XPS 700 W
Heat-treated state · default condition
EN 13164 XPS700 · GB GB/T 10801.2 XPS700
W = 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.
Values for the W 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 | — |
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 | — |
WDefaultThis page 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 W?
XPS 700 W is XPS 700 heat treated to W — default high-load board: smooth skin gives the lowest thermal conductivity and lowest water uptake, used for floors, roadbeds and cold-store floors. XPS 700 W has a tensile strength of 0.65 MPa (0.0943 ksi), weaker than 86% of polymer grades. Elongation at break is 3% and the elastic modulus is 0.03 GPa (0.0044 Msi). XPS 700 W 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).
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 (0.0173 BTU/hr·ft·°F), worse than 96% of polymer grades
- Degrades in UV without stabilisers — 15/100, worse than 95% of polymer grades
- Limited ductility — 3%, worse than 83% of polymer grades
XPS 700 W properties
Typical room-temperature values for XPS 700 W; 15 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 W 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 W has a tensile strength of 0.65 MPa (0.0943 ksi), weaker than 86% of polymer grades. Elongation at break is 3% and the elastic modulus is 0.03 GPa (0.0044 Msi).
Thermal9
XPS 700 W is rated for continuous service to 75°C (167 °F). It conducts heat at 0.03 W/m·K (0.0173 BTU/hr·ft·°F), worse than 96% of polymer grades. Thermal expansion is 70 µm/m·K (38.9 µin/in·°F).
Electrical4
XPS 700 W has an electrical resistivity of 1×10¹⁴ Ω·m.
Chemical & Environmental2
UV resistance is poor.
Sustainability4
Producing a kilogram of XPS 700 W 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 W's machinability is excellent (90/100, better than 95% of polymer grades); weldability poor (20/100); formability poor (25/100).
Common Calculations4
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with XPS 700 W
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 W — frequently asked
What is XPS 700 W used for?
XPS 700 W 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 W?
XPS 700 W has a typical tensile strength of 0.65 MPa (0.0943 ksi) — weaker than 86% of polymer grades. Strength varies by condition: see the 6 listed tempers.
Is XPS 700 W 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 W 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 W?
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 W 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 W?
XPS 700 W 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.