How to fasten weatherboard panels?

[damianpc]

Hi all. 

I am about to clad a wall of a pergola with timber weatherboard. I've built the stud wall but am wondering the accepted practice for nailing/screwing to the frame. 

I've seen some people nail at the bottom edge of the panel, into the top edge of the underlying panel. I've also seen people nail in the top edge so the bottom of the overlapping panel sits on top of the nail and hides it. Ideally this is the method I would choose, so as to hide nails/holes etc.  

Is there any reason why you'd do one over the other?

Thanks

Damian

[MitchellMc]

Hi @damianpc,

You should follow the installation guide for your chosen product to comply with the manufacturer’s requirements and maintain your warranty.

Both fixing methods have their merits. Nailing through the bottom edge of the board into the top edge of the board below provides a strong hold but leaves the nails exposed. Concealed fixing, where nails are placed near the top edge and covered by the overlapping board, creates a cleaner look but may offer slightly less resistance to movement over time.

If you’re using James Hardie Linea, their installation guide allows for both methods, so concealed fixing is fine if you prefer a neater finish.

Please let me know if you have any questions.

Mitchell

[damianpc]

Thanks Mitchell. 

It is just using straight up timber weatherboard.

Would there be a maximum thickness where you wouldn't use the concealed method?

Thanks,

Damian

[MitchellMc]

For solid timber weatherboards @damianpc, the concealed fixing method is generally used for thinner boards—often up to around 12–16mm thick—where the nails can securely hold the board without risk of splitting or inadequate fastening. If the boards are much thicker, say 18mm or more, face fixing may be preferred to ensure a strong connection to the frame, as concealed nails might not provide enough holding power.

It’s also worth considering timber movement. Thicker boards tend to expand and contract more with changes in moisture, so face fixing can help minimise the risk of cupping or warping over time. Checking the recommendations from the supplier would be a good idea to ensure the best approach.

Mitchell