The minimum recommended slope for a porch roof is 1/4:12, which means 1/4-inch of rise every 12 inches of run. Slopes of 3:12 and 4:12 are more common and provide faster drainage for runoff. Make sure to choose a pitch that’s appropriate both for the climate in your area and the type of roof material you install. Hire a roofer if you need help determining what the right roof pitch is.

Building code allows 24-inch on-center spacing for roof trusses. However, you can install them on 12- or 16-inch centers to handle large loads or other exceptional circumstances. In cases such as covering a wide span or supporting alternative roofing materials, where a structural engineer needs to evaluate or create a design for your trusses, the plans will indicate the spacing. 

You may become so frustrated with the look of moss on your roof that you contemplate whether to clean or replace your roof. Fortunately, you don’t have to go as far as replacing it. After cleaning the moss, you can use a chemical solution to keep it away. For further protection, trim branches that overhang the roof, as fallen seed pods and leaves on the roof allow moisture to collect, encouraging moss growth. Consider adding zinc-coated flashing to the roof, too. As rain washes across the zinc, it leaves zinc particles behind that inhibit moss growth.

Roofing estimates and inspections are not the same thing. Roofing inspections (whether done with a drone or by the traditional method) help you find any damage or defects on a roof. You will pay a set fee for a roofing inspection and use it to get certification or to determine whether repair or replacement is necessary. Beware of unsolicited contractors coming to your home and offering a so-called free roof inspection—these are often scams.

Roofing estimates, on the other hand, are typically free and offered by a roofing company hoping to earn your business. Some roofing estimates are performed with drones, while other companies will still opt to send people up onto the roof. Either way, the estimate is for roof repair or replacement costs the company wants you to hire them for.