Buy woven or nonwoven geotextile against the project’s required performance, not a universal strength-versus-permeability rule. Woven constructions include tapes, monofilaments and multifilaments; nonwoven products also vary by polymer and manufacturing process. Compare the actual grade, test method, direction, hydraulic conditions and acceptance basis before comparing price.
This article focuses on quotation and submittal comparison. For soil-filter design, use the drainage selection guide; for a traffic-bearing aggregate surface, use the gravel-road guide. Neither appearance nor nominal GSM is sufficient evidence for substitution.
Define the purchase by function
| Required function | Compare first | Do not assume |
|---|---|---|
| Separation beneath aggregate | Soil retention, installation survivability and the specified material class | Any woven fabric supports any truck, or any nonwoven is unsuitable for roads |
| Drainage filtration | Opening size, water passage, soil compatibility and clogging resistance | All woven fabrics have low flow or higher GSM always filters better |
| Reinforcement | Tensile response, strain limits and long-term design strength | Grab breaking force is an allowable structural load |
| Geomembrane protection | Protection performance with the actual liner, aggregate and loading | A nominal fabric weight guarantees resistance to every sharp object |
Read strength results on the same basis
ASTM D4632/D4632M is a grab breaking-load and elongation index test. Its public scope cautions against broad comparisons across different fabric structures and against using it as the only design information. ASTM D4595/D4595M addresses wide-width tensile behavior. Do not convert a grab load into kN/m merely by dividing by a convenient width.
For unit conversion only, 200 lbf is about 890 N, and 315 lbf is about 1,401 N. These are forces measured under a specified test, not truck capacities. A marketing grade name such as “200W” is not a substitute for a report. Check machine and cross-machine directions separately; a strong result in one direction does not cancel a shortfall in the other.
Separate typical values, minimum average roll values, maximum limits and individual test results. Ask which basis the purchase specification requires, how sampling is conducted and how nonconforming lots are handled. The word “minimum” on a quotation is incomplete without the test and acceptance basis.
Compare hydraulic performance without treating flow as filtration
Higher laboratory water flow does not establish better retention of the project soil. A suitable woven monofilament filter can combine useful strength and hydraulic performance; there is no universal rule that manufacturing cannot deliver both. Conversely, a tight road-separation fabric may be unsuitable for a specified drain.
ASTM D4491/D4491M addresses water permeability by permittivity under defined laboratory conditions. Compare head, conditioning and units. Permittivity is expressed in s−1, whereas hydraulic conductivity uses a length/time unit. Neither alone gives the capacity of a soil-filter-pipe system.
As a calculation example, 140 US gal/min/ft² is approximately 5,704 L/min/m², and 5 US gal/min/ft² is approximately 204 L/min/m². The ratio is 28, not 35. These illustrative numbers are not Jinseed product ratings. An incoming 300 US gal/hour is 5 US gal/min total; it cannot be compared directly with a flow rate per square foot without area and compatible test conditions.
Check apparent opening size and soil compatibility alongside flow. A 0.150 mm opening is larger than a 0.075 mm particle; it cannot be described as a simple sieve that necessarily stops every such particle. Actual soil-filter behavior, including clogging, requires the specified assessment. A geotextile is not automatically a root barrier or a wastewater-treatment system.
Reconcile roll area, fabric mass and delivered cost
A 12.5 ft × 300 ft roll has a gross area of 3,750 ft² or 416.67 yd². At a stated 8 oz/yd², dry fabric mass is 416.67 × 8 ÷ 16 = 208.33 lb, approximately 94.5 kg. A 350 lb gross roll would need an explanation such as different dimensions, actual mass or packaging; it does not follow from those stated dimensions and GSM alone.
| Illustrative offer | Gross fabric cost | Interpretation |
|---|---|---|
| $120 per 416.67 yd² roll | $0.288/yd² | Before freight, taxes, handling, laps and waste |
| $180 per 416.67 yd² roll | $0.432/yd² | Same exclusions; not a current Jinseed price |
| 10% of purchased area unavailable for net coverage | Gross unit cost ÷ 0.90 | 11.1% higher cost per covered unit, not 10% |
For the original aggregate-loss example, 1 inch across 1,000 ft² is 83.33 ft³. At an assumed 120–150 lb/ft³ bulk density, this represents 5.0–6.25 US short tons. It is a quantity sensitivity calculation, not proof that a fabric will save that amount in service.
Check durability and construction limitations
Request polymer identification, exposure limits and durability evidence relevant to the actual temperature and chemistry. A laboratory UV test duration cannot be converted into a universal number of uncovered site days. Neither black color nor a broad pH claim establishes a 20- or 50-year service life.
Specify laps or seams, subgrade preparation, cover and equipment access from the approved design. Do not drag fabric across stumps, turn excavator tracks on bare fabric or assume that an index puncture result permits uncontrolled aggregate dumping. For drains, preserve maintainable outlets rather than tying off discharge ends.
What to include in a comparable quotation request
- Application drawing, soil information, loading and intended function.
- Required polymer and construction, where specified.
- Test methods, units, directions, acceptance values and specification edition.
- Roll dimensions, net coverage plan, delivery sequence and handling constraints.
- Traceable reports, sampling requirements and the authority approving any substitution.
Review available nonwoven geotextile information, then request a quotation against the complete specification. If a woven construction is mandatory, a nonwoven alternative requires explicit technical and contractual approval.
