CI SfB (4-) Nn2

ONDULINE Classic sheets

The attractive durable lightweight

corrugated sheet roofing system
Design and installation manual
Complementary leaflet to the Onduline
BBA
BRITISH
BOARD OF
AGREMENT instructional film available online
CERTIFICATE NO. 87 / 1823

www.onduline.co.uk
 Onduline fixing guide:
This guide provides comprehensive design and installation guidance, you
can either select & click on the specific information you require from the
index below or view this guide and instructional video in full.

Contents:
01 Introduction 11 Ridge mono pitch roof
Onduline sheet specification Using Onduline verge piece
Identifying top surface of sheet Ridge verge abutment
02 Roof design Using Onduline ridge piece
Roof structure 12 Wall cladding rainscreen
Roof types and terminology Cladding options
Recommended tool kit 13 Valley detail
03 Roof construction Valley support structure / lining
Roof support options Marking sheet to valley
Support to sheet Cutting and positioning sheet
Sheet laps Valley saddle detail
Fixings to sheet 14 Hip detail
Sheet coverage Hip support structure
04 Preparation Fitting sheet to hip
Setting the roof out Laying ridge pieces to hips
Fixing purlins or decking Hip ridge abutment
Insulation and underlays Trimming hip ends
05 Fixing skills 15 Onduline roof window
Marking out sheets Fixing roof window
Cutting with handsaw 16 Onduline roof ventilators
Cutting with power saw Fixing roof ventilators
Cutting with tinsnips 17 End wall abutments
Cutting up length of sheet Fixing end wall abutment
06 Onduline fixing types Cover flashing
Plastic capped nails 18 Side wall abutment
Safetop nails / screws Fixing end wall abutment
Universal drill screw fixing Cover flashing
07 Fixing sheets 19 Curved roof application
Sheet side and end laps Support structure
Corrugation end laps Fixing sheets to curve
Corrugation side lap Sheet laps on curved roof
Sheet selection 20 Onduline Plastics
Sheets laid in broken bond Sheet selection
08 Fixing details: Eaves detail
Eaves detail. Sheet fixings
Eaves / verge detail 21 General design notes
Eaves tray option Onduline design notes
Ventilator comb 22 Roof oversheeting system
Corrugation filler Warm roofs
09 Verge detail Cold roofs
Nailed verge Ondutile tile underlay system
Lapped verge 23 General design notes
Onduline verge pieces Onduline
10 Ridge duo pitched roof
Ridge purlin positioning
Onduline ridge piece fixing
Ridge trimmed laps option
Ridge finial
 Onduline Classic

Corrugated bituminous sheet

roofing and cladding system
A tradition of quality
The Onduline Group is the worlds largest producer
of bituminous corrugated roofing products, selling
to over 120 countries worldwide.

Onduline classic sheet specification (nominal )

Sheet size: 2.000 x 0.950 m
Corrugation size: 95 x 38 mm
Thickness: 3 mm (nominal)
Lightweight: 6.4kg per sheet (nominal)
BBA Product Certification
Easy to handle, cut, shape and fix
15 year weather proofing guarantee subject Red
to terms and conditions
Excellent colour retention properties Brown
Withstands windspeeds of up to
120mph (192kph).
Green
Lightweight, only 6.4 kg per sheet Black
High thermal and sound insulation
Does not rust, or contain Asbestos
ISO 9001:2008 Quality Management Standard
ISO 14001: 2004 Environmental Management

Identifying top surface of sheet

Take care to fix Onduline sheets the correct way up,
the underside is easily identified by its dimpled rough
surface finish, whilst the top of the sheet has a
smoother textured finish
Warning: Check that your sheet and accessories are
genuine Onduline products. Failure to do so can result
in lower quality roof performance and invalidate the
Onduline roofing system guarantee. Upper sheet surface Lower sheet surface
 Roof design:
Roof structure Roof types and terminology
It really is worth taking the time to first Duo-pitch roof:
check your roof and carefully set out the
design for the support structure on your
project.
It will save you time and money!
New build project: Hipped roof: Mono-pitch
Just follow the information in this leaflet to create roof:
a durable low maintenance roof.
Existing roofs: Valley:
Survey your roof structure as this will allow you to Ridge:
decide if it requires maintenance, upgrading or Hip: Side wall
strengthening prior to fixing the Onduline sheets.
Verge: abutment:
Make note of the roof construction normally built
using purlins or boarded roof deck laid onto a Barge
timber portal or trussed rafter roof structure. board:
Warning: Check that existing purlins are fixed at
centres suitable for fixing Onduline sheets onto; as
many existing roofs do not offer sufficient sup-
port and failure to increase the support structure
can result in sheet deformation and a significant Fascia board:
shortening of the roofs service life. Roof decking:
Purlins / battens:
End wall abutment: Eaves:

