How To Build A Roof Over Concrete Block

The steel bar joists are l shaped so the blocks have a flange to sit on.

How to build a roof over concrete block.

Attaching a wood roof to a cinder block building is difficult but possible. You can either use removable concrete forms or forms that are made of concrete and insulate the house. Place empty cement bags down inside the cinder block cores so that the concrete will fill only four blocks rather than the entire cinder block wall. There are two ways to make a framework for a flat concrete roof.

The steel joists will provide a strong foundation for the flat concrete roofing. The bottom of the joists should rest on either a beam or a wall. A string and level is all you need to tackle this. The flat concrete roof itself can be up to 7 inches thick although the greater the thickness the more the concrete will need be poured in increasing numbers of layers with each.

Use a framing square against one side of the first anchor bolt set the square against the lumber and draw a line against the square locating the one side of the bolt. Rest the blocks between the 7 inch joist pairs up against each other. Independent block company will delivery if you buy enough. As the width of the concrete slab is 16 3 4 inches place the steel joists at this distance.

The masons build the corners first and ran a level string line between the corners to lay their block. 8 inch block is not that heavy. Place a 2 by 6 foot piece of lumber on the top of the cmu block with one end flush with the corner. This will give it the support it requires.