It is common practice to blend fibres to arrive at the most acceptable mix in terms of quality and cost for an end product. The best-known example is the 80%/20% blend of wool and polyamide, where the latter enhance durability and antistatic properties without noticeably affecting the ‘handle’ associated with wool. The relative lack of resilience in polypropylene is of no consequence in a fiat fibre-bonded carpet, but when blended in up to 50% by weight with wool in a tufted hard-twisted carpet, it adds bulk, stain resistance and significant cost reduction against an assessed acceptable reduction of the plus qualities of wool.

Comment

The important consideration is not so much a direct comparison between the fibres themselves as a comparison between the properties and construction of different carpets containing those fibres. The behaviour of a fibre in isolation is not necessarily a true guide to its behaviour within a carpet.

Principal Methods of Manufacture

All methods produce grades suitable for the contract market in a variety of wear surfaces and widths. Most can be combined with specially engineered backings and/or cut to sizes to suit specific types of installation.

Woven carpets

In weaving, the backing structure is produced simultaneously with the insertion of the pile yarn. The two widely used processes are:-

Wilton

Originally a loop-pile construction (Brussels), the same loom became known as a Wilton when cut pile was introduced. Wilton carpets produce high quality cloth in either plain colouring or patterned in a limited number of colours.

Variations in the traditional Wilton weaving method include ‘carved pile’ carpets and a type of loop-pile carpet too. Some Wilton carpets are manufactured by what is known as the ‘face-to-face’ method or ‘sandwich weaving’ in which two carpets are woven simultaneously, and then the pile strands in the ‘sandwich’ are slit apart to form two lengths of carpet.

Axminster

These were originally Spool Axminsters, with almost unlimited capacity for colours per design. The Gripper version was later introduced, using the Jacquard mechanism and direct insertion of tufts, thus reducing to a single stage operation. Gripper carpets also provide a firmer back, but the number of colours is again limited. Tuft density, for contract quality reaches 70 per sq.inch (7 pitch). Small production runs in bespoke designs and colourings are available.

In making Axminster carpet, the pile is inserted one row of tufts at a time, each row representing a section of the overall pattern. The tufts are ‘U’-shaped, and are anchored at the bottom into the primary backing which is woven at the same time. The backing may have a synthetic-starch or latex finish applied to it.

Because the weaving method permits a wide range of colours to be used, Axminster weaving has been traditionally used mostly for creating multicoloured patterned carpets; however, styles have changed, and many modern Axminster carpets do not have the large ornate designs with which this type of carpet was formerly associated.

Tufting

A tufting machine has a row of needles mounted in a needle-bar running the width of the machine. The needles are spaced apart according to the gauge of the machine —1/10" gauge has 10 needles to the inch. Each needle is fed with yarn from a separate cone. A primary backing fabric is fed beneath the needles. The bar then forces the needles through the backing, loopers catch the yarn and the needles are withdrawn. Thus a full row of tufts is stitched in one cycle. To bind the tufts firmly an adhesive or latex is applied to the back of the cloth and the secondary back laminated to it.

The process described is for loop pile, but a cut pile is produced by adding knives to the loopers. Many variations of machine are employed and together with attachments can produce high/low textures, cut and loop effect patterning by use of sliding needlebar techniques (Hydra shift and Graphics) and by overtufting. In this latter additional process, known as ICN, coloured yams are overstitched into an existing plain tufted carpet to form a pattern. A variety of backings many be applied including foam to avoid the need for a separate underlay (high density foam is needed for contract situations), secondary backings in woven jute or synthetics and impervious backings, such as plasticised pvc.

The pile materials used in manufacturing tufted carpet are basically the same as those used in woven carpets, but the form of construction is different. Tufted carpet is made by inserting the pile material with needles into a primary backing. The complex machine that is used somewhat resembles a multi-needle sewing machine. The primary backings are usually made from a synthetic pre-woven material or a non-woven material. The pile material is anchored into the primary backing by an adhesive (usually a latex compound). A secondary backing is then added to the carpet to complete its manufacture.

Fibre-bonded carpets

Fibre-bonded or needlepunch carpets are produced directly from individual coloured fibres, usually synthetic fibres. The fibres are laid as a thick web with a bank of many barbed needles. This entangles the fibres, converting them into a fabric of the desired thickness. This is then impregnated with latex resin which, after drying, bonds the fibres permanently together. Printing can be used to provide coloured designs. ‘Second generation’ products use an additional needling process to convert plain surfaces to ribs, velours and patterned textures. Backings such as high density foam and pvc can be applied for use in suitable locations.

For more than 30 years this process  has been successfully used and offers a very hard wearing traditional cut pile  finish. The more usual method is that  of a ‘U’ tuft product, where the fibres are pleated and the yarn is bonded to  layers of vinyl incorporating a glass fibre reinforcement for stability. The same process is applied to reverse side  of the cloth to form a face-to-face   construction before it is slit in the  middle to form the two finished cloths.   Latterly the ‘1’ tuft process had been  developed offering maximum   utilisation of the yarn in the wearing surface.

Fibre-bonded carpet is made by ‘needling’ a web of synthetic fibres to form a felted surface. This is finished with a backing of pvc or bituminous material to give dimensional stability. Other types of fibre bonded carpet may have a raised surface of fibres or a nap. This type of floorcovering is hard-wearing; it is used mostly in commercial locations, though DIY stores cater to the market for easy-to-lay floor tiles in this material.

