Duplex Duplex Stainless Steel (British Standards)

The materials, physical design, manufacture and allocated load capacity of our lintels are all governed by relevant British and European Standards, as well as building regulations. Our lintels are designed to comply with the following standards where relevant, even our special or custom designed lintels.

BS EN 845-2: 2013 (at final draft) release now lists both duplex and ferritic stainless steels alongside austenitic stainless steel as acceptable materials for lintel manufacture – we offer all three types, although duplex and ferritic are now generally preferred for lintels.

BS EN 845-2:2003 Specification for ancillary components for masonry - Lintels
This is the primary British standard for lintel design, including steel lintels. It applies to straight lintels up to a maximum of 4.5 meters in length. Our lintels over this length are designed to meet the (extrapolated) requirements of this standard and appropriate structural standards (BS EN 1993-1-1/3) and are designed in accordance with standard structural engineering practice. Note that a new version of BS EN 485-2 is at final draft as of January 2013 and due for release soon.

The expected 2013 release of this standard specifically allows the use of both duplex and ferritic stainless steel for the manufacture of lintels, allowing for stronger, more corrosion resistant and more cost effective stainless steels to be used. Harvey Lintels already manufacture from both high strength duplex and high strength ferritic stainless steels with the associated advantages, although up till not they have not been formally mentioned in the lintel standards.

BS EN 845-1:2003 Specification for ancillary components for masonry - Ties, tension straps, hangers and brackets
We often design and supply more than just the lintel, or design the lintel as an integral part of a steel masonry support system. Elements such as brick ties, straps and hangers may attach directly to some of our special lintels, so it is important that the materials match to minimise corrosion, and that our lintel design ensures the other elements remain compliant with BS EN 845-1.
BS 5977-1:1981 Lintels - Method for assessment of load
This is the most important standard with regard to the calculation of load being applied to a lintel. BS5977-1 is used in the lintel specification process when selecting lintels for particular applications, and also when giving examples of loads that could be applied to a given standard lintel.
BS 5628-1:2005 Code of practice for the use of masonry - Structural use of unreinforced masonry
Governs the design of masonry bearings for lintels. We assume that the supported masonry walls are built in accordance with this standard, and where required, we undertake bearing stress calculations using this standard.
BS 5628-3:2005 Code of practice for the use of masonry - Materials and components, design and workmanship
Our lintels are designed to comply with BS 5628-3 with regard damp control / exclusion of water, movement and structural stability. Unlike concrete lintels, Steel lintels are carefully designed to perform more functions than simply support the masonry, so items such as integrated stop-ends and the slope are designed to meet the moisture control requirements of BS 5628-3. This standard also implies that buildings over 3 stories high or in coastal or aggressive environments should use stainless steel lintels for their corrosion resistance. LDX 2101 is the material we would strongly recommend for these situations, due to its high strength, better corrosion resistance than 304, and comparable, if not cheaper (and more stable) price.
BS 8215:1991 Design and installation of damp-proof courses in masonry construction
Similar to BS 5628, our stainless steel lintels often provide integral DPC elements, so must also comply with BS8215.
BS EN 1991-1-1:2002; General actions - Densities, self-weight, imposed loads for buildings
BS EN 1991-1-3:2003; General Actions – Snow loads
BS EN 1991-1-4:2005; General Actions - Wind actions
When considering special loads applied to lintels, our technical department typically reference the above Eurocodes, together with the national annexes as applicable.  Most standard lintels are designed with appropriate margins of safety in accordance with BS EN 845-2, however in many applications the lintel may support more than just masonry (it may be an integral part of a building frame or supporting an unusual floor load) and so must also comply with the relevant structural codes and the applied loads are calculated with the reference to the above Eurocodes.
BS EN 1993-1-1:2005; Design of Steel Structures – General rules and rules for buildings
BS EN 1993-1-3:2006; Design of Steel Structures – Supplementary rules for cold formed members
BS EN 1993-1-4:2006; Design of Steel Structures – Supplementary rules for stainless steels
The above Eurocodes have now replaced the relevant parts of BS 5950 for lintel design.  Although our standard lintel ranges are all designed to BS 5950, new bespoke designs that do not fall within the scope of existing calculations (or testing) are now generally designed in accordance with the above three Eurocode standards.
BS EN 1993-1-2:2005; Design of Steel Structures – Structural fire design
It is worth noting that some of the stainless steels we manufacture our lintels from retain a significantly greater proportion of their yield strength at elevated temperatures than do standard structural steels.  This can be an advantage to architects and engineers concerned with fire design.  The stainless steels we use have their elevated temperature properties specifically listed in the tables in this standard.  Please contact our technical department for more information on elevated temperature properties.
BS 5977-2:1983 Lintels - Specification for prefabricated lintels
This has now been superseded by BS EN 845-2:2003, but many manufacturer's lintels were designed to this standard. BS 5977-2 may occasionally be referred to in lintel design.
BS 5950-5:1998 Code of practice for design of cold formed thin gauge sections
This is the primary structural steel code to which our standard stainless lintel ranges were designed, together with additional information pertaining specifically to the properties of stainless steels. It is far more applicable to light gauge design than BS449, but has now been withdrawn and superseded by BS EN 1993-1-3&4. Calculation guidelines for web buckling, bearing buckling, bending yield, flange buckling and more are given in BS 5950 and it is frequently referenced, although BS EN 1993-1-4 is more relevant for stainless steel lintels.