Q: We are scheduled to get a new roof in a few weeks, and I need some ideas on attic venting. The roof salesman said he would install a ridge vent. Will that work on a hip roof with no overhang? I have read that a ridge vent needs soffit vents to work.
A: Looking at a box-style home similar to yours without soffit or overhang vents, installing a ridge vent alone would be, in my opinion, a bad idea. A typical-sized home in your neighborhood, without soffits vents, would need approximately 43 lineal feet of ridge venting. That’s not possible on a home with a hip roof design where there are only about 8 to 10 feet of ridge available that can be vented.
According to the website cor-a-vent.com, “a ridge vent can only be used in conjunction with soffits vents.” The website goes on to offer a solution with a product called In-Vent. Where there are no soffits to vent, you could ask the roofing contractor to install an In-Vent system that is applied on top of the shingles, down low, near the bottom of the roof. The location of the In-Vent system will depend on the weather conditions in your area. The In-Vent system will give you the proper intake ventilation for the ridge vent.
Without an air intake system, the ridge vent could allow rain or snow to enter the attic space damaging insulation, personal items or the ceilings below. Vent systems such as turbines, box vents and power vent fans that are used without soffit vents can actually pull conditioned air from inside the home. A properly vented roof attic space can help save on energy costs and extend the life expectancy of the new shingles. It is important to do it right this time while new shingles are being installed.