Roof framing & design:

Recommended tool kit
Rafter or trussed roof Portal framed roof
construction: construction 6
5
supporting purlins:
7
4
8 9

1
2 3

11
10

Conventional trussed roofs:

Roof design is based on triangulated frames which
can be in the form of traditional framed structures
or constructed from trussed roof frames. 1 Hammer: 7 Course bladed hand saw:
2 Tin snips: 8 Protective gloves:
Portal framed roof structures: 3 9 Protective glasses:
Timber frame structures often use a portal frame Roofers knife:
construction which supports purlins to which the 4 Tape measure: 10 Electric rotary or skill saw:
Spray lubricating oil: 11 Protective hard hat:
roof covering material is affixed. 5
6 Straight edge:

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 Onduline
Introduction
Fixing Onduline sheets is a simple process just follow the simple
three step instructions set out in the tables below:

Roof support and fixing specification

Step 1: First measure the slope of your roof: To do this simple use a protractor or
1 inclinometer or alternatively calculate the roof slope using the roof slope
gradient.
Step 2: Select one of the three fixing options set out below that matches the slope
2 of your roof either: a: b: or c:

Step 3: Then just follow the fixing instructions described below the appropriate
3 fixing option; a: b: or c: They detail the correct support required below
the sheets, corrugation end and side laps and finally the sheet fixings.

a: b: c:
15o degrees or greater 10 to 15o degrees 10 to 5o degrees
Support to sheets

61cm 45cm Roof deck

Purlins should be fixed at Purlins should be fixed at A fully supporting decked roof
maximum centres of 61 cm. maximum centres of 45 cm. should be laid.
At the eaves allow for a 50cm At the eaves allow for a 50cm At the eaves allow for a 50cm
sheet overhang when positioning sheet overhang when positioning sheet overhang when positioning
the first purlin from the eaves. the first purlin from the eaves. the first purlin from the eaves.
 a:
15o degrees or greater
b:
10 to 15o degrees
c:
10 to 5o degrees
Sheet laps
Sheet end lap Sheet end lap Sheet end lap
17 cm 20 cm 30 cm

1 Corrugation 1 Corrugation 2 Corrugation

side lap side lap side lap
Lay the sheets with: Lay the sheets with: Lay the sheets with:
17cm sheet end lap 20cm sheet end lap 30cm sheet end lap
Single corrugation side lap Single corrugation side lap Double corrugation side lap

Sheet fixings

Nail every corrugation along of Nail every corrugation along of Nail every corrugation along of
the eaves, either side of the the eaves, either side of the the eaves, either side of the
vertical laps and every other vertical laps and every other vertical laps and every other
corrugation on the intermediate corrugation on the intermediate corrugation on the intermediate
purlins in a offset pattern. purlins in a offset pattern. purlins in a offset pattern.

Sheet coverage
Sheet size: 2.000 x 0.950 m Sheet size: 2.000 x 0.950 m Sheet size: 2.000 x 0.950 m
Corrugation: 95 x 38 mm Corrugation: 95 x 38 mm Corrugation: 95 x 38 mm
Fixings per sheet: 20 Fixings per sheet: 25 Fixings per sheet: 20

Sheet coverage: 1.56 m2 Sheet coverage: 1.54 m2 Sheet coverage: 1.29 m2

Sheet cover length: 1,830 m Sheet cover length: 1,800 m Sheet cover length: 1,700 m
17cm sheet end lap 20cm sheet end lap 30cm sheet end lap
Sheet cover width: 0.855 m Sheet cover width: 0.855 m Sheet cover width: 0.760 m
One corrugation side lap One corrugation side lap Two corrugation side lap

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 Preparation: 56
91

7 8
01
1

1
Setting the roof out 2
3
Fix sheets at the opposite end of the roof from the prevailing 4
winds. Then commence every other sheet course with a half
sheet forming a broken bond sheet layout to avoid a 4 ply
sheet thickness at sheet corners.

