How to build a fibre cement fence?

[ifresh]

Hi,

 

My neighbour and I are about to construct a 3m dividing fence between our duplexes. He plans on using Duratex exterior base sheet 3000 x 1200 x 7.5mm to clad his side (and we would likely use something similar).

Posts are 2.5mm galvanised steel that with 1000mm footing with 2000mm spacing.

He has created a design but I have checked the installation guides for duratex and hardieflex and they both say 600mm distances for vertical studs. If I could have some direction on what needs to be adjusted to support the fc sheets properly.

[JacobZ]

Hi @ifresh,

While Duratex is suitable for outdoor use, this is not its typical application, so it is unlikely James Hardie would offer any form of warranty on this type of installation if their sheeting were to fail. In saying this, it is fairly common to see fences made with fibre cement sheeting even though it is not their typical use. If you were to use Duratex for this purpose, you would want to follow its installation guide as closely as possible, with some slight modifications.

In your case, you could do this by ensuring the horizontal rails are spaced no more than 600mm apart. For example, this would mean the 3m tall posts need 5 rails as opposed to the 4 that are shown. 

You would also need to add vertical blocking between the rails wherever sheets butt into each other. This will ensure the perimeter of the sheet is adequately fixed and will line up perfectly with the adjacent sheet.

By making these couple of modifications, you are essentially following the same installation criteria as with vertical stud framing, it is just turned on its side.

It's also important that screws are spaced no more than 200mm apart across the full width of the sheet and around the perimeter.

Let me know what you think and if you have further questions, please don't hesitate to ask.

Jacob

[ifresh]

Thanks Jacob I appreciate the guidance.

Would you also be able to recommend the right screws to go through the 7.5mm fc sheets and 2.5mm steel posts? And a suitable timber to run along the top to cap the fence? 

[JacobZ]

Hi @ifresh,

James Hardie recommends using these James Hardie 41mm Phillips Head Collated Screws for steel connections. They are collated for use with a collated screw gun, but they can also be pulled off the strip and driven in with an impact driver or drill.

If you didn't need 1000 screws, these Buildex 10-16 x 45mm Climacoat Metal Wing Tek Screws are very similar.

You could cap it with a suitably wide decking board that is oiled to protect from the elements or, if you wanted to paint it, a piece of dressed treated pine, such as this 92 x 18mm LOSP H3 Treated Pine or 138 x 18mm LOSP H3 Treated Pine depending on the eventual thickness of the fence.

Let me know what you think.

Jacob