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proDuct informationissue no. 001 January 2016

ash & lacy building systems ltd

lonDon

gateway 3, Davis road

off cox lane, chessington

surrey Kt9 1tD

t 0208 391 9700

f 0208 391 9701

West bromWich

bromford lane

West bromwich

West midlands b70 7JJ

t 0121 525 1444

f 0121 525 3444

glasgoW

unit 4b, albion trading est

south street, Whiteinch

glasgow g14 0sY

t 0141 950 6040

f 0141 950 6080

eXeter

units 2&3 gloucester court

heathpark ind est, honiton

Devon eX14 1sJ

t 01404 549100

f 01404 549440

neath - port talbot

unit 4b, sirius Drive

rutherglen centre

baglan sa12 7br

t 01639 812569

f 01639 813133

cape toWn

29 atlantic Drive

bluewater estate

Kommetjie, cape town 7975

t +27+21+783 0114

m +27+83+215 1782

spacer systems

4dion.marsh@ashandlacy.com • www.ashandlacy.co.za • M +27+83+215 1782

refurbishment applications

refurbishment Ashgrid AG40 Safe-LocTM is an ideal component for the over-roofing or over-cladding of any building where the existing roofing or cladding has become unsightly, beyond repair or an improvement in the thermal performance is required

Ashgrid AG40 Safe-LocTM is installed over the in-situ roofing or cladding, providing a stable platform for the new weather sheet. This also creates a cavity between the new and the old where insulation can be inserted to increase the building’s thermal performance to current building regulations and reduce carbon emissions. This allows for a completely new weather sheet to be installed with minimal disturbance to operations within the building and improves the overall aesthetic.

The Ashgrid System is compatible with all forms of pierced andconcealed fix weather sheets available in South Africa and is specifically designed to evenly distribute the loads directly into the existing roof structure.

Ash & Lacy would always recommend that any new system should be fixed to structural members and not to an existing secondary system.

Brackets should be installed as per standard procedures, at a maximum of 1m centres and ensuring a bracket within 100mm of a spigot end. (Bracket centres may need to be reduced in areas of high wind suction or heavy snow loading). Comprehensive load span tables are available from Ash & Lacy South Africa.

Dependant on the condition of the existing roofing materials a vapour control layer and breather membrane may be required.

Care should always be taken when working with old or deteriorated materials, existing sheeting can be brittle and all precautions should be taken to ensure a safe working platform.

When installing Ashgrid Safe-LocTM spacer support system over existing asbestos it is advisable to pre-drill a clearance hole to prevent damage. Drilling should be carried out in conjunction with an H-Series asbestos vacuum which is available for purchase or daily hire from Ash & Lacy South Africa.

All works involving asbestos should be carried out in accordance with the South African Government Gazette Regulation No. 7276 Vol. 440 Pretoria 10 February 2002 No. 23108.

2

Refurbishment Applications 2

Asbestos 3

Over-roofing applications 4

Installation 5

Method One 5

Method Two 6

contents

spacer systems

6dion.marsh@ashandlacy.com • www.ashandlacy.co.za • M +27+83+215 1782Roof • Façade • Screen • Fabrication • SpaceR SySteMS • Fixings • Steel Frame5

spacer systems

Metal sheet over steel purlin with new pierced fix weather-sheet.

Asbestos-cement sheet over steel purlin with new pierced fix weather-sheet.

Composite sheet over steel purlin with new pierced fix weather-sheet.

Metal sheet over steel purlin with new concealed fix weather-sheet.

Asbestos-cement sheet over concrete purlin with new concealed fix weather-sheet.

Composite sheet over steel purlin with new concealed fix weather-sheet.

over-roofing applicationsasbestos

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asbestos

Professionals or contractors encountering asbestos roofs may feel confusion about how to handle asbestos-containing materials. Some may even avoid asbestos roofs altogether assuming they will equate to expensive asbestos-removal procedures and red tape. However, asbestos abatement (the process of removing or minimizing asbestos health hazards from a structure) can take many forms, including removal, enclosure or encapsulation and doesn’t need to be as daunting as it seems.

The average asbestos cement sheet contains no more than about 10% asbestos and the fibres are deeply encapsulated within a cement casing. The inherently strong natural bond between cement and asbestos fibres makes emission of fibres impossible without physical abrasive cutting, abrasive cleaning, impact damage, severe lichen encroachment or fire damage.

The first priority when deciding best practice on how to deal with an asbestos roof is to ascertain whether the material in its current condition is at risk of releasing asbestos fibres. Friable asbestos-containing-materials (ACMs)* are considered dangerous or at risk of releasing fibres whilst Non-friable ACMs** are considered safe and at no risk of releasing fibres.

