Bars are used, which

To fix the inclined bars to the beam, additional (auxiliary) bars are used, which are fixed with metal brackets. The very important point is the observance of the horizon of beams, when it is violated, it is necessary to correction by laying the planks. Beams are made of coniferous wood, wood should be well dried and without visible damage. The thickness of the beams should be at least 1/24 of its length.