Roof Truss Design: 4 Types to Consider
A roof truss is a structural frame designed to harness the inherent tensile strength of a triangle. Engineers have always known that triangles have better structural stability than other geometrical shapes. For this reason, trusses are the most suitable frames for a roof's foundation.
Many kinds of trusses exist for the roof. Each one can influence the overall design and appearance of your home. Here are the most popular roof truss types that you can consider for your home.
Raised Heel Roof Truss
This type of roof frame can allow full insulation in the attic, which can extend to the area where the top edges of the walls intersect with the roof. Raised heel trusses are ideal because they provide a barrier on the eaves of the roof, thus allowing a more efficient air circulation in the attic. Air circulation prevents moisture and the growth of molds. Furthermore, by allowing the full depth of insulation to extend to the wall edges, raised heel trusses make homes more energy efficient.
On the downside, this type of roof truss can cost a bit more than conventional ones. The design of the frame requires more materials on the undersides of the structure. Also, since you can extend insulation to the walls, you'll need more insulating materials.
Scissor Roof Truss
If you want a cathedral ceiling for your home, the right roof frame for you is the scissor truss. This type of truss is shaped like a glider. The chord is lowered and sloped inwards. With scissor roof trusses, you do not need a bearing beam and wall.
But there is one drawback to this type of truss, and that is cost. Scissor trusses tend to be more expensive to manufacture than conventional trusses. Insulation materials can also be difficult to install with this kind of roof truss.
Parallel Chord Truss
Like the scissor type, parallel chord trusses can also be used for home designs that require cathedral ceilings. But one big difference is that parallel chord frames allow you to install insulation materials a lot easier. This type of truss is made with both wood materials and steel braces. The steel braces may cause inefficient heat flow in the attic. This is called thermal bridging, and it can bring down your home’s energy efficiency.
Conventional Roof Truss
If you are on a tight budget, having your trusses customized may not be a wise idea. To save on manufacturing and installation costs, you can always go for the conventional roof truss which has the unmistakable and basic shape of a triangle.
Unlike in other roof truss designs, the structure of the conventional truss is dictated by the spacing of the trusses, the area you need to cover and the weight of the roof on top of the truss. Conventional trusses can be pre-fabricated and are a lot easier to put up.
Always remember, there are many types of trusses. You can use one or a combination of truss designs.