If you are looking at inflatable tents for sale or flirting with overlanding or just want a new camping tent for the family, you must have come across something like ‘150D 320gsm Oxford Poly Cotton HH 6000mm’. Did you ever wonder what is the difference between tent fabric types? What is hydrostatic head, if you ever heard of it? Why is there a PU coating, what is a PU coating anyways?
Denier, thread count, gram per square inch, hydrostatic head…hmmm…
Lately it has become something we have seen before with personal computers, RAM memories, mobile phones, cameras or TVs: a lot of technical staff, NUMBERS most of all, thrown at you and OBVIOUSLY the bigger the better, right?
Well, not so much, when it comes to selecting tent fabric. Each tent fabric type has different qualities, good and bad points. Picking the right mostly depends on your NEEDS, the way you would use your tent, its purpose.
You probably have heard of many different types of tent fabric from polyester to poly-cotton, not to mention the different brand names like OutTex or Protex or Sentinel, just to mention a few. Of course, they all claim they are better than the others, but the fact that you don’t even know what’s behind the catchy brand names, does not help.
Perhaps you also noticed that there are more expensive and there are less expensive fabrics, but the fact that one is more expensive does not make it BETTER, if it is not FIT FOR THE PURPOSE you need it for.
Tent Fabrics Types – What is the difference?
So each tent fabric has good and bad points. For example, you may need a lightweight tent that is easy to carry, or you need one that you set up in the June and you won’t touch it till September, even in the poorest weather? Or you need something that dries quickly so you can leave the camp as early in the morning as possible?
The vast majority of tents are made of nylon or polyester. Here on 10ts-tents you mostly find polyester and poly-cotton tents, as nylon is more often used for lightweight backpacking tents, and not so much for large(r) and heavy(ier) family tents or roof top tents.
Polyester tent fabric
Polyester is a popular choice, because it is cheap, and it performs well in various weather conditions. Polyester is the most common fabric used in tents. Although it is not waterproof (unless coated), it doesn’t change shape when wet (unlike nylon) and does not perform too bad in sunlight. It is also more durable than nylon, and despite it is heavier, it is not too heavy and packs down fairly small. Polyester is also relatively quick to dry out and has natural resistance to mildew and rips.
On the flipside of the coin, especially if compared to the, THE, traditional tent fabric the cotton, polyester is not a good insulator. This means that polyester tents can get very hot when it is warm, and chilly when it gets cold. Also, especially when a coating has been applied, it is not breathable, which can lead to condensation building up inside.
Also bear in mind that they can lose colour over time through exposure to sunlight, and the fabric weakens to as the UV rays break down the molecules.
Pros: less maintenance, strength, stretch and tear resistance, not too heavy, affordable, packs down small, good mildew resistance, waterproof
Cons: Not great UV resistance, bad insulator, low breathability causing condensation, limited lifespan
Cotton / Canvas tent fabric
Cotton or canvas is the original, the one, the tent fabric your grandad probably used. A long time ago canvas was made from hemp, but nowadays tent canvas is made from cotton. Manufacturers tend to use both which can be confusing, but the two – cotton and canvas – are the same thing.
Cotton is thick, durable and breathable, and is naturally waterproof, does not need any coating. As water starts soaking the fabric, the fibres expand and swell, sealing off the gaps between the threads. It may leak the first time in rain as the swelling process takes time, so it is a good advice to weather/season the cotton tent before using it for the 1st time.
Cotton also has very good thermal properties, it is an extremely good insulator. The tent will remain cool in the summer, and stays warm if the weather turns cooler.
As it is naturally breathable and absorbs water, you won’t have any issues with condensation.
It is thick and heavy, which not only makes it a good thermal insulator, but it is a very good acoustic insulator as well: it is quieter, you are not going hear the lightest breeze flapping the thin fabric like on a polyester tent.
On the negative side, cotton is heavy and bulky. It is not easy to carry due to its weight, and you must doublecheck if it fits into the boot of your car. Pitching needs more effort too.
