Metal Tiles and Metal Roofs
Hip & Gable Roof - Eaves Detail
| Soffit Width (mm) | 300 | 450 | 600 | 750 | 900 |
| Dimension 'A' (mm) | 295 | 445 | 595 | 745 | 895 |
Note:
- A 10mm soffit clearance has been allowed for:
- Soffit bearers fixed to LEFT hand side of rafter (viewed from outside).
- Based on minimum Purlin/Roof batten thickness of 45mm
Gable End Detail
| Soffit Width (mm) | 300 | 450 | 600 |
| Dimension 'A' (mm) | 295 | 445 | 595 |
In heavy snowfall areas, brackets and snow straps must be fixed at 450mm centres. In high wind areas it is advisable to fix the brackets at 600-700mm centres maximum. Refer to note 4 below for gable end timber sizes
Drop Heights (Dimension C in mm) for Roof Pitch and Soffit Width
| Roof Pitch (degrees) | Soffit Width 300mm | Soffit Width 450mm | Soffit Width 600mm | Soffit Width 750mm | Soffit Width 900mm | Dimension B (mm) Toe Cut, Gable Roof Only |
| 10 | 60 | 90 | 120 | 150 | 180 | 105 |
| 12.5 | 72 | 107 | 142 | 177 | 212 | 105 |
| 15 | 83 | 123 | 163 | 204 | 244 | 105 |
| 17.5 | 98 | 145 | 192 | 240 | 287 | 105 |
| 20 | 113 | 167 | 222 | 277 | 331 | 105 |
| 22.5 | 129 | 191 | 253 | 315 | 377 | 105 |
| 25 | 145 | 215 | 284 | 354 | 424 | 105 |
| 30 | 170 | 255 | 340 | 425 | 510 | 105 |
| 35 | 206 | 309 | 412 | 515 | 618 | 105 |
| 40 | 247 | 370 | 494 | 617 | 741 | 105 |
| 45 | 280 | 420 | 560 | 700 | 840 | 105 |
Notes for Installers
- To ensure birds cannot enter the roof space, there should be no gap between the bottom purlin and the back face of the gutter after the system has been installed.
- The 147 small panel fascia system is suitable for use with metal tiles and roofs with sloping soffits up to 22.5° roof pitch.
- Over 25° roof pitch, a kickout may be required on all gable ends.
- As an alternative to note 3, for gable end roofs, outriggers to be from finished timber sizes 70mm x 45mm i.e. gable end truss drop 70mm, avoiding kickouts up to 40° roof pitch.
- NOTE: Soffit bearers are required on all hip corners and should be cut back 20mm to all free movement of the spouting.
- Zincalume coated gutters should have a minimum fall of at least 1:500 and should not have permanent ponding.
- Where loose fill insulation is used, the soffit must be blocked off at the top plate to prevent the insulation coming into contact with the metal fascia. Check with your nearest distributor for further details.
Concrete Tile Roofs
Hip & Gable Roof - Eaves Detail
| Soffit Width mm | 300 | 450 | 600 |
| Dimonsion 'A' mm | 295 | 445 | 595 |
Note:
- A 10mm soffit clearance has been allowed for:
- Soffit bearers fixed to LEFT hand side of rafter (viewed from outside).
- Based on minimum Purlin/Roof batten thickness of 47mm.
Gable End Detail
| Soffit Width mm | 300 | 450 | 600 |
| Dimension 'A' mm | 295 | 445 | 595 |
Drop Heights (Dimension C in mm) for Roof Pitch and Soffit Width
| Roof Pitch (degree) | Soffit Width 300mm | Soffit Width 450mm | Soffit Width 600mm | Soffit Width 750mm | Soffit Width 900mm | Dimonsion 'B' (mm) Toe Cut Gable Roof Only |
| 17.5 | 32 | 119 | 166 | 2013 | 261 | 85 |
| 20 | 84 | 141 | 195 | 250 | 305 | 88 |
| 22.5 | 101 | 163 | 226 | 288 | 350 | 91 |
| 25 | 117 | 187 | 257 | 327 | 397 | 95 |
| 30 | 150 | 237 | 323 | 410 | 497 | 100 |
| 35 | 187 | 292 | 397 | 502 | 607 | 112 |
| 40 | 227 | 353 | 479 | 605 | 731 | 124 |
| 45 | 275 | 425 | 757 | 725 | 875 | 135 |
Notes for Installers
- To ensure birds cannot enter the roof space, there should be no gap between the bottom purlin and the back face of the gutter after the system has been installed.
- The 147 small panel fascia is not suitable on concrete tile roofs with sloping soffits.
- For concrete tile gable end roofs, outriggers to be from finished timber sizes 70mm x 45mm i.e. gable end truss drop 70mm.
- Over 25° roof pitch, a kickout is required on all gable ends.
- NOTE: Sofit bearers are required on all hip corners and should be cut back 20mm to allow free movement of the spouting.
- Zincalume coated gutters should have a minimum fall of at least 1:500 and should not have permanent ponding.
- Where loose fill insulation is used, the soffit must be blocked off at the top plate to prevent the insulation coming into contact with the metal fascia. Check with your nearest distributor for further details.
Dimond coated steel fascia systems are available in 147mm and 185mm high panel, roll formed in 0.55mm BMT zincalume with a prepainted finish only. Unpainted zincalume product, copper, stainless steel and aluminium are not available.
The outer edge of the soffit lining is retained at the bottom of the fascia in a rolled groove.
Design Instructions
- Shingle Roof - When installing Fascia rafter brackets over ply on top of the rafters the set out dimensions are
Dimensions "B" | |
147 Fascia Panel | 145 |
185 Fascia Panel | 175 |
Using these dimensions allows for a 10-12mm gap between the fascia and underside of the ply
- Brackets are nailed or screw fixed to the soffit bearer or rafters when sloping soffits are used.
- The recommended set out heights must be maintained to avoid birds and vermin entering the roof space.
- Steel products should not come into contact with concrete and must avoid dissimilar metal contact.
- When selecting the gutter to use with the fascia system it is important to:
i) Consider the catchment area draining into the gutter (called flow load) to ensure the capacity of the gutter (called flow capacity) has not been exceeded.
ii) Ensure the gutter with bracket can physically fit onto the fascia vertical face, laid to a fall of a minimum 1:500 and give an acceptable appearance. If not, select another smaller gutter size.
Construction Instructions
Selection of metal fascias needs to be made before the trusses are manufactured as the set out dimension may vary between the different systems available.
- Builders must ensure the timber soffit bearers are correctly set out using the published guidelines for the roof type being used prior to the fascia installation.
- Fascia brackets are nailed or screwed onto the soffit bearers to a level and true alignment using a string line.
- 6m maximum length of fascia are then fitted to the fascia brackets, cut back in length where necessary, and lengths joined together using normal roofing practice with silicone sealant and 4mm diameter rivets at 150mm maximum centres. Corner soakers are fitted over the fascias and rivetted on to cover corner joints.
- Metal fascia are specialised system that require specialised installers. Metal roofers do not normally install fascia. We do not recommend, support or approve DIY installations. Specialist companies throughout New Zealand install Dimond fascia. Contact Dimond for a list of installers in your area. Phone 0800 DIMOND (0800 346 663).
