Rusty nail fixings on exterior walls

Cause

Heads of fixings are not protected by putty where punched and stopped 

Repair

  • remove corrosion by brushing with a stiff bristle brush; prime sanded/brushed areas with a zinc-rich primer and a metal primer, punch and fill punch holes with putty or exterior grade flexible (polyester) filler; prime; paint with at least two coats of semi-gloss or high gloss acrylic paint 

Cause

Incorrect fixing type used for environmental conditions, cladding type or finish 

Repair

  • replace existing fixings with suitable fixings for the conditions: select hot-dip galvanised, stainless steel or silicone bronze as required

Cause

Rust was not cleaned off fixings before re-stopping/repainting

Repair

  • remove corrosion by brushing with a stiff bristle brush; prime sanded/brushed areas with a zinc-rich primer and a metal primer, punch and fill punch holes with putty or exterior grade flexible (polyester) filler; prime; paint with at least two coats of semi-gloss or high gloss acrylic paint 

Cause

Inadequate paint finish to provide protection

Repair

  • remove corrosion by brushing with a stiff bristle brush; prime sanded/brushed areas with a zinc-rich primer and a metal primer, punch and fill punch holes with putty or exterior grade flexible (polyester) filler; prime; paint with at least two coats of semi-gloss or high gloss acrylic paint 

Cause

Acidic leachate from cedar or H4-treated timber (containing copper-based preservatives)

Repair

  • remove corrosion by brushing with a stiff bristle brush; prime sanded/brushed areas with a zinc-rich primer and a metal primer, punch and fill punch holes with putty or exterior grade flexible (polyester) filler; prime; paint with at least two coats of semi-gloss or high gloss acrylic paint 

Cause

Corrosion protection of fixings (such as zinc) was damaged during installation

Repair

  • remove corrosion by brushing with a stiff bristle brush; prime sanded/brushed areas with a zinc-rich primer and a metal primer, punch and fill punch holes with putty or exterior grade flexible (polyester) filler; prime; paint with at least two coats of semi-gloss or high gloss acrylic paint