It also requires more maintenance. You need to dry the material out before putting the tent away, otherwise you will get mildew in the tent. And drying it out can take much longer than any polyester tent, as cotton absorbs water.
Cotton, as a natural fabric, rips much easier, which can turn into a huge tear very easily.
Lastly, cotton tents are not cheap.
Pros: breathable, naturally waterproof, less condensation, good insulation, long lifespan, high UV resistance
Cons: expensive, heavy, bulky, prone to mildew, can’t be used out of the box, requires maintenance, needs to dry out before packing away
Polycotton tent fabric
Poly-cotton is a blend of cotton and polyester. While keeping all the good qualities of cotton, it has some of the benefits of polyester tents. The main fabric is cotton, with polyester in the weaves, so it inherited some of the mildew-resistance, it is stronger and less likely to rip than pure cotton. Poly-cotton can be left uncoated but usually there is a coating applied to repel water.
Its durability, breathability and weather resistance make it great for family camping tents, swags and roof top tents.
Pros: better strength and mildew resistance than cotton, better resistance to UV and heat than polyester, breathable, less moisture and condensation, longer lifespan and better weight than cotton canvas
Cons: cost, still heavy and bulky, less mildew resistance than polyester
Oxford is a different type of weave which provides better strength and durability. Though it feels like cotton, waterproof, strong and durable; it is noticeably lighter.
Brand specific tent fabrics
Some tent companies brand their mix of tent fabrics, treatments, and coatings. This does not help in understanding the properties of the tent fabric, and ultimately it feels like I am being sold something that I don’t know anything about.
The table below doesn’t list every brand specific tent fabric, but I have tried to cover all that have been mentioned on the site before:
Kampa WeatherSheild: Polyester (WeatherSheild is basically the PU coating that Kampa applies to their polyester tent fabrics. It can vary in thickness and hydrostatic head ratings)
Outwell Outtex 100% Ripstop Cotton: polycotton
Outwell Airtex: Polycotton treated to help water droplets run off the tent.
Outwell Outtex 6000 Polyester: polyester with 6000mm HH PU coating
Vango Protex 70 Polyester: 70D polyester
Vango Protex 150 Polyester: 150D polyester
Vango Protex Cotton: polycotton
So which is the best tent fabric?
As I said at the beginning, it depends a lot on the purpose. When I write a review of an inflatable tent or a roof top tent, and I ask the question ‘who is it for?’; I always look at the fabric material first. Poly-cotton tents provide you with a much relaxed, home-to-home feeling thanks to their better thermal properties, making them ideal as a family tent. But due to their weight, I would not necessarily recommend them for a quick weekend-break; a polyester tent would fit that purpose a bit better. Each fabric has good properties and bad ones, and I cannot emphasise enough how important it is for you to know, how you will use the tent.
So for families, if you can afford, transport, and pitch it; go for canvas / cotton, or poly-cotton. The latter one, ie the pitching part, can be beaten easily if you go for an inflatable poly-cotton tent. If you camp in cooler weather ie outside the summer holidays, I would strongly recommend cotton or poly-cotton tents.
Otherwise, a polyester or nylon tent would certainly do a good job. If it gets too hot, just open the vents and make sure that you have as many mesh doors as possible, so you can let the fresh air in and keep the bugs out during the night.
Tent Fabric Specifications – What do they mean?
Denier (D) is the unit measuring the weight and thickness of the individual threads used in the fabric. The higher the Denier; the thicker, stronger and heavier the fabric. You must also count in the different types of fabrics as they have different strengths. A stronger fabric such as nylon normally needs less Denier to produce a strong and durable tent AND keep the weight as low as possible. So you will find lower Denier in ultralight tents and tarps.
Camping tents typically use higher Denier polyester fabric, most common values are 68D, 70D, 75D.
Camping tents with 150D or more are ideal for longer exposure to the sun and inclement weather. Apart from a few examples of 150D camping tents, this type of fabric is more typical in event shelters where it needs to endure more stress.
