We are remodeling a 150-200 year old farmhouse that has 10 inch wood planks on the ceiling in the dining room. Dirt and dust falls down from in between the cracks. Is there anything we can do to fill these cracks that will be permanent and not crack (like caulking probably would)? We are wanting to keep the ceiling, but may have to sheetrock over it if we can't come up with a good solution. We don't want dirt and dust falling down into our plates while eating dinner!