1 the installation guide for hardie board which is a brand of cement board siding recommends using caulking to fill nail holes.
Filling nail holes in cedar siding.
Filling nail holes nail holes in interior walls can generally be filled with shrink free spackling by overfilling the hole slightly then sanding smooth once it s dry.
Roughen the area you want to patch with 80 grit sandpaper for a better bond.
To patch holes and depressions in siding of any kind follow these steps.
Fill the siding holes with wood filler.
Choosing the best wood filler for your project.
Use a putty knife to force the filler inside the hole making sure to fill in the hole and to completely cover the opening.
Some are suitable for filling voids such as divots holes or gouges in.
Holes in wood trim are best filled with wood filler.
Epoxy putty is a commonly recommended wood filler for use in repairing woodpecker damage.
I would suggest famowood as it shrinks the least and have a good selection of colours.
Repairing minor defects in cedar siding step 1 use a putty knife to apply exterior wood putty to smaller cracks or holes in siding.
Wood filler can be used for small holes dents etc.
Clean the hole or depression you plan to fill.
The best filler for your siding is a two part epoxy product that cures to a rock hard consistency.
When i ve installed it i used a high quality exterior paintable calking after smoothing the edge of the holes.
Once the caulk is dry you can touch up the paint.
Fill the area with patching compound.
Clear paintable caulking can be used on cracks gaps.
1 scrape all loose paint from around the area to be repaired using a paint scraper or putty.
Work the putty down into the holes and smear the putty over the top and edges of the defect.
Nail holes in exterior surfaces just as with cracks or gaps can be dealt with using a good caulking.