Ask for the manufacturing method of I-beam attic with main beam.

You haven't arranged the main beam and the secondary beam. I suggest that the main beam should be built in the east-west direction so that the secondary beam can be built in one direction. Besides,

For a span of 3.9 meters, if the labor consumption of 12 is a little too little, the beam can extend into the wall with the supporting length of 150. For stability, beam pads can be added at the beam ends. Decoration can only be sealed with cement mortar, without concrete. It is suggested to build a thin wire mesh.

No ring beam is needed, and the secondary beam and the main beam can be connected by welding.

The range of 600 is a little too close. I wonder if there is a wooden structure or something on the beam.

For reference, you can contact me online.

If you want to build a board, you should make it into a well-shaped grid. You can determine the interval according to the size of the wood and the number of blocks that are just divided into. The requirements are not high, 600 will do.

If it can only reach 78 cm, it is a little small, and it is best to reach 9 10 cm. If the neighbor's house is not decorated, you can consider digging it through and repairing it.

It is ok to have sand in cement mortar, but you should hang barbed wire when plastering to ensure strength.

If you work at intervals of 600 12, you can board the board directly. Angle steel just covers the board, and the angle steel span of 5 should not be greater than 800. As for the interval, it depends on how big the chessboard can span.