MetaSlate, Imitation Slate Roofing Sheets | Steadmans Steel Cladding and Roofing

Application

Meta Slate is an innovative steel slate effect roofing material. It is used in a wide and varied range of applications including industrial buildings, offices, shops and showrooms and residential properties. Due to its unique slate effect appearance it has been approved for use on listed and historic buildings where a product that is required to blend in with traditional roofing materials has been required.

Meta Slate provides an alternative to traditional roof finishes and due to its light weight, ease of application and custom sheet sizes it can be used in a wide range of situations and fitted in a time efficient manner. Meta-SlatePlus is a combination of Meta Slate with Steadmans AS35 insulated panels, which are available in a range of thicknesses, giving a high performance roof coverage system with a traditional appearance.

Specifications

Meta-Slate Roofing Sheets are manufactured in a process certified to ISO 9001:2008.

LPCB

INSTALLATION WARRANTY

Steadmans offer an independent audit-based warranty for the Meta-Slate Roofing Systems. The QA+ warranty, from Auditing Workshop & Materials Ltd., provides pre-site and on-site quality inspections and audits to ensure the high standards of construction and finishing which will maximise service life and reduce maintenance costs.

The QA+ warranty can be extended to a ten year insurance backed warranty covering defects arising from poor workmanship, defective materials and damage resulting from design defects. Contact Steadmans for more information about the warranties.

• Approved Documents
- A Structure
- B Fire safety
- C Site preparation and resistance to contaminants and moisture.
- L2A Conservation of fuel and power in new buildings other than dwellings.
- L2B Conservation of fuel and power in existing buildings other than dwellings.
The Scottish Building Standards: Technical Handbook.
- Non-domestic.
BS 476 Fire tests on building material and structures.
- BS 476-3:2004 Classification and method of test for external fire exposure to roofs.
- BS 476-7:1997 Method of test to determine the classification of the surface spread of flame of products.
- BS 476-22:1987 Methods for determination of the fire resistance of non-loadbearing elements of construction.
BS 5250:2002 Code of practice for control of condensation inbuildings.
BS 5950 Structural use of steelwork in building.
- BS 5950-2:2001 Specification for materials, fabrication and erection. Rolled and welded sections.
BS 8206 Lighting for buildings.
- BS 8206-2:2008 Code of practice for daylighting.
BS EN 10143:2006 Continuously hot-dip coated steel sheet and strip. Tolerances on dimensions and shape.
BS EN 10346:2009 Continuously hot-dip coated steel flat products. Technical delivery conditions.
BS EN 12056 Gravity drainage systems inside buildings.
- BS EN 12056-3:2000 Roof drainage, layout and calculation.
BS EN ISO 10211:2007 Thermal bridges in building construction. Heat flows and surface temperatures. Detailed calculations.
BS EN ISO 13788:2002 Hygrothermal performance of building components and building elements. Internal surface temperature to avoid critical surface humidity and interstitial condensation. Calculation methods.
MRCMA Technical paper 14. Guidance for the design of metal roofing and cladding to comply with Approved Document L2: 2001
TM 37: Design for improved solar shading. 2006

Performance

Substrate: Hot dipped galv. to BS EN 10143:2006

Table 04: Unfactored roof loads for Meta-Slate profiles (kN/m²)
Span Condition	Deflection Limit	Rafter Spacings
Span Condition	Deflection Limit	600	750	900	1000	1100	1100
		2.44	1.98	1.82	1.53	1.41	0.94
		1.85	1.56	1.33	1.18	0.99	0.67

Technical

Meta-Slate is manufactured from 0.7mm galvanised coil with a slate blue matt polyester paint finish to the outer surface and a grey epoxy based primer to the inside. The sheet is specially embossed with a regular slate pattern and finished to appear like natural slate. Other external colours and finishes are available by special order subject to quantity and coil availability.

Meta-Slate is ideal for use in environmentally sensitive locations where box profile sheeting may not be acceptable to local
authority planning departments.

Meta-Slate sheets are available up to 6 metres long and a full range of accessories is available including starter clips, joint pieces, ridge, hip and barge flashings, end closures, sealants and fixings. The use of joint plates combined with the regular slate pattern of the Meta-Slate sheet allows for economic use of the material thus providing a very cost effective system.

Table 01: Profile dimensions
Cover	300mm
Standard lengths	up to 6m
Weight:	6kg/m²

Table 02: Manufacturing tolerances
Cut to length L < 3m L > 3m	+/- 5mm +/- 10mm
Cover width	-0mm / +3mm
End square	-3mm / +3mm

Construction Details

Meta-Slate is available in standard lengths. Using a combination of these, together with the joining plate it is possible to clad any length and shape of roof. The joining of two lengths does not have to coincide with a truss/rafter as the joined lengths form an extremely rigid joint.

