Polythene tarps are the most common available and available in a range of grades and sizes. Normally the lowest grade tarps is around 100gsm. Expect to pay around $125 for an 30ft x 50ft tarp. At this price, the tarps are made from a 100% waterproof lightweight woven polyethylene and laminated with eyelets at approximately one metre intervals set into a re-enforced hem. Most suitable for garden furniture covers, groundsheets but these tarps can tear easily in a gale and will chafe on sharp corners.
An effective solution?
Canvas tarps are more expensive, expect to pay around $460 for an 20ft x 30ft traditional canvas tarp. These sheets are the old fashioned way of covering equipment, narrow boats, vintage vehicles etc. Made up with double stitched seams and hems fitted with eyelets. Although fairly rugged, the main problem is that canvas tarps are heavy and so may require a number of people to fit over a large object. They may be difficult to fit tightly around more complex shapes. Finally they are difficult to clean and so can quickly look tired and scruffy.
Mono type covers are a reinforced polythene heavy grade waterproof tarps which is suitable for more rugged purposes, most commonly found to wrap scaffolding around buildings. Ready to use eyelets are spaced at one 4ft intervals in the reinforced hems and all four corner eyelets are reinforced by a corner patch. Although they are more rugged, than a standard polythene tarps they are typically only available in a narrow range of sizes. Expect to pay around $300 for a 40ft x 20ft roll.
Shrink wrap should not be confused with ‘pallet wrap’ or ‘cling film’ that is stretched around an object and gives minimal protection. Heavy duty shrink wrap is draped over an object before shrinking tight. It is the shrink process that gives shrink wrap the strength and durability vital for industrial storage and transport applications.
Fitting shrink wrap
Whilst a tarps is simply thrown over an object and tied down, fitting a shrink wrap cover can be a lengthier process. Unlike a tarps which is held down by ropes attached to eyelets located around the hem of the tarps, a shrink wrap cover uses an alternative method. Instead of metal eyelets, which can damage the product being protected, a ‘perimeter’ band of tough strapping or rope is run around the bottom of the object being covered. The shrink wrap is then placed over the object and flipped around this perimeter and and heat welded back on to itself. Once the shrink wrap is anchored in this way it can be ‘shrunk off’ using a hot air tool. The ‘shrinks to fit’ characteristic makes shrink wrap particularly good at protecting awkwardly shaped products.
Although shrink wrapping is a very simple process, there are a number of techniques required to get the best result and so it is normally recommended that some kind of staff training is undertaken. This training should not take more than a few hours. Alternatively, if staff are not available or the requirement for shrink wrapping products is occasional, you may be able to find a specialist shrink wrap company who offer an on-site shrink wrap installation service.
Tarps are generally only available in a limited range of standard sizes. Shrink film is available in rolls up to 40ft wide by 400ft long. However, because shrink film can easily heat fused together there are no limitations as to the size of object which can be protected. Done correctly, two sheets of shrink film heat welded together will be a strong and waterproof as the original wrap. In addition, unlike a tarps, a shrink wrap cover can be fitted with a zipped access door, and can be fitted with self adhesive vents accorded to requirements.
Shrink Wrap Durability
Unlike a tarps, because shrink wrap is heat shrunk around an object, it becomes tight and does not flap and ‘self destruct’. This is the secret of it’s durability. Shrink wrap has been tested on large objects in the harshest conditions – as deck cargo crossing the worlds oceans with very positive results.
Once the product has reached it’s destination, the shrink film must be removed and recycled – shrink wrap cannot be re-used. The ability to re-use a tarps is often cited as the main advantage to tarps when compared to shrink wrap. Although the cost of tarps is generally higher, because they can be re-used it is normally thought that the overall cost compared to shrink wrap is lower. Whilst this can be true, in many situations, companies may find it difficult to get tarps returned and there will certainly a cost of doing so which must be taken into account. Using tarps also requires additional expenditure on periodic maintenance.
Another benefit of using a shrink wrap cover is that, because it fit’s so tight, entry is impossible beneath the cover. To gain entry, the cover must be cut which makes it obvious if the product has been tampered with in any way.
In a competitive market, where the product is being delivered to a customers premises, the smooth, slick glossy white shrink wrap covering has another advantage over a dirty tarps – that of image. It is no surprise that boat builders, who previously had been delivering a vessel worth upwards of $500k + covered in road grime were the first to see this aspect of shrink wrap.
In conclusion, it is clear that both shrink wrap and tarps have a valuable role in protecting large pieces of plant, machinery and equipment during storage or delivery to customers. Tarps are readily available and require little skill to fit, whilst industrial grade shrink wrap is available from a limited number of specialist suppliers and may require some staff training to get the best results.
Tarps are best suited to smaller, lower cost items where the tarp cover can be returned once the product has been safely delivered or stored.
Using shrink wrap is most advantageous for particularly large or particularly valuable objects, which need to be transported long distances with 100% peace of mind that they will remain protected from damage.