Fixing purlins or decking

Purlin size Fixing Purlins Fixing decking

Purlins must be of sufficient size to Take care to set the purlins out Decking should be laid in a
give support between the rafters. to the correct centres and then broken bond pattern fixed to a
Consult the table on page 19 for either nail or screw them to the minimum of three purlins in
guidance on the size of purlins trusses or rafters. accordance with the relevant
required. B.S. and Codes of Practice.

Fixing to existing deck Fixing Decking or Purlins Fixing Purlins to thin decks
Check the thickness of the deck. On thin decks, additional roof Then using a string line screw
You will need at least a 20 mm deck can be overlaid; or through the deck into the purlins
board to avoid the risk of the alternatively fix purlins set to the from inside the building; securing
fixings penetrating the interior of correct centres screwed first at the purlins onto the roof ready to
the building. the verges externally. accept the Onduline sheets.

Insulation and underlay membranes

Insulation upgrade Onduline underlays Laying Ondutiss membranes

The thermal performance of your The Ondutiss roofing and vapour Follow the Ondutiss product fixing
building can be upgraded by permeable roof underlay range is instructions, this requires 10 cm
laying insulation boards between designed for use below Onduline roll end laps and fixing to the
the purlins, having first laid an sheets. Select the membrane deck with 10 mm large headed
Ondutiss membrane. that matches your project needs. clout nails at 150 mm centres.

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 Fixing skills:
Onduline is designed to be simple to both handle and fix
requiring a minimum of trade skills and equipment, just
take the time to familiarise yourself with these basic skills
and use the recommended tools and success is assured.

Fixing Skills - Cutting sheet

Marking out the sheet Cutting with handsaw Cutting sheet width
Carefully measure the size of the Use a coarse bladed handsaw to Support the sheet cut ends and
material required and mark out cut Onduline sheets. Apply spray cut the sheet taking time to
the line to be cut onto the sheet lubricating oil onto the saw to clean and lubricate the blade as
surface. avoid the saw teeth from binding required.
with bitumen.

Cutting using power tool Cutting using power tool Cutting using tinsnips
Support the sheet either side of Always wear safety equipment First mark out the sheet or
the line to be cut taking care to and consult the manufacturers Onduline accessory. Cut with
allow the safe operation of instructions for safe operation an oiled pair of tinsnips to form
power rotary circular or skill saw. when using power tools. detailed shapes in the onduline
material.

WARNING
.
Working on roofs at heights can
be hazardous. Always work from a
Cutting up corrugation. Cutting up corrugation. secure ladder or platform and use
First mark out the line of the Next fold back the sheet along the appropriate safety equipment.
cut in the base of the sheet the cut / scored line to separate Guidance can be found in Health
corrugation. Use a roofers knife the cut sections of the sheet.
and Safety Guide HSG33 working
to score the Onduline.
on roofs.

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 Onduline fixings:
Plastic headed
Monobloc nails

Safetop nails (+ Screw option)

The Onduline range of fixings allows the sheets to be easily
fixed to a wide range of roof structures.
Select the fixing matching your requirements from either
Plastic headed nails, or Safetop nail (screw option) or the
Onduline universal drill screw.

Onduline sheet fixings Universal screws

Plastics capped Monobloc nails Plastic capped Monobloc nails

Onduline plastic headed nails Fix by striking the preformed
are a cost effective solution for Monobloc head with the
fixing the majority of roof types. hammer through the top of the
Fixing options Refer to a: b: or corrugation. Note: You do not
c: fixing specifications have to pre-drill the sheet.

Safetop nail fixing Safetop screw fixing Safetop washer cap.

The safetop assemble features a Alternatively, you can replace The safetop assemble is finished
heavier duty nail, use by nailing the standard nail supplied with a by clipping the cap onto the
through the washer into the top proprietary screw; using the cap washer assemble. Note: If the
of the sheet corrugation. and washer, ideal for fixing the cap has been displaced use
sheets to thin decked roofs. sealant adhesive to secure.

Universal screws Universal screws. Universal screws.

Onduline universal screws can A chuck drill bit holder is used The screw is suitable for drilling into
be used on both timber and to retain a Phillips HEX insert bit a wide range of standard steel
steel purlins. They feature a required to drill the universal screw pulins, we recommend you check
screw and integral weathering into the purlins. its suitability prior to starting work
washer. Note: Bit size 1/4 25mm PH No2. by undertaking test fixings.

