Quck answer
To calculate soffit requirements for a home, follow these steps:
1. Measure the length of each eave where soffit will be installed.
2. Multiply the length of each eave by the width of the soffit panel to determine the total square footage needed.
3. Take into account any corners or angles, and add extra square footage to cover these areas.
4. Consider any overhangs or protrusions that may require additional soffit panels.
5. Determine the type of soffit material you will be using (e.g. aluminum, vinyl) and its coverage area per panel.
6. Divide the total square footage needed by the coverage area per panel to determine the number of panels required.
7. Purchase the necessary amount of soffit panels, taking into account any extra material for waste or future repairs.
By following these steps, you can accurately calculate the soffit requirements for your home.
Every sloping roof extends over the side walls of a building. The purpose of this extension, called the eave, is to protect the walls from rain. The underside of the eave is usually covered with paneling known as soffit, although in barns and sheds it may be left open.
Soffit is the material that covers the area between the wall and the outer edge of the eave, which is usually covered by a decorative fascia board. While you can make your own soffits out of plywood or wood planks, it is more common to purchase ready-made soffit material. However, you need to calculate the amount of material required.
Measuring Soffits
Calculating the amount of soffit material needed is usually straightforward. First, measure the distance from the wall to the fascia board. Then measure the total length of the fascia. Multiply these measurements to determine the total square footage of soffit material required. If you have a complex roof shape, you may need to make multiple measurements and add them together.
When purchasing premade soffit material, it is typically available in boards of precut widths. Most manufacturers provide a calculator on their website to help you determine the number of boards needed based on their width. You can choose between 12-inch and 16-inch boards, with wider ones being suitable for wider eaves.
Soffits and Ventilation
Homes with soffits usually have attics, which require ventilation. While exhaust vents on the roof or gable vents allow hot air to escape, cool air must enter the attic for proper circulation. This is typically achieved through the soffits. In a balanced ventilation system, cool air enters through the soffits, heats up in the attic, and exits through the roof or gable vents.
After the soffits are installed, soffit vents are cut into them. These vents can be individual openings covered with rectangular or round grids, or continuous vents that are longer and narrower. The number and size of the vents are crucial for effective attic ventilation.
Calculating Soffit Vent Area
The ventilation space in the attic is determined by its floor area. The code requirement is that the total vent space should be 1/150 of the attic space. If the system is balanced, with exhaust vents comprising 40 to 50 percent of the total venting area, this ratio can be reduced to 1/300.
To calculate the soffit vent space, divide the floor area by 150 or 300, depending on the system. Then divide that number by 2, as the venting should be equally distributed between the roof and soffit vents. Once you know the total venting area, you can determine how many units of vents you need to install, based on the venting capacity provided by each unit, which is usually indicated on the packaging.
