How to Choose a Hammock Tarp? 3 Factors You Should Care Most
Hammock tarp (also known as rainfly) is an accessory for hammock camping to protect camper from wind, rain, ice, and other harsh weather, or create a relatively private place for hammock hanger to rest. It’s a popular hammocking add-on for both noob and veteran campers, due to its versatility, flexibility, and lightweight, can be used in all seasons.
If you are starting to know about hammock tarps and are going to choose one for your next camping, you might meet various tarps with different types, materials and sizes, and have no idea of which one is proper for you. In this article, I’ll help you know basic knowledge about tarps and guide you to pick the one fitting for you.
How many types do hammock tarps have?
There are six main styles of hammock rain flys on the market: asymmetrical, square (or diamond), rectangular, hexagonal, catenary-cut, and winter tarps.
1. Asymmetrical tarp
Asym tarp is made of parallelogram fabric, it’s hung diagonally over the hammock to form an asymmetrical looking, it usually has one tie-out at side panel to pitch.
Compared with other same-size tarps, it’s the most lightweight one, has the least amount of coverage, provides the most surrounding views from the hammock, suitable for backpacking and gram weenie.
Some notices you should be aware of asym tarp:
- It’s mainly designed for vertical rain and breeze, if the downpour or wind comes from the sideway, it won’t work well for protecting. For this reason, if you want to take asym tarp for camping, you’d better see the weather forecast for your sites before setting off.
- To minimize the wind and rain, asym tarp has more limitations and requirements in site selection, sometimes it’s hard to find two trees to set it up well for protecting. So, it’s not recommended for newbie hammock hangers, hex or rectangular has more error room for them to fiddle around.
- It’s not suitable for use in the mountain areas, due to swirling wind and changeable weather conditions; not suitable for winter camping, you need more coverage of the tarp to keep warm.
- It’s ideal for daytime resting, some people use it to shade the glaring sunlight and keep the birds from crapping on them.
- You are limited to sleep in line with the direction of asym tarp, lay diagonally to cover your head and foot in each panel side.
2. Square/Diamond tarp
Square or diamond tarp is the same, made of square shape fabric and hung diagonally to form a diamond looking, it has one tie-out at each side.
Square tarp is lightweight and has more side coverage than asym tarp, it can have the same level of protection as the rectangle or hex tarp when pitched properly, while costs less material use, tie-outs, and price.
Like the asym tarp, the diamond tarp is suitable for dry seasons hanging only, it will not keep you warm when in cold weather. They both have less surface touching the ground, which is beneficial when lots of underbrush at the hanging site to interfere.
Because it is hung diagonally at 45 degree, the ridgeline is 1.4 times longer than the fabric length, like an 8′ long tarp has an11.2′ long ridgeline. So you should have a tradeoff at the spot selection, whether the site has that long distance trees for hanging the square tarp, or should I just replace the square tarp with a rectangle or hex one for more coverage if the site has such far apart trees.
3. Rectangular tarp
The rectangular tarp has the best coverage only second to winter tarp, it allows you to put the whole side of the tarp down to the ground, suitable for cool weather. It has 2 or 3 tie-outs on the side panel, versatile for different pitching ways to change the tarp into porch or pole mod, which creates more room for your hammocking site.
The downsides are also obvious, a) it has more weight than other style tarps, except the winter tarp. b) The rectangle tarp can’t be pitched tightly, the side panel will flap in the wind and create lots of noise.
4. Hexagonal tarp
Hex tarp is made of hexagon shape fabric, hung symmetrically over the hammock, it has two tie-outs on each side panel. Hex tarp has more weight and protection than asym and square tarps, but less than rectangular tarp. It can be pitched a little tighter than the rectangle one, but not as good as the catenary-cut tarp.
It’s suitable for people who like rectangular tarp’s full coverage, while want to save some weight, and become more and more popular on the market.
5. Catenary-cut tarp
Cat-cut tarp looks like a hexagonal tarp, but the edge is curved cut like a catenary, it often has two tie-outs at the side panel.
Catenary-cut tarp removes the fabric that could flap in the wind, so it’s lightweight and can be pitched tautly, as well as has little noise and wrinkles, compared with rectangular tarps. Cat-cut design increases strength and tautness, which minimizes the effect of stretching and sagging issues caused by tarps made from stretchy materials, like silnylon, which will stretch and sag after getting wet or long time use.