Rooftop tents are different beasts, and it is not uncommon to see 320-400D fabrics on them.
The thread count (T) represents the number of threads used per square inch of fabric. 190T for example means that 190 threads were used horizontally and vertically per every square inch. This also means that the thicker the thread is (higher Denier), the lower the thread count will be.
A higher thread count means a greater density in the fabric, so you will most likely find higher thread counts with lower Denier fabrics. But don’t fall for the numbers.
High thread counts can certainly make for better sheets of fabric, but it’s the thread itself, that matters most. In fact, a fabric of a better-quality fibre with a lower thread count will feel ‘softer’ and better-made than a fabric of a lower-quality fibre with a higher thread count.
So, a higher thread count doesn’t mean a stronger fabric, it depends on the quality and thickness of the fibre used. Actually, if nothing else is known about the flysheet or the groundsheet than the thread count (and it is intended to sound GOOD), I would become suspicious…
In simple terms it means the weight of the fabric, GSM refers to grams per square meter. But fabric weight is usually a definition of the thickness of the garment itself, but it is not always as simple as higher gsm means a heavier, thicker fabric.
You must also bear in mind that the weight does not tell you what type of fibre thread is used and how dense the thread count is. Fabrics with different fibres or weaves but with the same weight may not have the exact same thickness.
Also important to bear in mind that the weight of a material does not always determine its quality. Different fabric weaves will be different weights which is essential for its end use. While most tents range from around 280gsm to 380gsm, you will find the ‘high-end’ modern polycotton tents on the lower end of this range.
So, most of the time, the higher the GSM the stronger and heavier the canvas will be; but don’t compare apples to oranges…
Ripstop fabric is a thin, lightweight and waterproof material, made of a combination of different fabrics. During weaving, a stronger thread – usually nylon or polyester – is added at regular intervals, which forms a distinctive rectangular pattern. This reinforcement makes any rips and tears less likely to spread, which makes it ideal for using it in outdoors equipment, including tents and others such as waterproof jackets, bags etc.
While it is a high-quality, breathable material, the name RipStop is a bit misleading though…You see it everywhere, more often on expensive outdoors equipment and it is certainly a special feature on some mid- to high-range tents. But what does it mean exactly? Well, it certainly does not mean that the fabric won’t ever rip.
So, bear in mind when buying tents, that ripstop will limit the damage, but the tent won’t become miraculously ‘rip-proof’.
Still not clear?
What makes it even more confusing, is that tent manufacturers tend NOT TO disclose all the specs of the tent fabric they use. This virtually makes it impossible to compare two different fabrics. For example: tent A has a 150D polyester flysheet, tent B has a 320gsm polyester flysheet, while tent C has a 75D 220T flysheet. Those metrics don’t convert to each other, the 75D fabric could easily have a greater density of the thinner thread, thus making it even heavier than the 150D fabric. While the 320gsm does not tell anything about the quality, the density or the thickness of the threads…
What are the different tent fabric coatings?
Depending on the tent fabric, different chemical coatings can be applied to increase their performance, mostly their resistance to water and UV light.
Polyurethane / PU coating
The PU coating is used to make the tent fabric waterproof. It can be applied to polyester and nylon fabrics, creating a waterproof layer. It is affordable and has good breathability. It does not permeate the fabric, but it is more like a layer that sticks onto the surface, hence it allows the application of tape on the seams. Depending on the type of chemical used and the number of layers applied, it determines the Hydrostatic Head millimetre rating (see further below) of the tent.
On the downside it requires care to be kept clean and dry for storage. Another drawback that UV exposure breaks down the chemical bonds over time, thus reducing the weather-resilience of the tent through its life-span.
What you need to consider, that it DOES limit the breathability of the polyester or nylon fabric, so the thicker the PU coating the less breathable the fabric remains. It also means increased weight, increased costs, and the chemicals in the coating can also weaken the fabric.