There are further sub-categories of non-friable ACMs with asbestos-cement corrugated roof sheets falling into the lowest risk category. If there is still uncertainty of the materials condition an assessment of the material can be carried out by an authorised asbestos assessment consultant.

The vast majority of asbestos-cement roofs encountered in South Africa are in a non-friable condition and are at no risk of releasing asbestos fibres. Safer abatement methods such as enclosure are recommended in these cases. Demolition and removal carries a

higher risk of releasing fibres whilst disposal has severe environmental consequences.

The enclosure of the asbestos-cement roof sheets prevents any further risk of weathering or deterioration rendering the material inert and safe for the remainder of the life cycle of the building.

Asbestos-cement roofs should be considered fragile and when any roof work is performed, suitable roof ladders, duckboards or crawling boards should be utilised in accordance with regulation 12 of the General Safety Regulations published by Government notice R1031 of 30 May 1986. Good practice is to install a cargo net over the existing asbestos roof which is in turn secured around the perimeter. This sacrificial fall arrest system remains in-situ once the insulation and new outer roof covering has been installed.

Spacer systems are traditionally secured through the troughs of the asbestos sheets into the underlying purlin. This drilling process can be carried out in conjunction with an H-Series Asbestos vacuum which captures 100% of the dust produced.

These vacuums are fitted with an Ulpa Filter for 99.999% efficiency at 0.12 micron. They are ESD safe, meet HSG264 standards of surveying and are fully compliant with BS EN 60335-2-69.

*Friable ACM is any material that contains more than one percent asbestos by weight or area, depending on whether it is a bulk or sheet material and can be crumbled, pulverized, or reduced to powder by the pressure of an ordinary human hand.

**Non-friable ACM is any material that contains more than one percent asbestos, but cannot be pulverized under hand pressure.

Further information is available on request from Ash & Lacy South Africa.

spacer systems

8dion.marsh@ashandlacy.com • www.ashandlacy.co.za • M +27+83+215 1782Roof • Façade • Screen • Fabrication • SpaceR SySteMS • Fixings • Steel Frame7

spacer systems

With the advent of the SANS 10400XA energy efficiency legislation there is a requirement for deeper thermal cavities within roof assemblies and it has become increasingly important that careful consideration be given to the safety and security of the installers and the spacer support system, in particular during the construction phases.

A roofing system is at its greatest risk during the installation

stage when it is not restrained by the top sheeting and is subjected to loading from foot traffic, temporary loading and heavy sheet packs. This combined with drag forces from high winds tends to compound these problems further. With construction depths increasingly exceeding 200mm and with the ongoing need to improve installation efficiency and system performance, Ashgrid AG40 has been further enhanced to satisfy these increasingly demanding requirements.

1. Lay bar on roof deck and offer the small flange of the bracket to the small flange of the bar.

2. Tilt and rotate bracket backwards at desired fixing position.

3. Twist bracket and snap into position at 90° to bar.

Choice of installation methods to suit personal preference and site conditions

Method 1

installation

1. Offer the bracket to the bar at an angle from the non-spigot end.

4. Making certain there is a bracket within 100mm of a spigot end, install additional brackets to match the liner module up to 1m centres maximum. (Bracket centres may need to be reducedin areas of high wind suction or heavy snow loading).

2. Slide brackets along the bar to the desired fixing positions.

5. Engage the open end of the bar onto the Safe-Loc™ spigot and push firmly until the tab clicks into position. To release, simply depress the tab with a sharp object such as a screwdriver.

3. Snap each bracket upright to lock into position at 90° to the bar.

6. Continue as above for quick, safe and secure installation.

Brackets should be fixed to the substrate using two of the appropriate Ash & Lacy fixings for the application; also ensure the brackets are not twisted in the bar.

Brackets may be repositioned by reversing this action and sliding along the bar as in steps 1 & 2.

Method 2

construction depths up to and including 250mm

All spacer support systems will be exposed to in-line sway forces during their installation. To counter this, the stability of AG40 has been further enhanced through improvements in bracket design and the introduction of the Safe-Loc™ spigots. These designed-in features perform each and every time, providing peace of mind without reliance on extra, time

consuming bar-end fixings and anti-sway brackets. For cavity depths up to and including 250mm no additional sway control measures need to be employed on the new Ashgrid AG40.

For exceptional site loading conditions and for heights above 250mm advice on performance should be sought from the Ash & Lacy Technical Department.

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