Nylon carpet installed runs $3 to $7.50 per sq ft, covering material, pad, and labour. Nylon is the durability benchmark in synthetic residential carpet: it bounces back from compression where polyester gives up, it cleans well, and a properly specified nylon install lasts 15 to 20 years. The spec choice that matters most is not the brand; it is Type 6,6 vs Type 6, and solution-dyed vs piece-dyed. Get those right and almost any major-brand mid-grade nylon will serve you well.
Nylon carpet comes in two chemically distinct forms, and the distinction is almost never explained on the dealer floor. Type 6 nylon is made from a single monomer (caprolactam) and has a less dense molecular structure. Type 6,6 nylon is made from two monomers (adipic acid and hexamethylenediamine) and has a denser, more crystalline structure that resists compression and stains better. The performance difference is real but subtle. Type 6,6 nylon retains roughly 90 percent of its original pile height after 10 years of typical residential use; Type 6 retains about 75 percent over the same period. For low-traffic rooms (guest bedrooms, formal living rooms) the difference is not noticeable. For high-traffic rooms (family rooms, hallways, kids' bedrooms) Type 6,6 visibly outlasts Type 6.
The cost premium for Type 6,6 over comparable Type 6 is typically 15 to 25 percent on the same construction (same face weight, same pile height, same backing). On a 1,000 sqft install, that is roughly $400 to $700 of carpet material cost. Spread across the additional 4 to 6 years of useful life that Type 6,6 typically delivers, the cost per year of service is lower for Type 6,6 in any meaningful-use room. Mohawk Wear-Dated, Stainmaster, and Karastan are all Type 6,6 brands; Shaw runs both Type 6 and Type 6,6 depending on line; budget no-name nylons are almost always Type 6.
The second meaningful nylon-spec decision is the dye method. Solution-dyed nylon has the colour incorporated into the nylon polymer before the fibre is extruded. The colour goes through the entire cross-section of every strand. This has three practical benefits. The carpet does not fade in sunlight, which matters in west-facing or south-facing rooms that get strong afternoon sun. The carpet does not lose colour when cleaned with strong oxidising stain removers (bleach, hydrogen peroxide), which means stains can be aggressively treated without ruining the colour. And the carpet has built-in stain resistance because there is no dye chemistry on the fibre surface for stains to bond to.
Piece-dyed nylon has the colour applied to the spun fibre as a surface coating, typically after the carpet is tufted. It is cheaper to manufacture, which is why most budget nylon carpets are piece-dyed. The downsides mirror the solution-dyed benefits: more sun fade, more colour loss when stain-cleaned aggressively, and less inherent stain resistance. The solution-dyed premium over piece-dyed is 15 to 25 percent on the same construction, well worth it for any carpet expected to serve 10+ years.
The stain warranties advertised on nylon carpet (lifetime stain, 20-year stain, 10-year stain) are real but narrowly defined. They cover specific water-based household stains (coffee, juice, soft drinks, milk, urine if cleaned promptly) for the stated period. They do not cover bleach-based dye loss (laundry chemicals, hair dye, acne medication, some household cleaners), oil-based stains (cooking oil, motor oil, asphalt), or stains left untreated beyond a stated window, typically 24 to 48 hours. They also typically require documented professional cleaning every 12 to 24 months to remain valid; many homeowners do not realise this and find out only when they try to make a claim. Read the actual warranty document at purchase, set a calendar reminder for the next professional cleaning, and keep the receipts in a folder with the carpet documentation. A typical professional cleaning runs $0.30 to $0.50 per sqft, so $300 to $500 for a 1,000 sqft install every 18 months. That is the real annual cost of keeping the warranty valid, and it is the same number regardless of brand.