I just purchased a 1950's home with a unique roof/ceiling. The ceiling/Roofing in made of 2x4's butted up one to the next to make a 4" thick solid roof. Yes, that's correct no space between the 2x4s. The roof must weigh a ton plus. The top of the solid roof is tar and gravel and the bottom of the 2x4's is the interior ceiling. I have no space inside to create an attic or add insulation, the top of the windows is only 6 or so inches from the ceiling at the walls. No attic, no airspace. The house is located in Tracy, CA where it gets very hot in the summer and with no attic the living space is hot! The slope is probable 2:12 on the roof. I was hoping to insulate the roof somehow. Ceramic roof coating from HY-TECH maybe, but it wouldnít help with heat retention in the winter if the stuff works at all. Could I replace the tar and gravel with shingles and somehow insulate from the top under the shingles. Iíve also seen foam roofing as an option but I canít do that myself. Any help /suggestion will be greatly appreciated.