Earthbag construction stacks soil-filled polypropylene or burlap bags, bonded with barbed wire between courses and tamped solid before plastering. Using a handheld bag-closer—like the Newlong NP-7A, Newlong Industrial NP-8 or NP3ii seals bags with a durable single-thread or double chain stitch, drastically speeding up building compared to hand-folding or pins.
Construction Steps
- Foundation & Trench: Dig a 18–24″ trench, fill with compacted gravel, and lay two gravel-filled bag courses to prevent capillary moisture draw.
- Mix & Fill Bags: Blend subsoil (10–30% clay) with damp water to pass a squeeze test. Fill bags 75–80% full.
- Stitch Mouths: Pull bag tops flat and run a portable sewer (Eurosew NP-7A, EZGO 101, or NP-3II) across the edge for a tight, 2–3 second seal that survives tamping.
- Lay Bags & Barbed Wire: Place stitched bags end-to-end. Lay two strands of 4-point barbed wire between every course to lock rows against lateral forces.
- Tamp & Stagger: Pound bags flat with a hand tamper until solid, staggering vertical seams like brickwork for each row.
- Bond Beam & Plaster: Pour a reinforced concrete bond beam over the top course for roof load distribution. Apply lime or earth-cement plaster immediately to protect polypropylene from UV damage.
Portable Machine Guide
- Newlong Industrial NP-7A: Industry-standard, heavy-duty closer with an automatic thread cutter for high-volume daily site work. Use it with for Example P15 350 DTEX geotextile thread.
- Newlong Industrial NP-3ii: Lightweight, cordless/battery-friendly model best for off-grid sites without power generators. Use it with for Example P15 350 DTEX geotextile thread.