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 Fixing Details:
To guarantee a professional roof follow the guidance in this section to create a
well-founded and durable roof on your building.

Sheet side and end laps

17cm
20cm
30cm 1 corrugation lap
Sheet end lap Sheet end lap Corrugation side lap
Mark out the correct sheet end The cover width being either: Form a single corrugation side lap
laps on the sheet matching your a: 150 degrees or greater: 17 cm. on options a and b:
roof slope as specified in the b: 100 to 150 degrees: 20 cm. a: 150 degrees or greater.
a, b. or c roof specifications set c: 50 to 100 degree: 30 cm. b: 100 to 150 degree.
out above.

2 corrugation lap
Broken bond pattern
Corrugation side lap Sheet selection
When setting a roof out start al-
Form a double corrugation side Warning: Always check the sheets
ternate courses with a half sheet
lap for option c: are the genuine Onduline Classic
to form a broken bond pattern
c: 50 to 100 degree sheets. Beware of imitations!
thus avoiding a 4 ply sheet
thickness at edges of sheets.

Eaves fixing details

5cm
5cm

Fixing sheet at Eaves Eaves and Verge

Form a 5 cm sheet drip edge at Ensure the sheets are positioned
the eaves. Remember to reduce square to the line of the eaves
the distance to the first purlin up and verge, first nailing the sheet
Onduline eaves detail from the eaves to allow for the edges (allowing for laps) to keep
Allow a nominal 5 cm overhang sheet overhang at the eaves. sheets square to the eaves line.
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Eaves fixing options

Eaves tray Ventilator comb Corrugation filler

The versatile Onduline eaves Fixed to the eaves and ridge it Used to seal the corrugations
tray can be used to reduce the stops ingress of birds and large at eaves and ridge from ingress
sheet overhang at the eaves. insects into the roof space, whilst of sand and dust into the roof
It is also a component part of maintaining a ventilation airflow space. Alternative ventilation
the Ondutile and Oversheeting into the roof space. provision should be made.
systems.

Verge fixing options

Nailed verge option Lapped verge option

Fix a verge barge board within First align and fix the verge barge
the last corrugation then fold board with the purlins, then
Onduline verge detail down the corrugation edge and overlap the sheet corrugation by
For a superior weathering detail nail using galvanised clout nails nominally 5mm secure by nailing
at 15cm centres. the sheet at every purlin.

Verge piece fixing Verge piece fixing

First align and fix the verge barge Secure the verge units by nailing
board with the purlins, Then through the verge and top of the
Onduline verge pieces position preformed Onduline Onduline sheet corrugation on
For a superior weathering detail verge units with a 20cm end lap the roof and through the vertical
(ensure the end lap is secured). upstands into the barge board.

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Ridge duo pitched roof detail

Ridge purlin positioning Ridge purlin fixing

Use a ridge piece to determine Screw or nail the purlin into place
and mark the position of the onto the roof trusses.
Ridge detail purlin required to accept the We recommend that purlins are
Providing assured weathering ridge fixings. Its position is variable also positioned to support the
and ventilation into the roof. dependant on the roof slope. sheet ends at the ridge.

Ridge piece fixing Lapping ridge piece Fixing ridge piece

Lay the Onduline preformed Ridges are fixed by aligning the Mark a fixing line on the roof and
ridge units into position they are preformed grooves (nominal end secure the ridges by nailing every
sufficiantly flexiable to allow the lap of 220mm), the ridges are other corrugation ensuring the
ridge to be formed to match laid from the opposite end of the grooved ridge piece laps are
variable roof slope. roof from the prevailing wind. secured either side of the lap.

Option. Trimmed laps Option. Trimmed laps Option. Trimmed laps

A superior ridge line finish can be To do this use a roofers knife to Trim the ridge pieces on a bench
achieved by trimming the lower trim the edges of the end of the then install on the roof.
ridge piece to be lapped, this ridge piece to be overlaid. Always use a deep straight to cut
provides a smoother line to the against as a safeguard against
ridge pieces once fixed. the knife slipping.

