We were recently quoted several prices on added a 14′ x 30′ three season room to the back of our converted duplex. The prices ranged from about $20,000 up to $50,000 without the roofing (shingles & tie in to existing roof).  This was quite discouraging since it is not all that complicated to build for the average do it yourself woodworker. So, I set out to design my own set of plans to build a three season room to save a substantial amount of money. I have already built two garage structures and or course our entire home bar and home theater areas in our basement, so how hard could it be?
The first step is to develop a detailed design from the foundation to the top of the roof. The foundation is the most critical aspect of this type of project, so you may have to get a professional involved. I also suggest you open the phone book and have a few contractors come over to discuss the project. Who knows, you may get a super cheap deal to build it for under about 15k, but I’ll show you my  plans that can havie it built for well under 10k. In fact, my material cost for the base structure is about $4,000.  The roofing, which I hired a contractor to do will add another $3,000 for a total base price of $7,000. This does not include windows and doors which will add another $2,000 or so. The interior finishing will be stretched out over time  as the base materials are paid off.

You can follow the entire building process by clicking the “Three Season Room Project” link at the top of this post and by using the page navigation at the bottom of each page. Thanks & Have Fun!