XPS 700 GR
Additive grade
EN 13164 XPS700 · GB GB/T 10801.2 XPS700
GR = graphite-enhanced (IR-absorber modified) high-load board
Use when the 700 kPa strength class must also hit the lowest available λ for thin build-ups; grey board, slightly more brittle.
Values for the GR condition
Other XPS 700 grades and fills
XPS 700 is listed in 6 conditions; see the grade overview at XPS 700.
Compare all 6 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Normalized | Pick when render, plaster or adhesive mortar must bond directly to the foam; accepts slightly higher λ and water absorption. | 0.45 | 0.5 | 2.5 | — |
CO₂-blown / HCFC-free board | Choose for low-GWP or green-building credit projects; slightly higher initial λ than HFC-blown board but no blowing-agent drift penalty. | — | 0.55 | 2.5 | — |
B1 flame-retardant board | Mandatory FR level for most building envelope and public-works uses in China; higher FR loading, marginally lower strength. | — | 0.58 | 2.8 | — |
GRThis page Graphite-enhanced (IR-absorber modified) high-load board | Use when the 700 kPa strength class must also hit the lowest available λ for thin build-ups; grey board, slightly more brittle. | — | 0.58 | 2.5 | — |
B2 flame-retardant board | Economy FR level for buried/covered structural fill and roadbed work where fire class B2 is accepted. | — | 0.6 | 3 | — |
WDefault Solution heat treated (unstable) | Default high-load board: smooth skin gives the lowest thermal conductivity and lowest water uptake, used for floors, roadbeds and cold-store floors. | — | 0.65 | 3 | — |
What is XPS 700 GR?
XPS 700 GR is XPS 700 in the GR grade — use when the 700 kPa strength class must also hit the lowest available λ for thin build-ups; grey board, slightly more brittle. XPS 700 GR has a tensile strength of 0.58 MPa (0.0841 ksi), weaker than 87% of polymer grades. Elongation at break is 2.5% and the elastic modulus is 0.03 GPa (0.0041 Msi). XPS 700 GR has a density of 0.05 g/cm³ (0.0017 lb/in³), lighter than 89% of polymer grades. Its glass-transition temperature is 100°C (212 °F). W is the default condition FabDigit quotes; GR is available on request or by drawing note.
Advantages
- Easy to machine — 90/100, better than 95% of polymer grades
- Lightweight — 0.05 g/cm³ (0.0017 lb/in³), better than 89% of polymer grades
Limitations
- Poor heat conductor — 0.03 W/m·K (0.0162 BTU/hr·ft·°F), worse than 99% of polymer grades
- Degrades in UV without stabilisers — 15/100, worse than 95% of polymer grades
- Limited ductility — 2.5%, worse than 89% of polymer grades
XPS 700 GR properties
Typical room-temperature values for XPS 700 GR; 16 are specific to this condition. Other listed values are XPS 700 reference data and may not represent this condition. Bars are the position among polymer grades.
Physical4
XPS 700 GR has a density of 0.05 g/cm³ (0.0017 lb/in³), lighter than 89% of polymer grades. Its glass-transition temperature is 100°C (212 °F).
Mechanical9
XPS 700 GR has a tensile strength of 0.58 MPa (0.0841 ksi), weaker than 87% of polymer grades. Elongation at break is 2.5% and the elastic modulus is 0.03 GPa (0.0041 Msi).
Thermal9
XPS 700 GR is rated for continuous service to 75°C (167 °F). It conducts heat at 0.03 W/m·K (0.0162 BTU/hr·ft·°F), worse than 99% of polymer grades. Thermal expansion is 70 µm/m·K (38.9 µin/in·°F).
Electrical4
XPS 700 GR has an electrical resistivity of 1×10¹² Ω·m.
Chemical & Environmental2
UV resistance is poor.
Sustainability4
Producing a kilogram of XPS 700 GR takes about 100 MJ of energy and emits 6.5 kg of CO₂ — less than 61% of polymer grades. Typical recycled content is 15%.