For the ridgeline, you might notice some cat-cut tarps have a curved ridgeline on pictures, in fact, it’s not a special cat-cut ridgeline, just because the ridgeline gets forces from the guylines, and pull it into a curved shape. If the forces from the guylines are released, the ridgeline will restore to a straight one.
The biggest challenge for a catenary-cut tarp is setup, it needs optimal site and angle to rig, otherwise, it will become extremely flappy and noisy, suitable for campers to set the tarp always in the same way.
6. Winter tarp
Winter tarp is also called all-season tarp or full coverage tarp, it’s the biggest and heaviest of all types, but has the fullest coverage and best protection, as well as privacy. It usually has extra flaps or doors at the end sides, which are cut out from the fabric, can be enclosed or folded to break the wind and keep the interior room a little warmer. Most winter tarp has four or more tie-outs at each side panel, two of them are for doors.
Some people might agonize over winter tarp or other standard tarps without doors, for the extra around 10 ounces weight of doors, it depends on camping site and season. One thing can confirm is that, if you go hammock camping in the winter or cold weather below 50°F, or a mountain area has swirling wind and unpredictable weather, winter tarp is definitely the best option. On the other side, the doors of the winter tarp can be snapped inside to make the tarp become a large rectangular or hexagon tarp when in the warm season, allowing the breeze to blow inside. So, if you don’t mind a little heavier weight of your gear or often go car camping, the winter tarp won’t let you down in any site and weather conditions.
Nowadays, you can add detachable doors to your rectangular or hexagonal tarp to transform it into a winter tarp, you can buy extra add-on doors from vendors, like Warbonnet’s trap door kit or 2QZQ’s grizz beak, these door kits can enclose both ends of the tarp to provide protection in inclement weather, offering have more choices to experiment and entertain with your tarps.
What size tarp do I need for my hammock?
Tarp size differs on the market, but the main principle is that the tarp should at least cover the whole body of the hammock.
For tarp length, the tarp should be able to cover the hammock and extend around 12 inches over each end for a full coverage. Often the same length of the hammock body will be fine, because hammock is in a sagging state when hanging up, and most hammock hangers use a structural ridgeline to keep the hammock taut in a constant sag. A typical structural ridgeline has a length of 83% of the hammock body, for example, an 11 feet long gathered-end hammock with ridgeline will have a 9 feet length, plus 1 foot extending area at each end, the total length of the tarp will be 11 feet, same as the hammock body length.
For tarp width, it has less effect than length, and most tarps have a width in 6-10 feet, so each panel will be 3-5 feet wide, it’s big enough to shed any levels of rain and wind. Minimalists prefer smaller panels for saving weight, while mountain campers like wider panels for better protection and can even touch the tarp side directly to the ground to form an A-frame shelter mod, also bridge style hammock needs a wider tarp than the gathered-end one.
Larger or smaller tarp, which one should I choose?
Larger tarps can have a size in 12’x10′, while smaller tarps can be in 8’x6′, for a specific tarp to go, depending on the elements of location, weather, experience, and budget, choose the best one that suits your demand. For a newbie hammock camper, I suggest starting from the bigger tarp, and can gradually decrease the size when you gain experience and skills.
Pros of larger tarp:
- A larger tarp has more protection in unpredictable weather, you can’t forecast the direction of blowing winds and storms, especially in high altitude and mountainous areas, keeping yourself dry is the first concern when you go for a long journey camping.
- A larger tarp allows you to have more room out of the rain, which you can hang out with a chair, set a fire to cook, and hang more gear on suspension. Besides, a larger tarp has more pitch options, you can transform it into porch mod, pole mod, or A-frame mod, more versatile and flexible. All these will add more comfort to your outdoor camping experience.
Cons of larger tarp:
- Heavy weight is the biggest downside, backpacker and gram weenie should consider twice before carrying it on.
- A large size tarp means a longer tarp ridgeline, which adds difficulty for selecting proper trees and hanging spots.
Pros of smaller tarp:
- Lightweight, minimal size means less weight and space taken when taking in the backpack.
- A smaller tarp will somehow promote your camping skills and tricks by forcing you to stay dry in any weather and conditions.
Cons of smaller tarp:
- Less coverage means limits of using it in harsh weather and cold seasons.
- Same camping condition, needs more efforts to pitch well, and more freedom restrictions for sleeping and moving around.
What’s the material the tarp made of?
