Hip Roof Ventilation Requirements

Always have a balanced ventilation system.

Hip roof ventilation requirements. 2018 international residential code. On the upcodes website. Federal housing authority recommends a minimum of at least 1 square foot of attic ventilation evenly split between intake and exhaust for every 300 square feet of attic floor space. One contractor is recommending 2 attic fans and a ridge vent one is recommending 1 attic fan and a ridge vent and one is recommending 1 attic fan and 2 box vents.

You could require compensating with additional exhaust. A full 4 sheet with wafer cuts showing top and bottom uncut for 6 to gain cross strength. 2018 international residential code. Hip vents get wafer cuts of 12 with 6 solid plywood intervals step 2.

On the upcodes website. Exhaust intake of 50 50 requires 17 5 feet which is insufficient but i see some say 40 60 is acceptable and this then reduces to 14ft. In no case should the amount of exhaust ventilation exceed the amount of intake ventilation. And in many of these cases the hip roof forms a large volumetric attic space to ventilate.

Figure 7 mechanical ventilation used with a hip roof. One method is to use a powered attic vent with a humidistat thermostat located close to the ridge or top of the roof. Of course there should be intake vents to ensure a balanced system. Calculate or enter the square footage of the attic or area to be vented.

Chapter 8 roof ceiling construction. Contains sections covering roof framing roof sheathing and roof ventilation. What is the optimal ventilation for a hip roof we have a hip roof in need of replacement and there is discrepancy in the ventilation suggestions. Foot requires cobra exhaust vent structure of 17.

Roofer is recommending ridge vents and uses gaf cobra which has 16 9 nfa per lineal foot when hand nailed. Chapter 9 roof assemblies. A number of problems that could come up when trying for the ventilation of hip roofs is able to be that there s possibly not sufficient exhaust ventilation.