Jere writes from Bellingham, Washington: "I live in Bellingham, WA 98229. We have an uninsulated crawl space under the house. What R factor insulation should we apply?"

Answer: The recommendation depends on how big your rafters are. If you have 2x6 rafters, I recommend R-21. If you have 2x8, I recommend R-25. You will want faced insulation with the paper facing up towards the first floor. You can use insulation hangers to hold it up. They can usually be found at any place that has insulation. Also, if you have a dirt floor you will want to cover it with a 4-6 mil polyethylene sheet. There is a useful guide and convenient dealer search at www.itseasytoinsulate.com. Just click on EASY WEEKEND PROJECTS and you will see the Homeowner's Guide to Insulating in the bottom left-hand corner.