Structural Analysis for a Wood House

Components

• The wood house should be considered as a single structural unit. This is mostly because, while construction normally goes according to a piece-by-piece approach, the house itself is tightly bound by each of its components. Simply put, these components are floors, walls, roofs and stairs. These components chiefly function as a way to handle different kinds of loads.

Wood Variables

• For wood houses, moisture content, shrinkage and changes in temperature are central concerns. Since wood is organic, it is not as predictable as steel, though the “grading” system has removed some of this by classifying certain types of wood as stronger than others. Moisture and temperature can have a great impact on the density and integrity of the wood used in construction.

  Much wood is kiln-dried at the lumberyard to increase its density and remove any unwanted moisture that can harm its inner core density. Local building codes are strict about the nature of different wood types and their moisture content. Too much moisture will give a wood that can be elastic but ultimately too weak to handle loads. Wood that has been dried too much can be brittle and will not give at all.

Equilibrium

• While wood and steel are close in total cost, wood is much easier to work with. It can be manipulated, sawed and changed on site, while steel is mostly prefabricated at a factory and shipped to the site. Wood wall and floor frames are designed to create a state of “load equilibrium,” where both pressure exerted and pressure received are equal. To some extent, the pressure in the house is one of the forces holding the units together. Equal force, in other words, lies at the center of the integrity of the house.

Wood Grains

• Wood, especially in the highest grades of durability, can adjust to different loads -- become elastic -- far better than steel or other alternatives. It is slightly cheaper as well. One of the central structural characteristics is the direction of the wood grain. Wood breaks easier if the pressure is moving in the same direction as the grain. Therefore, the load-bearing quality of wood is increased by making certain the grain goes against the pressure, whether this is in the floor or the walls.

Load Types

• “Dead loads” is a term that refers to the constant pressure on the wood framing and joists. Dead loads include furniture, insulation and carpeting. Builders can easily use the proper wood for dealing with dead loads. On the other hand, cyclic loads are those that change regularly. These include things like snow or wind. Under certain circumstances, building codes will mandate that the “load-bearing” nature of the wood must be a certain proportion of the total equilibrium pressure of the house.