Option. Trimmed laps Finial ridge closure Fixing Ridge finial closure
Using the trimmed edge option Terminate the ridge end by The finial is then simple fixed to
when fixed in position the ridge marking out and cutting a the verge barge boards and
end laps are less evident and a treated timber finial to match the finished to match the decorative
neater ridge line is established. ridge profile. finish applied to the verge barge
boards.

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Mono pitched ridge using verge or ridge pieces

Mono ridge structure Onduline eaves filler

Mark out and fix a ridge facia Position and lay Onduline
board, incorporating a high level corrugation filler onto the
Mono ridge verge detail ventilation channel into the roof Onduline sheets to seal the
Using Onduline verge pieces and space providing a continuous corrugations from wind driven
corrugation filler. 10mm air gap into the building. rain and snow at the eaves.

Fixing verge pieces. Completing the fixing Overlay Verge abutment

Next lay the verge pieces over Complete the fixing by nailing At verge and hip abutments the
the mono ridge abutment, rear of the verge trim onto the ridge section must always be laid
compresing the corrugation filler ridge fascia board at 15cm onto the verge / hip section to
by fixing into each corrugation. centres. Press the safetop caps weather the roof.
onto the washer bases.

Onduline ridge piece Onduline ridge ventilation

Alternatively Onduline ridge The corrugations provide a high
pieces can be used to seal a level ventilation into the roof
Mono pitch ridge detail mono ridge abutment after first space. The ridge is nailed to
Using Onduline ridge pieces to fixing an additional purlin to every other corrugation and ei-
weather ridge detail. accept the ridge fixings. ther side of the ridge end laps.

Wall cladding & rain-screen applications

Wall cladding fixing specification
The sheets can either be laid on a studded
Plywood frame (1) with a vapour permeable
membrane laid to the wall prior to fixing the
treated timber studding with high and low
ventilation provided to the sheet. Alternatively
the sheets can be laid on a timber studded
frame (2) with the purlins set at 61 cm centres.
1 2 However, if insulated boards are placed
between the purlins the spacing can be
opened to 90cm. Onduline sheets should not
be laid within 1 metre of ground level.

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Valley detail

Valley support structure Valley lining options

The support structure to the The valley base can then be
valley is constructed by first fixing overlaid with metal or suitable
trimming battens to the purlins, roofing membrane weathering
Onduline valley detail and lining with valley boards to membrane to form a durable
Minimum 7.5 cm valley drainage provide a 7.5cm gutter depth. valley lining.

Fixing GRP valley lining Onduline valley lining Fixing valley lining
Alternatively pre-formed GRP Another option is to use The Onduline units are secured
valley liners are laid between pre-formed Onduline valley to the purlins trimming battens by
the purlin trimming battens and lining pieces, these laid on nailings at 20cm centres up the
secured by nailing. underlay can fully supporting plywood valley line of the gutter.
be dressed over the upstands. boards positioned.

Marking sheet to valley Cutting sheet Positioning sheet

Position the Onduline sheets up Remove the sheets from the The sheets are then positioned
the line of the valley and mark roof supporting either side of the back on the roof, aligned square
out the cut line, allowing for a required cut line, then use a to the line of the roof sheets
minimum of 4cm sheet drip edge mechanical saw to cut the providing the minum of 4cm drip
into the valley gutter. sheets as required. edge into gutter.

Fixing sheet to valley Fixing sheet to valley Valley saddle detail.

The sheets are fixed in place The fixings to the roof sheets can a saddle weathering should be
allowing for the correct sheet then be applied. used to seal the valley lining at
side and end laps. The fixings are the ridge abutment, allowing the
secured up the line of the purlin ridge pieces to be laid onto the
trimming battens. roof.
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Hip detail

Hip support structure Fixing the sheets to hip

Position the Onduline sheets up Reposition sheets back onto the
the line of the hip and mark the roof, square to the line of the roof
line to be cut allowing a 5cm provide the correct side and end
Hip detail sheet drip edge at the eaves. laps. A hip board will assist in this
Assured weathing detail Remove from the roof and cut. and also support the ridge units.

Aligning ridge pieces Fixing ridges pieces

Fixing ridges to hip
Position and carefully mark out The ridges are fixed by
The ridges are fixed to the lines
a line to which the ridge pieces aligning the ridge piece pre-
marked out on the sheets. Fixing
can be aligned up the hips. Start formed grooves (nominal end
through the ridge top of the
fixing the ridges from the eaves lap of 220mm), in accordance
sheet corrugation into each pur-
up the line of the hip to the ridge. with the fixing specification.
lin up the roof hip.

