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Keystone Box Lintels - Standard/ Heavy/ Extra Heavy Duty

Name: Keystone Box Lintels - Standard/ Heavy/ Extra Heavy Duty
Brand: Keystone Lintels Ltd
SKU: uFp1Z6wfGvyJL3CQLL8fjx

Verified by manufacturer 4 months ago

Keystone Lintels Ltd

Third party certifications:

BBA Agrément Certificate
Certificate type
BS EN 1090-1
Certificate type
ISO 9001 Quality Management
Certificate type

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Application

Box lintels for use in internal and external cavity or solid wall construction to support walls, floors and roofs above window and door openings.
Solid wall construction.
Lintels should be installed with a minimum end bearing of 150 mm, bedded on mortar and levelled along its length and across its width.
The masonry above the lintel should be built in accordance with BS EN 1996-2.
The box lintel is designed to carry the full load of wet masonry as soon as it is installed.
Masonry should be laid on a mortar bed and all perpendicular joints should be filled. Allow the mortar to cure before applying floor or roof loads.
NHBC & LABC recommend a damp proof course (DPC) or cavity tray should be installed over all openings in external cavity walls.
When installing concrete floor units or other heavy components above a lintel, care should be taken to avoid shock loading and floor units should not be dragged into position. Masonry immediately above the lintel should be allowed to cure.
Point loads should not be applied directly onto lintel flanges. Lintels should have a minimum of 150 mm masonry between the flange and the application level of any form of loading. Consult Keystone’s Technical Department if applying a point load above a lintel.
Do not cut lintels to length or modify them in any way without consulting a Keystone engineer.
Masonry should not overhang any flange by more than 25 mm.
Stop ends are required at each end of a lintel to prevent moisture cascading over the ends into the cavity and onto the inside wall.
At least two weep vents are required per opening and positioned not more than 450 mm apart.

Description

All Keystone box lintels satisfy the thermal performance requirements of Approved Document L of the Building Regulations (E & W), Northern Ireland’s Technical Booklet F and Scotland’s Technical Handbook, section 6. The Keystone box lintel has perforations along its length acting as a plaster key. Keystone box lintels can be insulated.

In external walls provide a damp proof course / cavity tray over all lintels. For more detailed information applicable to a particular wall construction, contact Keystone Lintels Technical Department.

Refer to manufacturers literature for details regarding lintel ranges, height, thickness and Uniformly Distributed Load (UDL) figures.

Performance:

Fire:

Keystone lintels have been subjected to a fire test (WARRES No. 101263) in accordance with BS 476-20 and (Report No. 508704/R) in accordance with BS EN 1363-1 at Exova Warrington Fire and achieved a one hour fire performance.

Corrosion:

Keystone’s box range of lintels are manufactured from high quality grade pre-galvanized mild steel to BS EN 10346 DX51D with a zinc coating conforming to BS EN 845-2.
The use of austenitic stainless steel is ideal when the life expectancy and maintenance programme of a building are key considerations.
Material / coating specification in buildings exceeding three storeys in a non-aggressive environment should be limited to austenitic stainless steel (chrome nickel alloys).
Material / coating specification for buildings in an aggressive environment (e.g. coastal sites) should be limited to austenitic stainless steel (molybdenum chrome nickel alloys).

Structural:

The Keystone lintel range has safe working loads as detailed in each applicable loading table in the Keystone Steel Lintel Manual.
The structural performance figures within each table have been ascertained by testing in accordance with the requirements of standards BS EN 5977-2, BS EN 846-9 and BS EN 845-2.

Certification:

BBA Agrement certificate 98/3493 including regular assessment of production.
UKCA Assessment of performance, System 3.
CE Assessment of performance, System 3.
EN 1090-2 Execution Class 2, Declaration method 1,2,3a & 3b, Certificate 14/F106 & 14/F107.
ISO 9001 Quality Management Systems, Certificate 18/Q059.
ISO 14001 Environmental Management Systems, Certificate 18/E019.

Special lintels:

Keystone lintels can be supplied to suit a wide range of wall types, loading scenarios and bespoke custom made specials:

Arch lintels,
Bay lintels (square or splayed),
Corner lintels,
Bow lintels,
Sunlounge lintels.

Contact Keystone Lintels Technical Department for further information.

Stainless steel:

All Keystone’s range of lintels can be manufactured from austenitic stainless steel, grade 304 2b BS EN 10088-Part 2 Astm 240 (European Grade 1.4307).
Upon request, other grades of stainless steel lintels are available conforming to BS EN 845-2.

Additional features:

Free scheduling and specification service.
Keystone Steel lintels have a service life commensurate with that of the building in which they are installed.
Feature plate.
Powder coating.
Soffit cladding.
Brick slip cladding.
Universal arch.
Weep holes.
Stop ends.
Bespoke.

Contact Keystone Lintels Technical Department for further information

General information

Color	Silver
Finish	Galvanized Powder-coated
Material	Steel Guidance for specification option: Pre-galvanized mild steel to BS EN 10346 DX51D with a zinc coating of 600 g/m² (including both sides). Material Coating Ref L14. Pre-galvanized mild steel to BS EN 10346 DX51D with a zinc coating of 275 g/m² (including both sides). Stainless steel Guidance for specification option: Austenitic stainless steel, grade 304 2b BS EN 10088-Part 2 Astm 240 (European Grade 1.4307) Material Coating Ref L3. Austenitic stainless steel, grade 316 2b BS EN 10088-Part 2 Astm 316/316L (European Grade 1.4404) Material Coating Ref L1.
Length	- Manufacturer guidance Refer to Keystone Steel Lintel Manual or contact Keystone Lintels Technical Department.

Uniclass	Pr_20_85_48_11 Carbon steel lintelsPrimary Pr_20_85_48_84 Stainless steel lintels
CAWS	F30/755 Prefabricated steel lintels F30/85 Prefabricated steel lintels

Specification data - Carbon steel lintels

Standard	To BS EN 845-2. Guidance for specification option: UKCA and CE Marked to BS EN 845-2 Specification for ancillary components for masonry Part 2: Lintels. Manufacturer guidance Declaration of Performance certificates are available at: www.keystonelintels.com.
Lintel type	Composite.
Material finish and coating reference	Pre-galvanized mild steel to BS EN 10346 DX51D with a zinc coating of 600 g/m² (including both sides). Material Coating Ref L14. Pre-galvanized mild steel to BS EN 10346 DX51D with a zinc coating of 275 g/m² (including both sides). Austenitic stainless steel, grade 304 2b BS EN 10088-Part 2 Astm 240 (European Grade 1.4307). Material Coating Ref L3. Austenitic stainless steel, grade 316 2b BS EN 10088-Part 2 Astm 316/316L (European Grade 1.4404). Material Coating Ref L1.
Sizes	As Lintels schedule.
Characteristics	-
Resistance to fire	Minimum period of 60 minutes, consult Keystone Lintels Technical Department.
Thermal conductivity	Part L compliant.

Duty	Standard duty. Heavy duty. Extra heavy duty.
Accessories	Not required. Keying options to suit required plastering applications. Feature plate. Powder coating. Soffit cladding. Brick slip cladding. Universal arch. Weep holes. Stop ends. Bespoke. Guidance for specification option: Contact Keystone Lintels Technical Department for further information. Show more