Manufacturability3
XPS 700 GR's machinability is excellent (90/100, better than 95% of polymer grades); weldability poor (20/100); formability poor (25/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with XPS 700 GR
Is XPS 700 easy to machine?
Cuts cleanly with hot wire, hot knife, fine-tooth band saw or CNC router at high feed; keep tools cool to avoid melt smear and use dust extraction.
Can XPS 700 be welded?
No practical structural welding; joints are shiplap/tongue-and-groove plus PS-compatible (solvent-free) adhesive or mechanical fixings.
Can XPS 700 be formed, bent or molded?
Supplied as extruded board only — thickness and edge profile (square edge, shiplap or tongue-and-groove) are set on the extrusion line; field shaping is by cutting, not forming.
What surface finishes work on XPS 700?
Skin must be planed, grooved or primed for mortar/plaster adhesion; protect from UV and from solvent-borne paints, bitumen and expanded-polystyrene-attacking adhesives.
XPS 700 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| blowing agent (CO2 / HFC-152a / HFO, resresidual gas in closed cells; determines aged λ | 1 – 5 | 3 |
| flame retardant (polymeric brominated FRlevel set by GB 8624 B1 or B2 target | 0.5 – 3 | 1.5 |
| nucleating agent (talc)controls cell size | 0.2 – 1 | 0.5 |
| pigment / IR absorber (graphite, carbon only in graphite-enhanced grades | 0 – 2 | 0 |
| polystyrene (styrene homopolymer resin)GPPS, optionally with recycled PS regrind | ≥ 90 (balance) | — |
XPS 700 GR — frequently asked
What is XPS 700 GR used for?
XPS 700 GR is typically used for airport pavement insulation, heavy structural fill, load-bearing under-slab insulation for industrial floors, road and bridge approach frost protection, dock, ramp and deck insulation and cold store floor insulation. In short: strongest standard XPS grade; 700 kPa load class; structural fill insulation.
What is the tensile strength of XPS 700 GR?
XPS 700 GR has a typical tensile strength of 0.58 MPa (0.0841 ksi) — weaker than 87% of polymer grades. Strength varies by condition: see the 6 listed tempers.
Is XPS 700 GR easy to machine?
Yes — machinability is rated excellent (90/100, better than 95% of polymer grades). Cuts cleanly with hot wire, hot knife, fine-tooth band saw or CNC router at high feed; keep tools cool to avoid melt smear and use dust extraction.
Can XPS 700 GR be welded?
Not readily — weldability is rated poor (20/100). No practical structural welding; joints are shiplap/tongue-and-groove plus PS-compatible (solvent-free) adhesive or mechanical fixings.
What surface finishes work on XPS 700 GR?
Skin must be planed, grooved or primed for mortar/plaster adhesion; protect from UV and from solvent-borne paints, bitumen and expanded-polystyrene-attacking adhesives.
Can XPS 700 GR be formed, bent or molded?
Supplied as extruded board only — thickness and edge profile (square edge, shiplap or tongue-and-groove) are set on the extrusion line; field shaping is by cutting, not forming.
What is the maximum service temperature of XPS 700 GR?
XPS 700 GR is rated for continuous use to about 75°C (167 °F), and briefly to 85°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between XPS 700 W and XPS 700 N?
W is the default condition — default high-load board: smooth skin gives the lowest thermal conductivity and lowest water uptake, used for floors, roadbeds and cold-store floors. N: pick when render, plaster or adhesive mortar must bond directly to the foam; accepts slightly higher λ and water absorption.
Sources
- ASTM C578 Standard Specification for Rigid, Cellular Polystyrene Thermal Insulation — ASTM (2022)
- STYROFOAM HIGHLOAD 100 / FOAMULAR 1000 high-load XPS technical data — DuPont Performance Building Solutions / Owens Corning (2023)
- Handbook of Polymeric Foams and Foam Technology (polystyrene foam chapters) — Hanser (2004)
- CES EduPack / ICE embodied energy and carbon data for XPS foam — Granta / Univ. of Bath (2019)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.