SLE Cladding Limited

Timber fixing schedule

Schedule of components
Component options - subject to design requirements
Onduline ridge piece	900mm length
Onduline verge piece	1100mm length
(125mm end lap used for ridge & verge pieces
Ventilator strip	1000mm length
Onduline eaves filler	846mm length
Eaves tray	1275mm length (150mm end lap
Insulation material	to suit thermal design requirements

Installation notes

These installation notes are for general guidance only in fixing Onduline material. For special applications or variations in roof form, please contact Onduline's technical department for assistance.

Caution

Covering existing fragile corrugated roofs is a specialist operation. All work should be carried out with due regard to all Health & Safety regulations: this is of particular importance when dealing with fibre-cement materials possibly containing asbestos. Under no circumstances should blue and brown asbestos be oversheeted and on any roof containing old asbestos , consult your Environmental Health Officer for guidance and follow relevant site handling requirements. It is advisable not to clean corrugated fibre-cement sheets. Treat them with a dilute PVA adhesive coating to consolidate the internal and external surfaces prior to fixing. Finally lay Ondutiss roofing membrane onto main support battens to seal roof. Building regulations should be adhered to and in some instances planning approval may be required.

Preparation

A thorough inspection of the existing roof structure should be undertaken, any deterioration of the existing roof should be rectified and the structure checked as to its suitability for oversheeting procedures. A revue of the original roof design should be made to check that sufficient ventilation and insulation is provided, and if necessary alterations incorporated in the Onduline Oversheeting System refurbishment.

Fire resistance.

All statutory requirements should be adhered to in accordance with relevant British Standards and Code of Practice. Consult Onduline's technical department if specific project information is required.

Fixing procedure

Fixing the main support battens

Select the correct section of timber to suit existing sheet corrugation size in accordance with timber schedule, and fix from eaves to ridge through the existing roof covering in accordance with fixing schedule.

NOTE:

Allowance should be made for additional space required for provision of insulation.
Fragile roofs will require pre-drilling.
All battens must be treated.
If asbestos is expected in the roof, overlay main support battens with Ondutiss membrane.

Fixing Onduline support battens

Overlay and fix the main battens with the Onduline support battens, verge to verge, at 450 or 600mm centres in accordance with the Onduline timber fixing schedule.

Note. Eaves tray and ridge components require additional support battens.

Fixing Onduline sheets

Care should be taken rto ensure that the fixing penetrate the batten centrally

Insulation option

Onduliss vapour check membrane is laid up the roof from verge to verge over the main support battens with 100mm side and end laps. The Ondutiss is overlaid with the Onduline support battens. The insulation is laid between the support battens. The Onduline sheet can then be fixed.

Note. Ventilation must be provided below the Onduline sheet.

Main Batten

Fixed from eaves to ridge at 600mm centres or on exposed sites at 450mm centres. Batten size (mm) in accordance with the following table.
Std. 6" asbestos-cement & fibre-cement	75 x 50 or 50 x 50
Std. 3" asbestos-cement or fibre-cement	50 x 38 or 50 x 50
Profiled galvanised or plastic coated steel or iron	50 x 38 or 50 x 50


Onduline support battens
Fixed verge to verge
Roof pitches over 15 deg.	600mm centres
Roof pitches 10 to 15 deg.	450mm centres
Batten size	25 x 38 or 50 x 50mm

Mechanical fixing schedule

Fixing main battens to existing roof purlins

Fixing to existing timber purlins

Annular ring shank nails

125 x 3.35mm or 75 x 3.35mm

Wood screws

125 x 10g

Fixing to existing steel purlins

Galvanised J type bolts, self tapping or self drilling screws. Size and type to suit existing purlin type

Fixing Onduline support batten to main batten

Annular ring shank nails 65 x 6.65mm

Fixing Onduline sheets to support batten

Onduline PE nails or Onduline Safe Top heavy duty nails.

Fixing Onduline sheets to steel batten

Stelfix drill screws.


Self Tap	Self Drill	Annular	J-type	Stelfix