# Forum Home Renovation Structural Renovation  Weatherboard Overlap

## dno

<o>Just purchased some square edge weatherboards from my local hardware and I am a bit confused with the size 170mm. I have read that overlap needs to be at least 30mm which leaves me with only 140mm coverage.<o></o> The original boards on my house are much wider and when overlapped have coverage of 160mm.<o></o> Can the overlap be reduced to 20mm giving me a 150mm with no problems or is 140mm a normal coverage.<o></o> Any advice would be greatly appreciated.<o></o></o>

----------


## Claw Hama

I'm not a builder but if they were mine I think I could sleep ok at night with 20 mm coverage. Then if they are painted and most of the joint is covered it should seal well enough.

----------


## TermiMonster

140mm is pretty standard in my experience.
TM

----------


## Bloss

140mm cover is common, but a 20mm overlap would be OK too especially if you have foil insulation behind the boards as I would recommend. 
Many older narrower molded profile weatherboards had just a 10mm overlap, but the precision joint and rounded shape added water resistance.

----------


## dno

Thanks for the feedback. I think I might go with 150mm coverage. I have also found that the new boards are thicker and dont sit as flush as the originals. May be a shrinkage thing.

----------


## peter_sm

My weatherboards have 150mm coverage, and appear to have 20-25mm overlap.

----------

