There are several main advantages of basement insulation. These include: insulating the basement can keep the entire home warmer making significantly lower, it keeps the basement much dryer, and it provides a comfortable living space.
Probably Insulation...
No. The trapped air gives you your insulating value. When you squeeze the old and new together you will not gain anything.
The best place to look for this type of work is in the yellow pages of your local phone book. Insulation companies are usually local and are not worldwide.
As the climate differs from region to region, so do the code recommendations for basement insulation. The recommended R-Value for a particular region will help determine which type of insulation, if any, should be applied. There are however some things to be considered when insulation below grade structures: You need moisture proof, mold resistant inorganic insulation materials. Preferably nothing that looks and feels like a sponge and seems prone to soak up water. Basement wall systems insulated with rigid waterproof foam board, are usually the best options.
IBP seems to be a reputable home insulation company in the DC area. Their website is located at http://www.ibpteam.com/home-insulation-in-washington-dc.asp, and has all kinds of useful information.
Might be an idea to tell us the SIZE of the basement to start with.
The best insulation to use is spray foam, although it is an expensive option. Another option that is less expensive is 1" rigid foam board. Both of these options eliminate the need for tar paper or a vapour barrier as they are self-sealing applications. Avoid using batt insulation w/vapor barrier in basement applications as condensation may occur which will encourage mould growth.
Usually with a piece of insulation fitted between the joist, top of the foundationand the floor.
You could friction fit some 3/4" Dow styrofoam on the inside frame during wintertime.
In an event of a basement flood, one should notify their agency if the damage is covered. One should also remove and replace damaged drywall, insulation, mechanical fixtures, and electrical material.
See http://www.mass.gov/Eeops/docs/dps/780%20CMR/780061.pdf