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Insulation when siding possible?

I would like to re-side home in the next year, I currently live in Minneapols, Mn and my walls are quite cold in the winter time. I have some type of brown fiber board under my cedar shakes and very little insulation in the walls, I only assume due to wood peckers and fixing the holes from time to time when they appear.

If and when I re-side my home can I take all of that fiber board off and insulate the walls from the outside, put up plywood sheets and wrap it for warmer walls in the winter? Can I use regular insulation, or does it have to be something special or can I not do that at all?

Basically I would like to insulate my walls, can I and how to do it from the outside if possible?

Re: Insulation when siding possible?

Yes you can.
- From your city building dept you can find the minimum R value for exterior wall insulation required.
- Buy enough insulation to meet this R value and start by removing the old exterior, to the framing.
- BTW, now you can inspect your framing, make any electrical or plumbing changes necessary, and start filling the wall cavities. Don't stuff them so tight, just fill to required R value.
- If you want to use plywood, consider the added thickness around windows and doors. Follow required nailing schedule, specified by bldg dept. Be careful around pipes, add metal protectors if needed.
- Wrap and side. Pay attention and install correctly at the bottom of the walls and at the top of the walls, to make the house water tight.

Re: Insulation when siding possible?

I second yes, but. If you use regular kraft paper backed batts, fold the paper wings over the side of the insulation so the insulation material pushes the wings against the studs. Push the batts all the way to the interior wall surface, the fiberglass will fluff back out over time. You can pull the insulation away from the paper at the top to staple the wings so it doesn't sag over time, but you only need one or two staples per side.

There are other alternatives such as using unfaced batts but you should get a vapor barrier primer and paint the inside wall surface. Do not paint the studs though. If you plan on painting the interior of the house, you can use the vapor barrier primer on the inside surface of the exterior walls instead.

Now for a word of caution. Taking down the fiberboard, aka blackboard, is OK, but you should find the the corners use plywood instead. The plywood in the corners is to keep the house from racking. Before you remove any of this plywood to put in insulation, be sure you have finished some other cavities and have replaced the blackboard with plywood. If you don't so that, you could end up with some severe structural damage.

Be sure to use plywood that is the same thickness as the blackboard you take down, that way everything fits back together as it should.

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