Flocked carpet

Flocked carpets are made by projecting electrically charged fibres into an electrostatic field where they align themselves parallel to the direction of the electric lines of force and shoot vertically into a binder film. The fibres are then permanently bonded when this film is dried. Commonly the film is coated Onto a non-woven glass tissue and back-coated. The fibre lengths are from 2mm to 4mm and the pile density can be be varied to suit end purposes. Flocked carpets are generally patterned by the rotary screen printing method.

In this type of carpet, the pile adheres to the backing very firmly, making tuft loss practically impossible, and fraying at cut edges very unlikely. The carpet is not patterned, and the pile has a soft velvet appearance. Because of the method of manufacture, the backing is less flexible than in other types of pile carpets, giving excellent dimensional stability. There can be problems in using such a stiff carpet for stairs.

Carpet tiles

All manufacturing processes outlined can be utilised to make the wear surfaces for carpet tiles. Conversion from sheet form to tile involves the application of specially engineered backings, commonly bitumen of plasticised pvc and cutting to specific tile sizes. Depending on the manufacturers’ instructions, tiles may laid in a single pile direction to simulate broadloom, or the pile direction may be varied to give tonal effects. Ability to create designs by the use of differently coloured or patterned tiles.

What are the virtues of carpet tiles?

Carpet tiles have the virtue that stained or damaged tiles can be taken up and replaced. Also, a tiled carpet enables easy access to under floor services if necessary.

400mm (16 inches) square (usually found in DIY centres).

480mm (18 inches) square (usually an American size).

500mm (20 inches) square (The most common size and one that I would advise you request).

600mm or 605mm usually for paneled floors.

They come in various constructions including tufted carpet (loop, velour, velvet, twist) flocked carpet, needle felt,   etc. One type, which is very successful, is of a felt construction containing a proportion of animal fibre (sheep or goat’s wool) known in the trade as a hair tile. Some carpet tiles have an adhesive backing (usually for the DIY market) , but some are simply laid loose, or held in place with double-sided adhesive tape evenly spaced. The most common method of fitting carpet tiles is to use a release adhesive (Tackifier).

When carefully laid on a smooth floor, the edges of the tiles tend to amalgamate so that the joins are not noticeable. To give the impression of a continuous carpet, the pile of all the tiles must be laid in the same direction; however, by turning alternate tiles, a chequered appearance is created ( you must follow the manufacturers fitting instructions as if laid incorrectly your wear warrantee may be infringed). Carpet tiles of two colours can be laid to give a chequered appearance. Other designs can be devised, including borders of a different colour to the body of the carpet.

Shag pile / Saxony Style

A shag / saxony pile carpet is a tufted carpet having a pile greater than 15mm in height, but the pile is not dense. Such carpets have a decidedly luxurious look and feel about them, and are certainly very comfortable underfoot, but have gone out of fashion because they require special care, including occasional raking (with a special rake (plastic) that your carpet retailer or garden centre can supply) to bring up the flattened pile. Also be aware of possible danger to small babies from shag pile carpets, especially those of poor quality, for hairy bits might be pulled out by a baby who could choke on them.

Loop pile

The surface in which the loops are left uncut.

Sculptured Pile

A multi-level textured pile carpet. The pile is usually made up of saxony and loop pile. Sometimes called 'shadow style'.

Tonal

A  carpet having a pattern in two or more shades of the same hue. The design is usually very basic .

Semi-Worsted

A Shortened spinning system for staple fibres. Ideal for synthetic fibres, but semi-worsted fibres are few when compared to woolen spun yarns.

Twist pile

The spiral disposition of the components (different yarn types) to form a twisted yarn. This is the most popular style on the market. It is available in almost all yarn combinations of wool and man-made. It is available as berber, heather, tonal and plain styles. Many outlets sell on pile weight but beware this is not an indication as to the quality.

Twist pile is usually available in:-

Single ply yarn

Double ply yarn

Triple ply yarn

Pile weight = The total weight of pile yarn, measured in oz per square yard or grammes per square meter. There are many differing weights.

Hard Twist is a yarn with higher than normal twist, also known as a frieze twist which again is tightly twisted giving a rough knobbly appearance to the surface to the carpet.

Brussels Weave

A loop -pile carpet woven over unbladed wires. Weaving is carried out in a similar manner to Wilton and carpet is often referred to as Brussels weave.

Embossed Design

A carpet having an engraved appearance, usually achieved by hand tufting and by hand shearing longer denser pile.

Cord

A carpet where the pile hasn't been cut,  usually in lines giving a ribbed affect.

Plush

A carpet where the pile is cut at the same height longer than a velvet pile but shorter than a saxony pile.

Saxony

A Construction having a level cut pile, less dense and longer than a velvet and a plush in which each tuft is clearly defined.

Berber Styles

The term ‘Berber’ (or ‘Berber style’) originally referred to hand-woven rugs made in North Africa from undyed woollen yarn. Black, brown & white wool naturally from sheep of the same colour creating a mottled - speckled effect. Due to the random style of mottling a lined effect may be noticed, this is a feature of the style of carpet selected and not basis for complaint. A warning that this may ocure should be on the sample label as it can lead to a complaint and a lot of upset. 

Nowadays it is used to mis-describe carpets like Twist, loop, velvet and some sculptured carpets that use natural coloured wool or from dyed yarn having a ‘natural’ appearance. Some manufacturers have gone a stage further and used the terminology to carpets that use three or more colours to create the mottled / speckled effect. They are also known as 'Heather style, Cottage look, Country style, Cotswold Style and many others in an attempt to describe a natural homely appearance. They tend to help hide a multititude of small stains ( like the ones us coffee / wine drippers cause ) within the mottling of the the carpet.

It is very hard for the manufacturers if not impossible to guarantee the same blend from batch to batch. Different batches will not look good when laid side by side and will almost in all cases give rise to a complaint.