Generally, any water and windproof fabric can be made into a hammock tarp, in the early camping age, some people use a blue cheap plastic polyethylene tarp from Walmart, which is too basic and bulky; some people use spinnaker cloth (short for spinn) for a tarp, which is light and crinkly, a high-end fabric at that time, but out of manufacturing nowadays.
Today, the most widely-used tarp materials are silnylon/silpoly, PU-coated nylon/polyester, and cuben fiber (also known as “Dyneema Composite Fabric”).
1. Silnylon and silpoly:
These are two different materials nylon and polyester coated with silicone at the surface to repel water, we’re familiar with nylon and polyester, which are widely used in camping hammocks, they have a similar weight level and a minimum 2000mm hydrostatic head waterproof rating. For differences, nylon is more durable and stronger, but will absorb water after getting wet and result in stretching. Polyester has lower strength, but will barely absorb water and stretch, and has better UV protection than nylon.
After siliconized, silnylon and silpoly inherit the characteristics from nylon and polyester, like twins, they have the similar weight, packing volume, and price. 20D (1.1 oz / yd²) will be strong enough for tarps using, higher denier means more bearing strength but costs more weight.
But silnylon will still stretch and sag after getting wet even with dew, and have a tendency to get misty inside, silpoly doesn’t have these issues and is more UV resistant. So, silpoly has a better comprehensive performance than silnylon, and is more recommended.
How to keep the silnylon tarp taut when getting wet?
As I mentioned above, the silnylon will stretch along the bias of the weave when getting wet, tautness reduces, then cause the side panels to become saggy and flappy in the wind, it’s annoying and inconvenient to walk outside to tighten the guylines during the night or in the rain.
There are two ways can mitigate this circumstance:
- Use shock cords to tie between tie-outs and guylines, shock cords function as self tensioners can automatically adjust the length when the tarp stretches.
- Use silnylon in a catenary-cut tarp, cut in curved edges, this construction increases tautness and minimizes the effect of stretches.
2. PU-coated nylon and PU-coated polyester:
These two materials are nylon and polyester coated with polyurethane at the surface, to enhance the capacity of water resistance.
Compared with silicone coating, PU coating has the same level of water repellency, while is cheaper and heavier, and may peel away over time, so it’s less durable than sil-coating.
For hammock tarps, PU-coated nylon and polyester are all good choices, can do the job in all weather conditions. Don’t worry too much about their qualities, some well-known manufacturers, like ENO, Hennessy, offer PU-coated tarps for sale too, and the prices are much lower than sil-coated or cuben fiber tarps. For a budget concern, PU-coated nylon and polyester are still recommended.
3. Dyneema composite fabric:
More known as cuben fiber (CF), it’s the most lightweight and expensive material for hammock tarps. Cuben fiber tarp is relatively new on the market, due to the limited availability and complicated taped and sewn manufacturing process, the price is far higher than silicone or PU coated materials.
Pros of cuben tarp:
- The most remarkable advantage is weight saving. For two similar-sized, 12′ long ridgeline asym tarps from DutchWare, tarp made from silpoly weighs more than 10 ounces, while the cuben tarp weighs less than 4 ounces. This is a significant upgrade in minimizing weight, especially for backpackers.
- Absorbs zero water. Nylon and polyester absorb more or less water after getting wet, while dyneema is zero, no need to worry about any stretchy issues, also it’s repairable with tape.
Cons of cuben tarp:
- It’s translucent, doesn’t provide shade. If you are concerned about privacy, the see-throughness of cuben might not satisfy you in the daytime. It can let light in, creates a greenhouse effect inside, it’s hot to sleep under it in the direct sunlight.
- It’s more noisy than nylon and polyester in blowing rain and wind, because of its crinkly surface, but it will soften up with use.
- It can not pack down small. The same size cuben tarp has approximately 2 times volume than silnylon tarp, although it’s super lightweight, but a lot bulkier.
- High cost. Similar sized cuben tarp has nearly twice price than silpoly one, you should consider clearly whether the expensive cost is worth the value it provides.
From the above analysis of three aspects of hammock tarps, based on your camping site and weather condition, you can choose from asym tarp’s minimal coverage to winter tarp’s full coverage, same length with your hammock is good to go. If you are a gram weenie, and cost is not an object, cuben fiber will not let you down. For most normal hammock hangers, silpoly and silnylon are nice choices. For low-budget campers, PU-coated nylon and polyester can meet your demand while performing not too much worse than others.