Hip to ridge joint Hip ridge abutment Trim hip ends

The ridges are cut into the line of On exposed sites the lapped sec- The hip ridge pieces can be
the ridge board. The ridge units tion between the hip and ridge finished at the eaves by trimming
can then be overlaid and fixed pieces should be sealed with the ends to the line of the eaves
to form the hip abutment. Onduline sealant adhesive. using a saw or tinsnips.

Onduline roof window

Onduline roof window Fixing Onduline window

The front apron laps onto the Complete by cutting and
lower sheet, this might require an lapping the sheets onto the back
Onduline roof window extra short purlin to accept the and side window weathering
For illumination and ventilation. front apron fixings. aprons and then fix to purlins.

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Onduline roof ventilators

Basic verge detail Onduline verge pieces

Roof ventilators are available in The ventilators are fixed between
two sizes to provide increased the purlins. The apron is lapped
ventilation and should be used over the lower sheet, with the
Onduline roof ventilators mid span on roof slope / lengths integral side and back gutter
For assured roof ventilation. greater than 11m. aprons being lapped by next.

End wall abutment

Onduline apron fixing Apron cover flashing

Use Onduline pre-formed apron To allow for differential
flashing piece to seal end wall movement between the wall
abutments. Lay the upstand and the roof sections always use
Onduline apron pieces against the wall and fix the front a seperate wall cover flashing
For a superior weathering detail apron at each corrugation. dressed into a prepared joint.

Side wall abutment detail

Side wall abutment Upstand to wall
Overlay at least one Onduline To allow for differential
corrugations with a proprietary movement between the wall
preformed abutment flashing and the roof sections always use
dressed up the wall and fix a seperate wall cover flashing
through the top of corrugation. dressed into a prepared joint.

Side wall abutment

Metal or preformed proprietary
side wall abutments; or
Onduband self-adhesive flashing
tape are used to seal side wall
abutments providing a minimum
of 7.5 cm upturn against the wall
and dressed over at least one full
Onduline corrugation.
Complete with a separate wall
cover flashing.

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Curved roof detail
Dome Onduline fixing to curved roof:
Onduline sheets can be formed to curved roofs. First check
5 degrees
0
5 degrees
0
the sheet can be formed to the required radius. The support
purlins at the ridge should be set at 42.5 cm centres as the
pitch becomes shallow, the ridge must always be capped
with a full Onduline sheet width. The purlin centres on the side
cheeks of the roof can be widened to 61 cm. Fix Onduline
ventilation units to the roof sides as required.
Full sheet used to cap ridgePlate line
Note: On buildings with high internal humidity levels close
Onduline boarding; or roof decking must be used at the ridge and
Onduline Classic sheets Purlin centres
Ondutiss underlay membrane can be used with enhanced
ventilation provision.
Purlins
Overlap 30cm Fixing sheets on curved roof:
The sheets must always be laid with 2 corrugation side laps
Important - For buildings with high
humidity levels, see designers note. and 30 cm sheet end laps on the curved roof.

Sheet laid to roof curve Marking the sheet Fixing sheet at eaves
The sheets are laid with 2 Mark out the sheet nail points on In this instance we are using
corrugation side laps and 30 cm every corrugation along of the Onduline screw fixings securing
sheet end laps on the curved eaves, either side of the vertical the eaves line first. Secure the
roof, position the sheet square to laps, and every other corrugation sheet edges first then work to the
the eaves and verge line. on the intermediate purlins. centre (allowing for laps).

Forming sheet to curve Applying sheet fixings Secure remaining fixings

Use a timber batten to compress Maintaining pressure on the The remaining fixings can then
the sheet to the required roof batten apply fixings to secure be secured forming the sheet to
curvature then mark out fixing sheet in place, securing the sides roof curve.
points on the sheet. of the sheet square to the verge
line (allow for sheet laps).

30cm
end lap

1 2 side lap
Curved roof mono ridge Sheet laps to curved roof Curved roof specifications
Onduline ridge and corrugation Always provide a double The inherent flexibility of
filler are used to seal mono ridge corrugation sheet side lap and Onduline sheets make them ideal
abutments, fix the sheet at every 30 cm sheet end lap on curved for curved roof projects. Our
sheet corrugation and provide roof slopes to allow for possible technical sales department can
high level roof ventilation. deformation of the sheet laps. assist you with your project.

