Fire resistance time
Steel heating under the fire curve, the time to reach the critical temperature and the fire resistance class achieved, from R 30 to R 240.
FireSolver
Fire design · EN 1993-1-2
Critical temperature of steel members.
Checks for tension, compression, bending and shear, and combined compression and bending, including flexural buckling and lateral-torsional buckling. The results include the fire resistance time, the fire resistance class achieved and the required protection thickness, with an optional PDF report.
Free online calculator, no account needed. Create an account to save your projects.
App features
Fire curves
The standard ISO 834 curve, the hydrocarbon and external fire curves, and your own user-defined curve.
Fire protection
The protection thickness required for the target fire resistance class, with the section factor Am/V determined automatically.
Custom exposure
Definition of the surfaces exposed to fire and of the protected surfaces, including partial exposure and special geometries.
Automatic stability parameters
Automatic determination of the buckling lengths and of the elastic critical moment Mcr, for the configurations covered by the implemented methods.
Section catalogue
HEA, HEB, HEM, IPE, IPN and circular, square and rectangular hollow sections (CHS, SHS, RHS), steel grades S235-S460.
Projects and members
Checks are saved individually, and structural members can be organised and grouped by project.
PDF reports
A report for each member and a summary report for the project, ready to attach to the technical documentation.
Critical temperature for every type of loading
FireSolver checks steel members for the load cases it implements, including instability effects. Depending on the member type and the load case, the app determines the critical temperature with the corresponding calculation method.
Tension
EN 1993-1-2 §4.2.3.1The critical temperature is determined from the degree of utilisation of the section.
Compression
EN 1993-1-2 §4.2.3.2Flexural buckling check about both axes of the section, with the buckling lengths and the reduction of steel strength at elevated temperature.
Bending and/or shear
EN 1993-1-2 §4.2.3.3-4.2.3.4Bending check, including lateral-torsional buckling and the interaction between bending moment and shear force.
Compression with bending and/or shear
EN 1993-1-2 §4.2.3.5Check of the interaction between axial force and bending moments, with the instability effects required by the applicable calculation method.
The calculations are checked against worked examples from the published literature and more than 10,000 automated test cases. See the validation of the calculations
How it works
- 1
Define the member
Choose the section, the steel grade and the number of sides exposed to fire.
- 2
Enter the loads
Design actions in the fire situation and the required class.
- 3
Get the result
Fire resistance time, the check and the PDF report.
Guides
Fundamentals
Cross-sections and protection
Frequently asked questions
How are the calculations checked?
We recalculated the worked examples of three published references on EN 1993-1-2, mainly the book "Fire Design of Steel Structures" by J.-M. Franssen and P. Vila Real. Besides them, more than 10,000 automated test cases check the calculation engine every week. Validation against published literature
Which standards does FireSolver use?
Calculations follow EN 1993-1-2 and EN 1993-1-1 for steel members, with thermal actions from EN 1991-1-2.
Do I need an account?
No. The calculator is free and works without an account. Create an account to save your projects and checks.
Do I need to install anything?
No. The app runs in the browser, on a computer or tablet; projects are saved to your account and available on any device.
Where is my data stored?
On servers in the European Union (Frankfurt), as described in the privacy policy.
