I have a 1000 s.f., circa 1930 lap wood siding house that is two stories with no gable or soffit vents and the roof is metal. HVAC is a wood stove in the winter and two window AC units for the summer. Location of the house is the middle of Virginia in the country. There is no insulation in the house, except in the renovated bedroom and kitchen. To the best of my knowledge I do not have a mold problem and there is no rotten wood from condensation.
My problem is the upstairs is terribly hot in the spring, summer and fall as the day gets going the metal roof heats up. The larger attic spaces are to the left and right of two rooms upstairs, the true peak attic is only about 16 inches tall above the rooms. There is no insulation envelope separating the house's living area with the attic spaces.
Due to the house design there are no soffit vents. The vents in the house are cracks that were not caulked.
Multiple questions: were houses in the 1930's built without ventilation because of all the cracks?
I plan on cutting holes in the siding and installing gable vents on opposite ends of the house, they will have about 160 square inches of true ventilation space, will gable vents create any unintended consequences?
Will passive venting work with the gable vents or should I also install a gable fan?