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 Onduline Plastics:
Onduline Plastic sheets share the same Onduline profile and sheet
dimensions and are accordingly simple to fix to your roof, providing top
class light transmission provision into your building.
Sheets are available in both crystal clear and opaque finishes and are
available in PVC and Polycarbonate materials.
Check out the website for full details on the full Onduline Plastics range.

Fixing plastic roof illumination sheets

Clear; or Opaque sheet? Sheet side laps

We offer two roof sheet options; To avoid sheet discolouration
opaque which tends to be easier under U.V. heat exposure always
Onduline plastics to handle and clear which is lap the Onduline sheet onto the
For a superior weathering and more brittle to handle but offers plastic sheets on the sheet side
light tranmission properties. glass clear light transmission. laps.

Drip edge to eaves Marking fixing points Pre-drilling fixing points

Allow for a 5 cm drip edge at the Mark out the fixing points onto Pre-drill the fixing holes with a
eaves. To protect against U.V. the plastic sheet in accordance 5.5mm drill to allow for thermal
heat exposure discolouration to with the Onduline sheet fixing sheet movement around the
the plastic sheets, first paint any instructions. fixings in service.
dark roof support elements white.

WARNING
Fixings selection Applying fixings . Only genuine Onduline Plastics
Use the same Onduline fixing Carefully screw or nail the fixings are recognised under the terms of
matching the Onduline roof into position. Note: it is the Onduline product guarantee.
section, in this case we are using important the fixings are not The Onduline plastics division will
Onduline universal screws which overtightened to allow for be pleased to assist with the roof
are generally easier to apply to thermal movement in the plastic illumination PVC, GRP and
plastic sheets. sheets. polycarbonate product range.

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 Design notes:
Please check the website for additional
product information, product and design
data sheets.

General design notes

Timber Purlin roof design: Maintenance:
Timber purlins should be of sufficient size to To ensure a long life the roof should be
provide support the Onduline 95 x 38 mm sheet cleared of leaves and debris and gutters
corrugation spanning charactisitics and cleaned regularly. Any branches in contact
associated roof loads between supports. with the roof surface should be removed.
Note: Fire classification limitations:
The table below gives suggested minimum Onduline sheets are not classified to External
timber purlin sections for roof pitches over 150 S.AA fire rating as required in UK Building
including allowances for normal snow loadings. Regulations for some classes of structure. In
these instances they must be fixed on a fully
Span Typical timber section sizes for supporting roof deck and the sheets coated
treated softwood purlins (on with a proprietary AA surface paint
roof pitches above 150) treatment applied in strict accordance with
the paint manufacturers instructions.
(m) (mm) Condensation:
0.450 38 x 25 Onduline is highly resistant to the build-up of
0.610 50 x 50 condensation. However, any single thickness
2.4 38 x 75 roofing material is at risk of condensation
3.0 38 x 100 formation. It can also be the case that during
3.6 38 x 125 the winter months water vapour present
4.2 44 x 150 within the building can freeze to the
4.5 50 x 150 underside of the sheets; this ice then melts as
4.8 50 x 160 the roof warms in the morning forming water
5.4 63 x 175 droplets which can drip off the sheets.
Note: Consult the Condensation & Ventilation
6.0 63 x 200
Data sheet for further information.
6.6 75 x 200
Ventilation:
Note: A range of Onduline ventilation accessories
This table is prepared as a guide only in are available to assist in the provision of high
consultation with TRADA the British Timber and low level ventilation which will reduce the
Research and Development Association. risk of condensation formation.
However, design needs can vary according to
roof layout and building regulations. Professional
advice should always be sought for specific roof
design applications.

Snow loadings:
We recommend on buildings situated in exposed
locations or situated in elevated regions subject
to periodic high snow loading that Onduline
sheets are fixed onto a roof deck. And the use
of both enhanced vapour control measures and
ventilation provision is incorporated.
 Onduline roof renovation system
The light weight of the Onduline roofing system makes it ideal for Oversheeting existing
failing and deteriorated fibre cement or steel pitched roof coverings.
The system can be used in either cold or warm roof configurations. For detailed design
specifications consult the Onduline roof renovation Oversheeting fixing guide.