Meta-Slate roofing sheets can be fixed to either timber trusses, traditional rafters or metal purlins. The distance between each fixing point should not exceed 1000mm (800mm being optimum). Steadmans always recommend the use of roofing felt to act as a vapour barrier.

The lengths of Meta-Slate are easily cut using a standard power circular saw, jigsaw or hacksaw.

In order to achieve a 'tile hung' effect across the roof, the 'tile' pattern has to be staggered to its neighbour. For instance, in this example, length 2 has been cut at half a 'tile' pattern (marked A). The off-cut has been re-positioned at the other side of the roof to make up the 'tile hung' effect, and so on up to the depth of the roof as illustrated. For further information please contact our technical department.

Design Guiance

Steadfast locking system
Steadmans unique Lap Locking System. Once locked into position, this ingenious design provides a weather tight joint whilst also allowing repositioning.

No special fixings are required, but care must be taken not to compress the scroll. Each length is fixed at up to 1000mm centres and is covered by the length above it.

Every Meta-Slate sheet has a location marker beneath the locking system on the top edge of the sheet: the sheet is correctly positioned when the location marker becomes visible.

Supply and Site Handling

Meta-Slate sheets are available directly from Steadmans. Meta-Slate sheets are delivered to site in packs. Steel stillages are used at the bottom of the packs to provide protection and the ends of the packs are wrapped with plastic. Maximum pack weight is 2 tonne.

Meta-Slate sheets are usually delivered to site. Off loading is the responsibility of the customer. Delivery by self off-load vehicles can be arranged.

ONE ORDER
•
ONE DELIVERY
•
ONE INVOICE
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ONE NUMBER
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01697 478 277

Handling and storage
Meta-Slate sheets are delivered to site in packs. Steel stillages are used at the bottom of the packs to provide protection and the ends of the packs are wrapped with plastic. Maximum pack weight is 600kg.

The packs can be off-loaded directly to the roof, or to a storage area, which should be dry and well away from traffic. Packs may be stacked using suitable wooden bearers and packers. Bearers should be placed above each other.

Handle Meta-Slate sheets carefully to avoid marking weather sheets or liners. Lift sheets from the pack - do not drag them. Observe site health and safety procedures and the results of manual handling and other assessments.

Preparation
Before fixing any sheets check the squareness and accuracy of the framework. Determine the direction of the prevailing wind.
Check sheets for damage before fixing.

Sitework Diagram

Laying sequence

After the insulation board and roofing felt are in place, the Starter Clip lengths are fixed to the truss/rafter at the eaves.
The first length of Meta-Slate is then locked into the Starter Clip and secretly fixed onto the truss/rafter.
When the first length is completed, the second length is locked in to position utilising the unique Steadfast Locking System.
Adopting the Recommended Laying procedure as above, the roof is completed and capped with the Spring Ridge Clip.

An instructional fitting CD for the Meta-Slate Roofing Systems is available, contact Steadmans for more details.

Starter clip
The Starter Clip is designed to accept the first length of Meta-Slate at the eaves. The Meta-Slate is locked onto the Starter Clip and secretly fixed to truss/rafter.

Vapour Barrier
The use of a breathable moisture control layer is recommended.

Barge flashing
Once the roof is completed, a Barge Flashing is positioned to seal off the gable end of the building. The gaps created by the different angles of the Barge Flashing and the Meta-Slate are in-filled with expanding strip.

Apron flashing
A traditional solution to ensure a weather tight finish to a lean-to roof. The addition of a strip of lead flashing is recommended. The angle of the apron can be set to suit clients' specifications.

Joining plate (with weather sealant)
By sliding the Joining Plate under the end of an Meta-Slate length and joining another length to the plate as shown, an extremely rigid joint is achieved.

N.B. It is not necessary to make these joints at truss/rafter as the Joining Plate does not require fixing to the roof.

Starter Clip

Barge flashing

Apron flashing

< Joining plate >
Joining plate

Installation Guidance

Annual inspection
It is good practice to carry out annual inspection of the building
exterior and to carry out any remedial work identified during the inspection, see table 04.

Touch-up
Minor scuffing to the colour coating should not be treated. Deeper scratches which reach the substrate should be repaired with touch-up paint. The touch-up paint should only be applied to the original scratch using a fine paint brush. As touch-up paint will dry to a slightly different colour than the original coating the area which is touched up should be kept as small as possible.

