Depending on the layout of your house and the direction it faces concerning the add on room, it can be beneficial to your home. Besides being a nice "outdoor room" in the warmer months, done right, it can be a heat collector and warm a portion of your home on sunny winter days.

just what is a "four seasons" room. anything like a sunroom?

I guess it is the same thing as a sun room.

its one of these http://www.fourseasonssunrooms.com/

I've been kind of struggling with whether its a good idea or not. I really like the idea of it just want to make sure its actually as good as it sounds and doesn't suck the heat or air conditioning out of my home.

You might consider havin it custom built for your areas seasonal requirements. I built on for some folks using french doors mounted fixed under an existing patio and ran reflective foil faced foam panels under the concrete and topped with tile for the floor covering. The incoming rays in the winter warm the room by the heat not being absorbed in the slab, but rather reflected back into the room. i installed double french doors on either side for access, the rest were single doors fixed making window walls. You might consider not having the open pane windows for the roof, but rather a typical framed, insulated, and roofed cover. That is where most of your heat escapes, As far as cooling, reflective pull down shades and in both cases winter and summer, you will want well insulated glass panels. The room i built they have drapes to keep the summer sun out. There are many ways to construct it so that cooling and heating the room wont break the bank if designed right for your area.

I worked for a builder where we constructed panels that filled with styrofoam beads when you wanted insulation with a vaccum system that removed the beads when you wanted full sun. There are many avenues, do your research and you can have a room that benefits your home, not deprives it concerning energy loss.

Thanks. That was a great post. Sounds like it can be great if done right. Time to start investigating...

I live in Anchorage, Alaska and had a Four Seasons Sunroom added last fall. It's the cathedral style, with a glass roof, and all but the bottom 22" of the three walls are windows that slide open. I chose Duraceramic tile flooring, set on the diagonal--toasty on the toes, without the hassle/expense of radiant in-floor heat. The room has Eastern, Southern, and Western exposures. The hot water baseboard heat registers were extended into the room, and it stayed plenty warm all winter. Catches the summer breezes now. Be sure to install a ceiling fan, which helps circulate the air in all seasons.
The rooms has LOTS of light, and we can see the Northern Lights thru the glass roof in the winter. I love it. Hey, if it stays warm up here in the winter, it should be balmy in NJ!

Why are you considering something you haven't experienced before? Personally, I love them and believe they add value to the home. But I would get out there and see some before deciding to rip an exterior wall off my home and construct one. Surely someone in New Jersey has one that you can see.....

You say you have a family member who installs them. Doesn't he have one??

I don't like cleaning all the glass and prefer a plain shaded screened porch for summer with a sunny patio so I can take my pick. Preferably with a living room with a big window that faces south in winter which is good enough for me.
I just got back from an open house where they turned the garage into a family room. Second one of these I've seen.
I hate not having a garage. And I want an attached garage.
Just FYI from those of us trying to find a house to buy.