Cold roof over sheeting

Roof preparation:
A thorough inspection of the existing roof
structure should be undertaken and any
deterioration should be rectified, the
Fascia board
structure checked as to its suitability for
Eaves tray
Oversheeting procedures. A review of the
original roof design should also be made
Onduline sheets laid
to check that sufficient ventilation and
on purlins fixed to the
insulation is provided and if any necessary
support battens.
alterations are required in the roof refur-
Onduline support batten fixed
bishment to upgrade the roof design and
to existing roof structure.
performance.
Existing deteriorated
corrugated roof covering.
Existing purlin roof structure
Cold roof over sheeting specification
Determine the fixings required to secure the support
battens to the existing roof support structure as re-
quired in conformity to British Standards & Codes of Onduline support Support purlins are
Practice. Note: The fixings must offer sufficient battens are fixed to then fixed to roof
resistance to wind uplift specialist fixings suppliers existing roof structure structure
should be consulted for advice. The support battens Note: The Onduline roof renovation leaf-
are then overlaid with the appropriate support let should be consulted for detailed fixing
structure to the Onduline sheets in accordance with specifications, technical advice should be
the Onduline roof renovation fixing guide leaflet. sought to detail your specific project.

Warm roof over sheeting The Ondutile system

Warm roof over sheeting specification The Ondutile under tile roofing system
Insulation is recommended and should always be Only Onduline Classic grade sheets are
used on steel roofs to avoid the risk of heat transfer suitable for use with the market leading
into the building. To reduce the risk of condensation, Ondutile tile and slate underlay roofing
it is essential that insulation products are laid in system. This unique system allows tiles to
accordance with the manufacturers instructions. be safely used below the manufacturers
They should include an effective water vapour minimum recommended roof pitch and
barrier laid beneath the insulation. If high levels of benefits from system BBA certification.
moisture is present within the building, mechanical Note: The Ondutile leaflet should be
vapour extraction should also be provided. consulted for detailed fixing specifications.
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Other Instructional leaflets
Onduvilla tiles
Onduvilla tile strips are produced with a unique three
tone colour in an attractive bold roll tile profile. This
recreates the warm natural colours that are normally

Note: The information in this brochure is correct at the time publishing, Onduline reserve the right to change specifications at any time without prior notice. Production team: Tony & Kev Knell, Claire Hayzer, Ian McDonald, Bob & Richard Gibson, Hollie Walker, Video: FACT Liverpool - VERSION 01.01- 2016
only associated with expensive and heavy clay roof
finishes. Onduvilla is produced in an easy to handle
and fix tile strip format, making them the ideal roof
covering for a wide range timber framed garden and
commercial buildings.

Bardoline shingles
Bardoline tile strip shingles enhance both the style,
durability and roof performance of housing, domes-
tic and commercial building projects. Its lightweight,
ease of use and fixing allied to its proven versatility
make Bardoline the natural choice for a wide range of
building projects.

OnduLINE MINI 18 SHEETS

Onduline Mini 18 sheets are designed with a low profile
corrugation which compliments perfectly the scale of
sheds, summer houses, workshops and garages. Making
Mini 18 the ideal Do it Once upgrade to your garden
and timber frame buildings.
Mini profile sheets are also the only approved sheet for
use with the Ondutile low line tile underlay system.

Maintenance
To ensure a long service life for your shingles the roof should be
cleaned regularly of leaves and debris, as leaf mould can reduce the
service life of the product. Also check that tree and shrub overhanging
branches are not into contact with the surface of the roof; as wind
generated movement can cause surface damage.

Terms and Conditions

Although the colouring process in the manufacture of the Onduline
products are long lasting, as with similar natural roofing materials
it is subject to the effects of weathering over its lifetime. The colour
can also differ between production batches.

Copyright 2016 All rights reserved. No part of this publication may be reproduced, distributed, or
transmitted in any form or by any means, including photocopying, recording, or other electronic or
mechanical methods, without the prior written permission of Onduline Building Products Ltd.

www.onduline.co.uk
BBA Onduline Building Products Ltd
BRITISH
BOARD OF
AGREMENT
CERTIFICATE NO. 87 / 1823
Eardley House, 182-184 Campden Hill Road,
Kensington, London, W8 7AS
Tel: 020 7727 0533
Fax: 020 7792 1390
www.onduline.co.uk E-mail: enquiries@onduline.net
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