Join two carpet offcuts into one neat, flat seam using heat-activated tape, without lumps or gaps showing.
JC-01Clear the area and check the carpetMove furniture off the area and roll back both pieces of carpet. Check the pile direction on each piece — run your hand over it, it should feel smooth one way and rough the other. Both pieces must have the pile running the same way or the seam will show as a visible line.
JC-02Choose your joining methodFor most domestic jobs, heat-activated carpet seam tape and a seaming iron give the flattest, strongest join. Carpet seam adhesive (a strong tacky glue) is a slower but simpler option if you don't want to hire an iron. Tape is better for busy areas like hallways; adhesive is fine for a spare room or under furniture.
1 roll · Heat-activated carpet seam tape 1 each · Seaming iron (hire, per day) 1 tube · Carpet seam adhesive (alternative to tape) JC-03Dry-lay the two pieces and align the patternOverlap the two edges by about 20-30mm and lay them flat, pile facing up. Line up any pattern or weave so it runs continuously across the join. Push a few pins or heavy books along the overlap to hold it in place while you check the fit.
JC-04Cut a straight, tight seam edgeUse a steel straight edge and your utility knife to cut through both layers at once, following the weave lines on the backing as a guide. Cut from the backing side where possible for a cleaner line. This gives you two edges that will sit tight together with no gap and no overlap.
1 each · Steel straight edge 1 pack of 5 · Utility knife blades JC-05Position the seam tape underneathSlide the seam tape centrally under the join, adhesive side up, so half sits under each carpet edge. Push both edges down onto the tape so they meet exactly, pile touching pile with no gap. Double-check the pattern and pile direction still line up before you apply heat.
JC-06Heat the tape and press the seam togetherSet the seaming iron to a medium heat and run it slowly along the tape, about 300mm at a time, letting the adhesive melt. Lift the iron and immediately press the carpet edges down firmly into the melted tape, working along the seam before it cools. Keep the pile pushed together as you go so no backing shows through.
JC-07Weight the seam while it coolsPlace heavy books, tins, or a roll of carpet along the full length of the seam and leave it for at least 15-20 minutes to cool and bond fully. Don't walk on the seam or pull at it while it's still warm, as this weakens the bond.
JC-08Check the join and tidy upRun your hand across the seam — it should feel flat with no ridge, gap, or fraying edge. Fluff the pile back up with your fingers or a carpet brush to blend the join. Sweep up any offcuts and fibres, and put furniture back once the seam has fully cooled.
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