Also, the quality of the coating can vary from manufacturer to manufacturer; which can ultimately determine how long you will be able to enjoy your camping without rainwater leaking through the flysheet…
Silicon coating (a.k.a silnylon)
Nylon – just like polyester – is not waterproof. Instead of a PU coating, you may find that a silicone coating is applied to a nylon fabric, which is called sil-nylon.
The silicon coating goes in between the nylon fabric threads, so on the plus side it reinforces the nylon fabric, making it more durable, as well as making it waterproof. Silicone repels water, so you can easily sweep the droplets off the silnylon surface. It dries much quicker as well.
On the flipside, silicone coatings are not cheap, and since they fill in the gaps between the threads of the fabric, air cannot get through either. The lack of breathing in the fabric means that condensation can build up quickly and it turns the surface of fabric very slippery.
Silnylon tent seams cannot be taped, as they won’t stick to the slick surface. The seams need to be sealed by hand, using a liquid seam sealant. To get around this, manufacturers may apply a silicone coating on the outside and a PU coating on the inner side, this is called the SIL/PU coating.
There are various other coatings that can be applied to tent fabrics. Most notables are the ones that give fire retardant properties, and the ones that increase UV resistance. UV resistance is also important to protect the PU coating from breaking down over time, so in effect the UV coating can contribute to the overall water-resistance of the tent.
Hydrostatic Head (HH)
Hydrostatic Head (HH) measurement shows how waterproof a fabric is. The measurement gives a reading in millimetres: this is the maximum height of the column of water standing on the fabric before the water would penetrate the fabric.
According to Ultralight Outdoor Gear, the test used to be carried out using a physical column of water, but as fabrics have developed, the ratings were getting too high for this method. Nowadays the test is done using a machine that replicates the downward pressure that a water column of such height would create. The machine increases the pressure of water that is pushed against the fabric until water is visible on the other side. The required level of pressure used to force water through the fabric is then converted into a measurement of how high the water column would have been. This provides the result of the Hydrostatic Head test in millimetres.
Most tents discussed here on 10ts-tents have at least 1500mm HH or (waaay) above. Generally, a 1000mm HH means that the tent is ‘shower-proof’. You can find this rating on cheap pop-up tents, beach tents etc. Heavy rain and wind would create greater pressure on the fabric, so it needs at least 1500-2000mm HH in order to be considered ‘water-proof’. Anything beyond 2000mm HH means that the tent will keep out water even it is being pushed through by something physical, ie vegetation rubbing against it, or a person or backpacks / gear leaning on it.
A groundsheet needs to have a higher HH figure around 3000mm or higher ideally, as the pressure on material can be quite intensive when you sit, sleep, or walk on it.
Canvas fabrics don’t have a HH rating as they have a different way to keep the water out (see above). However, there are some manufacturers who apply a light waterproofing treatment on their tent. This allows for a quicker drying time, and the cotton remains breathable too.
There is one thing that you must bear in mind – again – that the HH rating rates the fabric, not the water-proof qualities of the whole tent. There are many other ways rainwater can get inside the tent (zippers, seams, vents, lack of canopies etc.) so the overall weather-resistance of the tent depends on a lot of other factors.
That’s why you just simply cannot to say that a 6000mm HH tent is more waterproof than a 2000mm HH one. It is about the fabric. Not the tent.
There is one company as an exception: Quechua. They don’t (always) tell the HH rating of their tents (but when they do, it is 2000mm HH). On the other hand, they put their tents through rigorous testing to simulate horrible weather conditions (heavy storms, wind tunnel) and they measure the overall weather-resistance of their tents. It is impressive and very convincing, and I like this approach very much.
Not sure I have made it clearer for you, or you just have more questions. But I do hope that from now on you will be able to narrow down the vast choice of tents to the ones that you actually NEED.
If you still have questions, don’t hesitate to drop me a line (contact details at the bottom of the page) or leave a comment!