Table 04 Checklist for annual inspection
Check for:	Remedial action:
Blocked gutters, which may cause overflow into the building.	Clean gutters and wash out any blockage.
Build-up of debris, which can retain water and cause corrosion.	Remove debris.
Dirt retention on areas not washed by rainwater: that affects the appearance of the building and, if left untreated, could cause the coating to breakdown.	Wash down with fresh water using a hose and soft bristle brush. Heavy deposits can be removed with a solution of water and household detergent or proprietary cleaner.
Mould growth, which is rare, but can affect the appearance of the building.	Wash down, then apply a cleansing solution: consult Steadmans Technical Department for guidance.
Local damage - breakthrough of the panel coating could result in corrosion of the substrate.	Assess the extent of the damage and either touch up (see opposite) or overpaint the affected area or replace damaged sheets.
Drilling swarf and fixing debris.	Remove debris.
Condition of fixings - faulty fixings can cause leaks or rust staining on the surface of the panels.	Replace faulty fixings and missing clips.
Corrosion of cut edges.	Cut or abrade edges back to clean bright metal and repaint: consult Steadmans Technical Department for guidance.

Associated Products

Gutters
Steadmans manufacture and supply a range of gutters to match the Meta-Slate profile.

Gutters are produced from a variety of materials including pre-galvanised steel (to BS EN 10143:2006) and pre-coated steel, either painted or PVC-coated on one or both sides; aluminium can be supplied to order. Complete gutter systems and accessories can be manufactured to specification, up to 10m long and 3mm thick: contact Steadmans' sales office for details of sizing.

A full range of Hunter Plastics rainwater systems is available to suit Meta-Slate: contact Steadmans for more information.

Flashings
Steadmans manufacture a range of flashings to match the profiles in matt polyester. Plastisol leathergrain, Nova, Scintilla, galvanised and PVDF finishes also available. Flashings can be supplied in lengths up to 6m in traditional profiles, or can be shaped to meet special customer requirements.

Sealants
Steadmans supply a range of NFRC Class A butyl sealants, profile foam fillers and expanding foams to enable profiles to be sealed to other building components, so avoiding thermal bridging and air leakage.

Meta-SlatePlus is a roofing sheet that has the appearance of natural slate but embodies the advantages of a modern lightweight but strong building material. Meta-SlatePlus is manufactured from 0.7mm galvanised coil with a slate blue matt polyester paint finish to the outer surface and a grey epoxy based primer to the inside. The sheet is specially embossed with a regular slate pattern and finished to appear like natural slate. Other external colours and finishes are available by special order subject to quantity and coil availability. Meta-SlatePlus is ideal for use in environmentally sensitive locations where box profile sheeting may not be acceptable to local authority planning departments. Meta-SlatePlus is extremely easy to fit and boasts a beautifully simple secret fix joint system. Meta-SlatePlus roofing sheets are available in lengths up to 6m.

The AS35 insulated panel consists of two coated steel profiles bonded to a core of PIR insulation. The metal sheets are made from either Z275 galvanised steel or AZ150 aluminium-zinc coated steel to BS EN 10346:2009. The top profile is 0.5mm thick, and the internal liner 0.4mm thick, and are both covered by a choice of one of several organic coatings. Panels are available in lengths of 1.8m to 12m and in thicknesses of 40, 60, 70, 80, 90, 105, 115, 120 and 137mm.

Meta-SlatePlus is designed to provide a strong, rigid slate effect roof with good thermal performance down to a 10° pitch. The system includes a comprehensive range of clips, jointing pieces, flashings, end closures, sealants and coated steel or plastic gutters and downpipes.

The Meta-SlatePlus system offers rapid coverage and swift completion of a weatherproof building envelope to give a high performance building. To download a pdf of the Meta-SlatePlus overview brochure, click here.

Performance, design & sitework
Performance data, design guidance, and sitework instructions for the Meta-SlatePlus slate effect roofing sheet is contained in the ‘Meta-Slate Roofing Systems’ technical brochure. To download a pdf of the Meta-Slate brochure, click here. An instructional fitting CD is also available from our sales department.

Performance data, design guidance, design details and sitework instructions for the AS35 panel is contained in the ‘AS35 Insulated Roof & Wall Panels’ technical brochure To download a pdf of the AS35 brochure, click here.

Fixing Meta-Slate roofing sheet over an AS35 insulated roofing panel
Once the AS35 has been securely fixed to the roof substructure in accordance with the Certificate holder’s instructions, the Meta-Slate roof sheets can be fixed in place.

The installation of the Meta-Slate roof sheets over the AS35 panels is very similar to the installation over rafter/purlins. The roof sheets are fixed every third raised section of the AS35 panel using 5.5mm by 25mm self-drilling screws. The screws are fixed through the overlap between panels so that the screw is driven through two thicknesses of the metal top sheet (fixed at a maximum of one per metre of panel length). The frequency of fixing can be increased around the edges of the installation or where special detailing is required.

Note: the projects shown here are examples of roofs fitted with the Meta-Slate roofing sheet.

Thermaslate