Here are four signs of an unventilated or under ventilated attic.
Attic too small get soffit vents.
Soffit vents come in several sizes and styles including small round discs and rectangular grilles.
This is called passive ventilation.
Touch your ceiling on a warm sunny day.
Butt a cardboard template against the fascia and mark your soffit hole locations to begin.
Ft you divide that by 150 to get 10 sq.
These vents allow outside air to enter the attic at the lowest point of the roof along the underside of the eave.
That said air resistance and interference such as vent grates reduces the area of true ventilation.
If the attic ventilation system is not a balanced combination of intake vents installed in the soffit under eave or at the roof s bottom edge and exhaust vents installed at or near the roof s peak the attic ventilation system will not be efficient and effective.
Add soffit venting first.
In other words the entire vent opening doesn t count as vented space.
Is this too much ventilation.
A well ventilated attic offers four benefits.
Of vent for every 300 sq.
In order to facilitate this exchange of warm and cool air the general rule of thumb suggests installing at least 1 sq.
If you don t see any attic vents on the roof or in the eaves you need to add some.
They re most effective when used in conjunction with a continuous ridge vent.
I live in north carolina.
Of vent space for every 150 sq.
If your home is fitted solely with small gable end vents or a ventilator high in the roof you might want to consider adding soffit vents to increase airflow.
This is one home improvement task that is well worth undertaking.
Also should the vents to the crawl space.
Generally speaking you need a ratio of 1 300 where for every 300 square feet of ceiling space you need 1 square foot of attic ventilation.
Building codes vary.
Here s how to keep the air moving with soffit vents.
Look at your eaves and roof.
It prevents mildew growth and rot on your roof s framing and sheathing by.
So if your attic is 1 500 sq.
A hot ceiling tells you that the attic is acting like a solar oven.
If you re lacking good attic ventilation installing a soffit vent where needed is a no brainer.
The most common way to add ventilation to an attic is by installing air intakes in the soffits and putting an outlet at the gable of the house.
This creates a natural air flow by drawing in the air from outside pushing it up and out through the vent at the top of the house.
