I am planning on replacing the roof on my 50-year-old bungalow soon and decided it would be a good time to put in some new insulation in the attic as well. The insulation there is the old loose grey kind. I suppose that I'll have to pull it all out first so that there's a place to put the new insulation between the boards. Some of it has gotten wet in places anyway and probably isn't doing much good.

a) what is the easiest way to remove the old insulation? do I have to pick it all up by hand and bag it?

The second problem is that there's no ventilation in parts of the attic. The second floor of the house is broken up so that there are 5 separate sections of attic that aren't connected. The crawlspace along the top ridge possibly has some ventilation through the gables (at least it looks like this from the outside, but I have no way of getting inside). The other 4 are on the corners of the building (the living area forms a T in the center of the upstairs) and, although I can see daylight breaking through cracks in places, there is no formal ventilation.
I've read about the importance of ventilation, but it seems weird that the house has gone this long without any.

b)Is there any damage I should look for? How important is it for me to add ventilation now, and what exactly is needed?

 

First of all you will need to treat each of the 5 spaces as a separate "attic"
Each one should have about 1 sq in of free vent area for every sq ft of attic space.
Perferably try to divide this area evenly between the low sections and high sections of each attic.
Standard square roof vents work well for smaller attics, while the wind powered spinning turbines work well for larger areas (over 500 sq ft)
Both types are easy to install and can be done without going into the attic.
Be sure to add intake venting in the soffit or the exhaust vents are basically useless.

BTW, the lack of venting could have been the cause for the damp/wet insulation in your attic.