Garage Roof Trusses Spacing

While this article focuses on configurations we also have a very cool set of illustrations showcasing the different parts anatomy of roof trusses.

Garage roof trusses spacing.

If you plan to heat the garage and insulation is to be placed between the rafters the space must be wide enough to provide for the thickness of the insulation. In a garage the garage roof truss spacing is usually made in accordance with the local building laws after all a garage is an occupied space as much as a house is. I have this above my own garage. The same concept holds true for roof trusses.

8d ring shank nails should be used instead. The horizontal bottom chords of most garage trusses are designed to carry the weight of drywall and insulation. The run or the base number is 12 inches. Pitch slope the pitch or slope is the incline of the roof expressed as a fraction describing the rise over the run.

Scrap of plywood over the chords and set about 40 lbs. Rafters are placed at 12 16 or 24 inch intervals. The typical thickness range for sheathing is 3 8 to 3 4 inch. For example a slope of 6 12 means for every 12 inches of horizontal distance the slope of the roof will rise 6 inches vertically.

In terms of how this generally operates it is worth noting that that too is with the same two by four material and the trusses are also going to be around the same spacing that is twenty four inches off centre. If interior moisture were improperly managed for example if a clothes dryer were vented into a finished garage area instead of to the outside a 16 inch on center truss spacing would be more forgiving of the bad practice. Of stuff on it. The trusses should be a little longer than the exact width to allow for overhang and you will need sufficient trusses to mount across the length.

Sheathing should be a minimum of 19 32 inch thick. Once you ve calculated the number of trusses you will need you should purchase the lumber. Is a safe estimate. Just as there are many types of roofs with many roof parts there are many different types of roof trusses this extensive article explains through a series of custom truss diagrams the different truss configurations you can use for various roofs.

Check your local building code for the specific interval as it can vary by area. Most are spaced between 18 26 inches apart. Roof sheathing comes in grid marked 4 by 8 foot sheets and should be installed perpendicular to the frame. Common spacing for trusses on this type of building is often between 2 and 4 feet but trusses built with advanced designs may allow spacing as great as 8 or 12 feet.

Never attach roof sheathing with staples. Look at this photo of the space created by attic trusses at my home. The rise will be the elevation change over the 12 inches. Attic trusses have a rectangular shape inside each truss.

If the roof slope is steeper than 9 inches in 12 inches of run it doesn t take much width to end up with a nice room 12 feet wide with an 8 foot ceiling. But in general it doesn t matter if the truss spacing is at 12 16 or 24 inches. So the space between rafters can be greater without reducing the maximum span.