What is the expected life span of an enclosure? There are a lot of variances, and this article is prepared to give you the information needed to determine the life of a given enclosure.
The least expensive of boats will typically have roll vinyl curtains. These are made from a clear pvc material that typically comes 51” wide on a roll and can be .015, .020 or .030 in thickness. It is soft and the life span is very short and unremarkable.
Better boats may have pressed polished sheets. These are made using the roll vinyl that is cut to approximately 101” long by the 51” width. Two pc are pressed together between highly polished heated metal plates. This process renders a sheet with a firmer hand and a polished surface less susceptible to distortion. Use of .015 roll goods produces .030 sheet, .020 produces .040 sheet (most common) and .030 produces .060. These sheets are quite susceptible to scratching therefore fresh water life is greater than that of harsh saltwater. Life on the saltwater provided proper rinsing after use is 3 to 5 years. These panels should not be stored rolled up as moister between layers will magnify and burn plasticizers out of the pvc. This is notable by the burn yellow/brown color.
Two Premium scratch resistant Pressed Polished Sheets are currently on the market that are made from the pressed polished sheet with the addition of coatings. Neither product is visibly different than conventional pressed polished. Strataglass first came on the market in 1994 boasting its scratch resistance. Longevity is quoted from the Strataglass site; “Strataglass will have a useful marine life of 2-5 years when properly cleaned and maintained using Strataglass Protective Cleaner and Strataglass Protective Polish by IMAR, as directed by the manufacturer.” It should be noted that sunscreen will ruin Strataglass. The second Premium coated product and more recent to the market is O’Sea. O’Sea is resistant to sunscreen and hydrocarbons which can be important on diesel boats. Its longevity is stated to be 4-7 years when properly cared for. When either product is scratched beyond its resistance that scratch is permanent.
Polycarbonate enclosures are rigid and have been around since about 1993. Polycarbonate is subject to degradation by UV prompting several different versions with various claims to preventing the yellowing that naturally occurs in this product. Polycarbonate is easily identified by looking through polarized sunglasses at an angle, a rainbow effect will be present like that of oil on water. When new, polycarbonate transmits approx. 86% of light making it near the clarity of glass which is 89%. It comes in various thicknesses that can be sewn ranging from .030 to .080.
– Uncoated Polycarbonate is soft, will scratch easily and turn yellow quickly. The usable life expectancy is short and its light transmittance goes down rapidly.
– Coated Polycarbonate such as Makrolon/Tuffak AR has more resistance to yellowing and to scratching. In a flat stable application this product can be expected to last 3-4 years however it is not meant for flexing applications and when used around curves the outer coating is stretched and the interior coating is compressed resulting in vertical crazing in relatively short order.
– Makrolon/Tuffak Marine 5 Polycarbonate has a five year warranty that covers crazing. Thicknesses of .080 should not be used on a radius tighter than 30” and .060 should be no tighter than 20” or the warranty is void. Its warranty will replace sheet material on panels when more than 25% of the panel is crazed and that crazing is visible from 3 feet.
The first rigid enclosure, “Clearview Hard Curtain” utilized Acrylic and was invented in 1989. Acrylic is inherently resistant to UV and will not turn yellow. Its light transmittance is 92% and does not change more than 3% over ten years. So, even after ten years it is as clear as glass and no rainbow colors with polarized glasses. Acrylics cannot be sewn so a bonding process is used for fabrication of enclosure panels. This makes it particularly important that it be fabricated by a reputable or certified shop. Acrylic can be used on curves up to 220 times its thickness meaning that .080 can be used on up to an 18” radius and .118 a 26” radius. Tighter radius will stress the acrylic and shorten its life. Acrylic can be line bent with heat. Acrylic has a 9,800 Lb tensile strength which is utilized when cruising with panels in the closed position. However, when bent beyond its limit acrylic can break. The most common causes of this is due to zippers not being fully open when pulling a panel up to an open position which exerts excess pressure at that given point. An expected life span of acrylics is ten years and beyond. The life span of the enclosure is largely dictated by the border fabric used. There are several different acrylics currently being used for enclosure fabrication;
– AquaGlass® Acrylic is used after 2009 by EZ2CY® and used by other marine enclosure fabricators. This acrylic blocks approximately 70% of UV. It is a modified acrylic and the extent of those modifiers makes buffing scratches out more difficult than some other acrylics.
– clear2sea uv™ patent pending acrylic blocks 98% of UV. It is exclusively available through members of the 4U2SEA™ Fraternity of fabricators. It is a modified acrylic to the extent that buffing scratches out remains relatively easy.
– cool2sea™ patent pending acrylic blocks 98% of UV and approx. 23% of infra-red heat making it almost ten degrees cooler than any other enclosure. From the outside it is easily identified by its green hue, however, from the inside looking out this hue is not evident. Additional properties imparted include reduction of glare and enhanced night vision. It is exclusively available through members of the 4U2SEA™ Fraternity of fabricators. It is a modified acrylic to the extent that buffing scratches out remains relatively easy.
Click to download: Compare acrylic polycarb
The clear is only one component of an enclosure. As one advances to the longer life products, other components need to advance as well, or it will be for naught. High end enclosures should be constructed with lifetime threads so they will not have to be re-stitched during that lifetime. Border fabrics need to be of sufficient quality to survive the years as well. Currently zippers are the weakest link but some companies take steps during fabrication to insure the longest life possible out of them. One thing to note; if one zipper goes bad, its time to replace all.
By Jeff Smith
Have Questions? Feel free to contact me.
Jeff Smith (Pioneer of the Rigid Enclosure)
Email: Jeff@cy4ez.com | +1-410-507-1122