How to Install a Hardy Plank Soffit

HardieSoffit panels are a fiber-cement composite soffit panel and offer a distinct look, compared to aluminum and vinyl soffit panels. The fiber-cement material offers a variety of cutting methods, but you should employ the cutting methods that produce the least amount of silica dust, as silica dust can cause lung irritation and could cause the potentially deadly lung condition known as silicosis. Therefore, it is best for you to avoid cutting the HardieSoffit panels with a power saw and always cut the material outdoors.

Things You'll Need

• Two sawhorses
• 4-foot by 8-foot piece of plywood
• HardieSoffit panel
• Tape measure
• Carpenter's pencil
• 24-inch framing square
• Utility knife
• 2-inch wood screws
• Screw gun with a No. 2 Phillips screw adapter
• Latex caulk
• Drop-in caulk gun
• Clean rags

Instructions

1. Set up the two sawhorses parallel to each other, roughly 5 feet apart and place the 4-foot by 8-foot piece of plywood across the two sawhorses to create a stable worktable.

2. Place a piece of HardieSoffit on top of your newly formed worktable.

3. Pull the tape measure along the length of the piece of HardieSoffit and mark the cut length on the surface of the HardieSoffit with the carpenter's pencil.

4. Set the 24-inch framing square against the side of the HardieSoffit panel and align one side of the framing square blade with the length mark you placed on the face of the HardieSoffit.

5. Rest the carpenter's pencil against the side of the framing square and drag the pencil along the edge of the framing square to make a cut line on the surface of the soffit panel. Do not remove the framing square from the cut location. The pencil line is for reference in case the framing square is bumped.

6. Apply pressure on the framing square with one hand and run the utility knife along the side of the framing score resting on the cut line with the other hand. You need to make multiple passes with the utility knife to score the HardieSoffit panel at least 50 percent of the way through the thickness of the soffit panel.

7. Slide the score line on the HardieSoffit to the end of the worktable, apply pressure down on the length of the soffit panel on the worktable with one hand and press firmly on the length of the panel overhanging the worktable with the other hand to snap the panel to length.

8. Mark the location of each roof joist on the face of the HardieSoffit panel and extend each mark with the framing square. These will be reference marks for when the HardieSoffit is in place.

9. Place a pencil mark 1/2 an inch in from either longitudinal side of the HardieSoffit, on each roof joist line you drew on the face of the HardieSoffit panel.

10. Hold the cut HardieSoffit panel in the soffit and run a 2-inch wood screw into each 3/8-inch mark you placed on the face of the soffit panel with the screw gun and No. 2 Phillips screw adapter.

11. Place an additional screw on each marked reference line for the roof joist, roughly in the center of the width of the HardieSoffit panel.

12. Cut and mark another piece of HardieSoffit panel and place it into the unprotected soffit.

13. Slide the length of HardieSoffit toward the installed length of soffit panel, leaving a 1/8-inch gap between the ends of the two panels and screw the HardieSoffit to the roof joists as described earlier.

14. Cut open the nozzle of the latex caulk tube with the drop-in caulk gun, after all the HardieSoffit panels have been installed, caulk each seam between the HardieSoffit panels.

15. Run a bead of caulk around the entire perimeter of the HardieSoffit panels and smooth the latex caulk with your finger.

16. Caulk the head of each 2-inch wood screw holding the HardieSoffit panel and smooth them with your finger.

17. Clean your finger with warm water and a clean rag to remove the latex caulking.

18. Allow the latex caulking to cure before you paint the HardieSoffit panel.

References

• "James Hardie: HardieSoffit Panels"