What to buy: adhesive traits that last on concrete
Concrete moves with temperature and moisture. The right turf adhesive needs to bite into a mineral surface, stay flexible, and shrug off water and UV. Look for these traits on the label.
- Polyurethane or urethane chemistry that moisture cures
- Exterior and wet service rating with waterproof bond
- High green strength to resist curl and creep during set
- Remain flexible after cure to handle expansion and contraction
- UV and temperature resistance suitable for sun-exposed slabs
- VOC compliant in your state and freeze thaw stable
One part vs two part
One part moisture curing products are the pro standard for most turf over concrete. They are easy to gun or trowel and cure with ambient humidity. Two part systems are specialty options for extreme loads or low humidity environments and require accurate mixing.
Trowel grade vs cartridge beads
Trowel grade is best for wide areas, perimeters, and under seam tape. Cartridges are efficient for linear seams and spot bonding. Most installs use both.
Surface prep that makes glue count
- Clean. Remove paint overspray, curing compounds, sealers, grease, dust, and loose particles. Grind or shotblast glossy or sealed areas. Vacuum thoroughly.
- Repair. Patch cracks or spalls. The slab must be sound, flat, and dry to the touch.
- Check moisture. Avoid active moisture issues or hydrostatic pressure. A simple plastic sheet test should show no condensation after 24 hours. If in doubt, consult a concrete moisture test.
- Dry fit the turf. Unroll, relax wrinkles, and let materials acclimate 1 to 3 hours. Plan seam locations and edge terminations.
- Prime dusty surfaces if needed. On very porous or chalky concrete, use the adhesive manufacturer approved primer to improve bond.
Ensure drainage pathways remain open. Slabs should shed water away from structures. Do not trap water under the system.
Application: a proven bond pattern
- Seams first. Place seam tape shiny side down. Trowel a thin, even coat of adhesive on the tape, keeping 1 inch clear at edges to control squeeze out. Marry the turf edges with consistent gauge separation. Roll the seam with a carpet roller and weight until set.
- Perimeter next. Trowel a continuous band 4 to 6 inches wide around the perimeter. For cartridges, run 3 to 8 parallel beads depending on edge width. Press the turf into the wet adhesive for full contact.
- Field area. For drainage, apply adhesive in interrupted ribbons or a serpentine pattern at 6 to 12 inch spacing rather than full coverage. Maintain adequate contact without creating a vapor barrier.
- Roll and weight. Use a 50 to 75 lb roller or heavy tamp to seat the turf. Sandbags or weights on seams and edges control lift during cure.
- Cure. Respect open time and set time on the pail or tube. Typical walk on is 24 hours. Full cure is often 24 to 72 hours depending on temperature and humidity.
Coverage and timing benchmarks
- Trowel grade with 1/8 inch V notch: about 60 to 100 sq ft per gallon
- Seam beads from 10 to 11 oz cartridge: about 20 to 30 linear feet
- Open time: about 20 to 45 minutes
- Install temperature window: about 40 to 100 F, avoid extremes
Always follow the specific product data sheet for spread rate and cure schedule.
Climate and use considerations
- Heat and sun. Choose an adhesive rated for high surface temperatures. Dark slabs can run hot in peak sun.
- Freeze thaw. Flexible bonds handle movement better. Avoid installing below the minimum temperature or on frozen surfaces.
- Rooftops and waterproof membranes. Verify chemical compatibility with membranes and never block drains. Use protection boards where required.
What not to use on concrete
- Indoor only carpet glues and water based latex mastic for exterior slabs
- Generic construction adhesives not specified for turf or exterior concrete
- Hot melt glue or pressure sensitive tape for permanent outdoor installs
- Epoxies without flexibility can become brittle under thermal cycling
Edge restraint and transitions
Secure the perimeter to stop lift and trip hazards. Bond turf to approved metal or composite edging adhered to the slab, or run a continuous perimeter trowel band. Keep transitions to pavers or thresholds flush and well bonded.
Safety and cleanup
- Ventilate. Wear gloves and eye protection.
- Keep away from flame. Many solvents are flammable before cure.
- Clean uncured residue with manufacturer approved solvent. After cure, remove mechanically.
Troubleshooting
- Edge lift. Add perimeter adhesive and weight until cured. Confirm the surface was clean and dry.
- Seam peaking. Reduce tension across the seam and roll. Do not overfill the seam with adhesive.
- Slow cure. Low temperature and low humidity slow moisture curing. Allow more time or gently increase ambient conditions within product limits.
Quick spec checklist for the purchase aisle
- Moisture curing polyurethane or urethane
- Exterior use, waterproof, flexible after cure
- Compatible with concrete, synthetic turf backing, and seam tape
- Listed open time, cure time, and application temperature range
- Coverage rates for trowel and bead applications
- VOC compliance and freeze thaw stability
