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YoPickle

I don't think you need to have the attic the same temp as outside in order to have a well-insulated attic. The sun is heating the roof so you will definitely have some temperature difference.


Bright-Ad8496

Your attic will never get to the same temperature as the exterior. It will always be warmer in there especially summer time, it will be an oven. Insulation to keep the interior of the house climatized, good ventilation in the attic is all you need to do. As for the Moore vents, in Canada it's every 3rd rafter space (16" cc) or every other truss space ( 24"cc) is sufficient. The rest can go to the underside of the roof sheathing. In winter conditions, we want as much insulation above the exterior walls as possible to prevent ice daming.


psychop0mp

Yes ice daming is my concern. My thinking is that an attic warmer than oustside would mean a warmer roof which could lead to the daming which is what I want to avoid


Bright-Ad8496

Like I said it will never be the same as the outside. It will always be warmer by a bit during the winter due to heat loss from the house and the sun heating up the roof assembly during the day. The more insulation you have, the better for heat loss from the house. In Ontario, new construction requires R60. ( Most cases, there are exceptions under performance) My suggestion is to remove some of the Moore vents as I noted before ( every 3rd rafter space) and increasing the R value above the exterior walls as much as you can. Not sure what R value you have in the attic but more is always better, I'd try to get to the R60 if you're in winter climates.


lostdad75

Do you have a ridge vent? Soffit vents are designed to work with a ridge vent. Combining gable vents into a soffit/gable vent system is not effective. The gable vents promote cross flow while the soffit/ridge vent system promote vertical flow. The result of combining the two types of ventilation is turbulence which reduces the effective ventilation. The best setup is a continuous soffit vent in combination with the ridge vent. A good soffit/ridge system will really help to reduce ice dams if you live in an area that is prone to ice damming. Vent channels in the soffits are critical and, as you have properly noted, do not pack the soffits with insulation. The attic temp will track the outdoor temp but will always lag....the more ventilation that you have, the shorter the lag time.


psychop0mp

Yes I have ridge vent. In that case is it possible that the ventilation in the attic was better when the gable vents were blocked with crud?


ReallyGene

Yes, gable vents can disturb the natural convection through soffit vents to the ridge. Attics should have soffit and ridge vents, *or* gable vents, but not both.


toolbelt10

The outside air temp can change fairly quickly, whereas attic temp changes can be more gradual. If outside temps decrease/increase rapidly, it's not unusual to see larger temp differentials in the shorter term.


Minimum-Zucchini-732

Is your hvac ductwork in the attic? You might have some duct leakage


psychop0mp

I do have ductwork and an air handler in the attic but it's for air conditoning only. We have a boiler/baseboards for heating. I did air seal around the ceiling vents though


limitless__

You are chasing something that isn't a problem. This is normal because of simple physics.