Nails corroding on new fence - help! Topics ranging from metal fencing, wooden fencing and concrete fencing to name just a few. find answers and post your questions here

[3greens]

Hi,
Recently had a fence put up. After a few days, these stains started to appear around the nails.
The nails were sunk into the wood and filled with glue/sawdust .
The builder says galvanised nails were used so unsure of why there is corrosion. Any ideas from the forum and ways to fix this? The wood was good quality and came at a fairly large cost so this is a massive blow!

fence1.PNG (117.67 KiB) Viewed 2067 times

[stoneyboy]

Hi 3greens,
Unfortunately there’s a fair chance the nails were manufactured in China and their quality will be variable.
If your nails have been driven below the surface with a punch this may have cut through the galvanising exposing the steel beneath.
Your fence looks like it’s oak so any contact with steel will produce the staining which is appearing. You do need to determine the issue before corrective work is done but this will probably entail replacing the panels.
Regards S

[3greens]

Hi Stoneyboy,
Thanks for the quick reply. That makes a lot of sense - I hadn't considered the coating on the nails might have become damaged and that seems like a sensible conclusion. 2 things that strike me though:

If you look at the pattern of the stains, they appear to have a smudged appearance. Across the whole of the wall (which you can't see in the original photo), the stains seem to go off in different directions. This makes me think it might actually be the glue/sawdust mix which is causing the stain, or at least containing it.

Secondly, the wall is quite big. I've attached another photo to demonstrate. If the nails were damaged, do you still think it's likely that almost all were damaged in the same way? I'm an absolute novice so fully appreciate the answer might be yes!

The wood is called Iroko. I'm hoping it can be salvaged as having to replace all the panels would be a significant expense sadly!

Thanks,

3G

[stoneyboy]

Hi 3greens.
Suggest you pick one of the worst stained areas, dig out the filler and then pull out the nail to check it is galvanised. You should be able to check that the staining is, or is not, caused by the filler used.
I seem to recall that where Iroko is used externally and the wood does not have a protective stain, only marine grade stainless fixings should be used.
Regards S