The biggest factors that helps in determining the roof truss spacing is weather conditions, material you use for trusses and how you build the roof trusses. When it comes to weather condition you have to keep in mind that either you are living in an area where there is lots of snowfall during the year or having severe hot weather or living in an area of mild temperatures.
This will impact your roof truss spacing accordingly. Other than this if there are high winds then the spacing for roof trusses differs than normal. So the option in this case is to visit your local building authorities and ask them about their recommendation. They will be surely in a better position to tell you the exact spacing required between trusses.
Another factor that will have its impact on truss spacing is the width of building.
This is important to consider and measure exactly, because if you are few millimeters out away from your actual place for truss, it will put immense pressure on that truss. Moreover you must also make sure that the trusses are not too narrow or far from each other. Once you measure the building correctly you will find the required number of trusses to be used.
The material that you are going to use for your roof construction will also affect roof truss spacing. It will also determine how many trusses that you need to put on in specific place. Like if you are using heavy stone material for your roof then it makes roof lot heavier than normal roofs, so it will require more roof trusses to support the extra weight. Similarly if you are using light roofing material than you can support the roof with few roof trusses.
So these are few important considerations that you should follow while determining your roof truss spacing. If you don`t follow any of these then you may land yourself in some serious kind of trouble. Your roof may get a bend which will require repair.
This means that you have to spend extra time, money and material for its replacement or repair. Therefore it is recommended to follow the instructions of local building authorities as well as professional’s advice to construct a beautiful strong roof by placing roof trusses at right places.