THE BELVEDERE - Structural Considerations

Due to height and appearance considerations, the Belevedere floor will be dropped into the top of the attic space, as the attic has close to ten feet of height in it at the flat center section, which is unnecessary. Dropping the floor also lowers the height of the belvedere as it sits on the flat roof when viewed from the outside of the house.

  Pictured above is the entire dropped floor of the belvedere, which has to also replace the entire structure of the original flat roof box that is being removed.  2 x 6 collar ties from rafter to rafter, glued and nailed, plus double ties and brackets supporting box ends for the opening to the belvedere can all be seen here.

A close up looking to the right of the box, showing attic rafters with vents in place, the end of the double collar tie, and some of the stub ties that connect to the new box opening.

THE BELVEDERE - Structural, Removal and Replacement of Floors, Framing

Looking toward the front of the house, the south wall and half the west wall are visible. The belvedere sits on top of the old flat roof portion, which has been leaking over the last few decades, as evidenced by the water stained and damaged timbers.  The old flat roof and structure is in the process of being removed, now that the new structure and belvedere floor has been installed underneath.

Looking toward the rear of the house, giving a better view of the size of the belvedere. There are two windows at each of the north and south ends, and four windows on each side, in a room that nominally measures about 6' wide by 13' long.  The shop vac is sitting on the new sub floor, which is supported by the joist and collar tie structure below.  A built in window seat will be installed in each end of the belvedere, the basic supports of which can be seen behind the shop vac.

FRAMING - Third Floor Bath

Looking to the rear of the house, the attic staircase is on the left, the door opening to the bathroom directly ahead at 45 degrees, on entering the bathroom, hard left to the toilet, hard right to the urinal, and right and ahead to the vanity, in an asymmetrical T shaped layout.

Some insulation detail, the vanity is to the left of the valley, the urinal to the right, insulation is a styrofoam rafter vent, 2 x 6 Roxul insulation, followed by 3/4" Atlas XPS rigid foil backed 3/4" sheet.

CEILING FRAMING - Collar Ties and Structure

Looking to the front of the house, I have added a 2 x 6 box directly beneath the flat roof box, and collar ties have been cut and installed between opposing rafters, glued and nailed in place, and bracketed underneath the new 2 x 6 box. These collar ties are effectively the new ceiling joists for a slightly lower ceiling in the attic (about 8'4") and the floor joists for the proposed belvedere above.

Looking to the rear of the house, showing  two of the collar tie joists, blocking, short T joists butting into the first cross joist, and shorter collar ties down the narrow section of the attic. The wall framing in the background are the walls and door to the attic bathroom.