Rick writes from Roodhouse, Illinois: "I am removing wood siding and replacing the windows of my home. The home has partial insulation so I am planning on removing what's there and replacing with batt insulation and then possibly rigid insulation before siding. A couple questions: 1. Can I batt from the outside and if so, do I use faced? 2. Can I use rigid insulation as sheathing as well and just affix siding to the studs; is this done? 3. I have heard of people extending the 2x4s with another 2-inch piece all around; ever heard of this?"

Thanks, Rick. Good questions.

1) Yes, you can batt from the outside as long as you can properly install the insulation into the wall cavity without compressing it. Also, make sure the entire cavity is completely sealed with insulation. If your local codes call for a vapor barrier you should use Kraft-faced insulation.

2) Yes, this is a very common method. Fasten the PINK (what else?!) FOAMULAR sheathing directly to the studs. The vinyl siding must also be attached to the studs. Make sure you are using a fastener long enough to penetrate the studs through the foam insulation.

3) Yes, that technique is called "furring out the studs." People do this to increase the depth of the wall cavity so they can install insulation with a higher R-Value. For example, if someone furred out a 2 x 4 wall 2 inches, they can now use an R 19 or 6-1/4" insulation rather than an R-13 or 3-1/2" batt.

If you aren't aware of them, there are also siding products that can add insulating value. The Owens Corning product is called the Polar Wall Plus! Insulated Siding Panel. It is available to the trade through the company's Norandex Distribution Centers.