By P.J Arthur, Natural Fiber Installation Certification
In the previous issue of ProInstaller magazine (July/August 2017, p. 14), I addressed the importance of knowing how the construction of woven wool carpet is as critical as the installation itself, and offered tips on how to acclimate, manipulate and install the product. Now, I’d like to address the same points of successful installation methods for Axminster and Wilton carpets.
What is Axminster?
Axminster carpet is produced on a Jacquard loom. The loom operation simulates hand weaving because each tuft is individually inserted into the pile. It is possible for every end to be of a different color with unlimited scope of design. Generally, Axminster carpets can be woven with up to eight frames with the possibility of planting a few others. Complex and abstract patterns executed through use of color are possible.
Axminster carpet can be more readily identified than any other carpeting. The back of the carpet can be recognized by a ribbed like appearance running in its width. The stiffness of the carpet allows it to be rolled lengthwise not widthwise. This is due to the double weft shot and the use of heavy latex sizing on the backing (which also obscures the double shot).
Axminster has always have a cut pile surface and usually an even-height pile. Performance capability depends on pile weight and density.
Axminster carpet has no stretch in the width, only in the length. For axminster use architectural tack strip with three rows of pins, or two conventional strips with two rows of pins for carpet with heavily latexed backs, most woven and Berber-style carpet, and for rooms exceeding 30 feet. A firm pad should be used, preferably 32 oz. felt, wool, rubber, or frothed polyurethane foam.
Note: A soft pad will create looseness and not support the carpet. Note: Use duct tape on stair nosing to keep the pad from wearing in this high traffic area. Seam sealing is mandatory!
Direct Glue Installation
To minimize wrinkling and buckling, and to facilitate installation, the carpet should be unrolled and allowed to relax in the installation area for a minimum of 24-48 hours at a temperature between 65-95℉ (18-35C). To facilitate relaxation, pre-cutting carpet is recommended.
During installation, maintain fresh air ventilation at full capacity using exhaust fans. After installation, continue fresh air ventilation for 48-72 hours at normal room temperature by using the HVAC system at full capacity. Open doors and windows, if possible. These procedures help exhaust, dissipate and eliminate lingering orders from the installation.
Layout the carpet according to the seaming diagram. Carpet must be cut 3-4″ longer than the area measurement. Where applicable, allow for pattern repeat. Align all carpet breadths to their proper position and trim seams.
An appropriate seam sealer must be applied to the edges trimmed for seaming and cover the thickness of the backing without contaminating face yarns. Apply the seam sealer to the cut edge of the carpet and then place into the floor adhesive. Place the two roll edges together to form the seam while the adhesive is transferable, to seal both edges.
After sufficient adhesive application and open time, the carpet must be pressed into the adhesive and rolled with a 75-lb. roller to achieve full and complete coverage of the substrate and carpet backing, including penetration into the backing’s deepest recesses.
Double Glue Installation
Relaxing/Condition Carpet – Temperature conditions should be the same as a direct glue installation. The cushion must be installed in the longest continuous lengths possible with consideration to traffic patterns and carpet seam placement. Cushion seams must be at a right angle (90-degrees) to carpet seams or offset at least 6″. Cushion seams must be butted without compression, leaving no gaps.
The recommended pad to be used for double stick installation is a 21-lb. rubber slab pad. Felt or wool pads are not recommended for this type of installation.
Trowel size for double glue installation, is as follows:
Pad to floor using pressure sensitive glue is 1/16“x1/16“x1/16” square notch; Carpet to pad with a smooth back carpet use a 1/8“x1/16“x1/8” U notch; Carpet to pad with a rough back carpet (Axminster carpet) use a 1/8“x3/16“x1/8” U notch.
The proper roller recommended for a double glue installation is a 35-50 lb. roller. Axminster carpet should be rolled in the length only. After 2-3 hours, the carpet should be rolled again.
Skilled, responsible and competent installers of patterned carpet can effectively adjust within manufacturer tolerances to provide a successful installation. To assist this process, manufacturer tolerances must be clearly understood, communicated and agreed upon by all parties prior to the specification, bid, purchase and installation. Make sure to have additional carpet for successful pattern matching.
Factors affecting an acceptable pattern match include: the method of installation, the condition and levelness of the floor, and the type of carpet backing system selected. It is imperative all parties agree upon realistic levels of expectation before the carpet is installed. Installation of patterned carpet requires more time, expertise and often the use of a power stretcher and additional crew members.
Other things to consider with pattern carpet are:
Roll sequence – Sequence carpet cuts working from the longest measured repeat gradually down the shortest repeat within the dye lot. Roll sequencing information is available from the carpet manufacturer.
Pattern adjustment – Pattern adjustment during installation is possible and should be anticipated.
Pattern alignment – Match the pattern at the midpoint of the seams length. Work from the seam’s midpoint to the seam ends. Bring the pattern into register using appropriate tools, such as: power stretcher, knee kicker, dead man, dry line, stay nails, or crab stretcher.
If required to protect the finished floor covering from soil or paint, or if additional work is to be done after the installation, cover it with a non-staining building material paper. Protect the completed installation from rolling traffic using sheets of hardboard or plywood. Caution: Do not place plastic sheeting over any carpet installation because not only is it a slip hazard, but it may leave a residue that results in rapid soiling after removal. In addition, plastic sheeting may trap moisture, which may promote mold growth, and retard adhesive curing.
Wilton is one of the three major woven carpets. Wilton is also processed on a Jacquard loom as is Axminster carpet, which has a special mechanism to form patterns in the surface pile and place some of the pile yarn on the back.
A high-quality Wilton may be made with 252 pitch and 8 to 10 wires per inch, with a lighter or heavier yarn to provide density. Other combinations of weight, density and pile height provide different carpets with varying performance capabilities. A dense low pile, of a given weight and construction, though will not feel as comfortable under foot.
The loom will also weave Wiltons with sharply delineated sculptured and embossed textures. The pattern effect is achieved by varying the pile height, different wire heights, using a combination of cut and uncut pile, and by using a combination of different yarns.
Stretch-In Installation: Basically, stretch-ins on Wilton would be the same as on the Axminster, with the exception that the Wilton does have stretch in width and length. All edges at seams must be trimmed. Check with the manufacturer as some woven carpet selvages must not be trimmed.
Direct Glue Installation: The minimum trowel notch for direct gluing of Wilton carpet is 1/8“x1/8“x1/8” U notch. All other procedures for a Wilton would be the same as for the Axminster.
Double Glue Installation: This procedure would be the same as for Axminster carpet, except Wilton carpet can be rolled in both directions.
Lastly, remember Axminster, Wilton, Velvet and tufted Wool all have characteristics that do not compare with synthetic carpets, i.e. nylon/polyester.