Not sure how long oatmeal will last, but you can use saw dust and wood shavings instead of oatmeal. If it's the rust texture you are working at, you can also cover the piece with concrete patch. Mix the wood shavings into the patch and use a stick to make the patch surface rough.Anyone know how long the oatmeal paint survives? Sounds risky with critters lurking in the attic or even just mold.