Onduline Onduline
Guides
Roof Installation
1. SETTING OUT
Please adhere to the maximum spacing of purlins according to roof pitch charts in this document. Distance between purlins must be the same. Sheets are fixed directly on purlins.
2. CUTTING
First mark out the sheet then cut with an oiled coarse-toothed handsaw, or preferably a power saw.
3. SHEET LAYOUT

Start fixing sheets at the opposite end of the roof from prevailing winds. Cut a sheet in half vertically, and use to lay sheet courses in a broken bond pattern.

4. FIXING
Use Onduline recommended nails or screws. Check you have the correct sheet side lap and sheet end lap. Use a string line to keep fixings aligned. Always fix on top of corrugation.
5. FIXING ORDER
See larger drawing in this document about fixing order and fixing details
6. EAVES DETAILS
The maximum sheet overhang at the eaves is 7cm. Reduce the distance of the first purlin from the facia accordingly.
7. RIDGE UNIT FIXING
Fit ridge board and support purlin. Fix second purlin, its position being dictated by the roof pitch. The sheet /ridge can then be fixed.
8. RIDGE FIXING UNIT
Start fixing the ridge at the opposite end of the roof from prevailing winds, and form a minimum of 12.5cm overlap. Use a string line to align. See detailed relevant drawing in this document.
9. HIP DETAIL
Fix hips before ridges. Lay support board and trimming purlins. Fix ridge units to trimming purlins, cut and dress units and overlay with ridges.
10. VERGE FIXING
Fasten barge board level with the top of finished Onduline roof. The Onduline verge units are then overlaid and fixed into position. Use Onduline verge or Onduline ridge as verge.
11. VERGE FIXING (ALTERNATIVE)
Alternatively, fix barge board level with the underside of the Onduline corrugation and overhang corrugation. Fold down and fix in position.
12. SIDE WALL ABUTMENT
Form side wall flashing to Onduline roof, using Onduline Reparo flashing tape or similar, and fix separate cover flashing to the wall.
13. END WALL ABUTMENT
Use Onduline pre-formed apron flashing to seal end wall abutments. Use separate cover flashing to the wall to allow for movement.

14. ONDULINE TILE EFFECT
Cutting Onduline sheets into 50cm lengths and fixing with a 20cm overlap easily creates a pleasing tile effect shadow line.
 

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