one piece), condensation can be a bigger issue. Look for single-wall tents with built-in vents, or consider using a two-wall tent (with a separate rain fly) for better ventilation.


Understanding what a rainfly is and its importance in your camping setup is crucial for a successful and comfortable outdoor experience. A rainfly is an essential piece of camping equipment because it keeps your tent dry, provides extra insulation, and protects your gear from the element. We hope this guide has answered all your questions about rain flies and their role in ensuring a safe and enjoyable camping adventure in the great outdoors.


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