Peeling Paint On Redwood Siding: What To Do?

I've seen it happen at countless houses, and now it's happened to me... my paint is peeling (again).  I have a Minneapolis home that was built in 1939 with redwood siding, and I can't get the paint to stay on.  I've tried almost everything and nothing has worked so far.  The photo below shows what my siding looks like today.



I'm not a paint expert, but I think I've figured out why my paint keeps peeling.

I first painted my house during the summer of 2004, and the paint began to crack the very next year.  By 2007 it was peeling so much that I had to re-paint.  I had a good friend help me with the project, and we felt like we pulled out all the stops and spared no expense to make sure the paint wouldn't peel again.  This project consumed a huge portion of our summer - we spent so much time working on my house that summer that the 'Google Streets' view of my house even caught us in action.



Here's what we did during the summer of 2007:

• Scraped with carbide paint scrapers.  We scraped the existing paint all the way down to the wood in many areas.
• Sanded a good portion of the siding, especially at the front.
• Washed the siding with Trisodium Phosphate (TSP).
• Tested the siding in many areas with a moisture meter to verify that the wood was bone-dry before proceeding.
•  Primed the siding with Peel Bond, an expensive primer that has the consistency of runny glue.  This stuff was supposed to be the greatest primer ever... maybe it is, but it still wasn't enough.
• Painted with Hirschfield's Platinum Exterior paint.  My friend assured me that it's top-of-the-line stuff.

So here I am, not even three years later, and the paint is cracking and peeling all over again.  It's worst at the east side, but it's still peeling everywhere else.  Some rooms in my house have vapor barriers on the inside walls and some don't, but it doesn't make a bit of difference to the paint.  It peels off the same.  Both the original paint is peeling, and the new paint as well.


So what now?


My suspicion is that with so many layers of paint, the house walls have basically become 'sealed'.  Instead of the siding being able to 'breath', where moisture can escape between the laps of the siding, the laps have been completely sealed shut with layer after layer of paint.  In the areas where there is still a gap between the layers of siding, the paint still looks perfect - not even a hint of a crack or a flake.



I've been told that the fix for this is to install siding shims - small wedges that would ensure a small air gap at every lap.  I would need to install these every sixteen inches at every piece of siding.  This should fix the peeling paint, but it might also allow bugs to use my siding as their home.

Bad times.

If you're having problems similar to mine, check for an air space between the laps of siding.  Let me know what you find.


Reuben Saltzman, Structure Tech Home Inspections - Email - Minneapolis Home Inspector