I did residential install for 5 years and now work for an MEP mechanical engineering firm designing large commercial systems. (just to give you an idea of my background)
First off I would not reccomend soud lined (internally insulated) ductwork. Although many swear that it does not cause any problems I have seen far to many systems designed improperly and create mold and air quality issues. In alot of cases (not always of course) but sound lined ductwork can be more expensive as well.
As far as the space pak systems mention above I have personally installed alot of these and the best application for tis system would be in older homes that currently do not have any ductwork. The higher velocity of the system helps cut down on duct sizing by using there essentiall proprietary duct tubing. It works well when "knee walls" are available and the central unit is in an attic. Since you have a gas furnace and ductwork already I wouldnt reccomend the space pak system.
From the sound of it (depending on the age of your furnace and space limitations) the comment above about adding a coil and condensing unit is probably the cheapest and easiest route.
Where abouts are you located? I could reccomend the company I used to work for if your looking to go thorugh an actual company of depending on location I know several people that work for contractors that do work on the side. It all depends on what exactly your looking for.
First off I would not reccomend soud lined (internally insulated) ductwork. Although many swear that it does not cause any problems I have seen far to many systems designed improperly and create mold and air quality issues. In alot of cases (not always of course) but sound lined ductwork can be more expensive as well.
As far as the space pak systems mention above I have personally installed alot of these and the best application for tis system would be in older homes that currently do not have any ductwork. The higher velocity of the system helps cut down on duct sizing by using there essentiall proprietary duct tubing. It works well when "knee walls" are available and the central unit is in an attic. Since you have a gas furnace and ductwork already I wouldnt reccomend the space pak system.
From the sound of it (depending on the age of your furnace and space limitations) the comment above about adding a coil and condensing unit is probably the cheapest and easiest route.
Where abouts are you located? I could reccomend the company I used to work for if your looking to go thorugh an actual company of depending on location I know several people that work for contractors that do work on the side. It all depends on what exactly your looking for.