Why Does Blocked Soffit Intake Venting Increase heating costs? It's simple. If we make the mistake of providing exit venting from a roof cavity or attic, such as a nice open ridge vent or gable end vents, we also need about twice as much (by square inches) of intake venting at the building eaves. Without adequate ventilation heat and warm air flows into, and is lost from your or attic - warm air rising creates upwards convection currents in your home.
The rate of movement or "strength" of the up-flowing warm air current from your homes occupied (or living) space increases as it enters the attic and finds a ready exit vent at the ridge or gable ends. (We prefer continuous ridge vent to assure even ventilation across the roof deck underside).
As air flows readily out of the exit venting high on the roof (ridge vent or gable end vents) it creates a negative pressure with respect to the air pressure in the building occupied space. However, if there is not adequate intake venting of outside air, that same negative pressure tends to draw still more conditioned air (or heated air) out of your home through the attic.
Essentially we are increasing the heat loss from your home. Conversely, if there are open soffit vents to allow free flow of air into the attic (or cathedral ceiling roof space), the negative pressure or "vacuum" created by the exiting attic air is more easily satisfied by inflowing (cooler, more dry) outdoor air than it is by leaking air from the occupied space. This slows building heat loss during the heating season, and will help keep your energy bills low.
An estimated 9 out of 10 homes in North America do not have proper attic ventilation. Why? Because most people are unaware that attic ventilation can impact the longevity of their entire home! Below are pictures from one attic job we did from start to finish.
To learn more about Proper Attic Ventilation or to schedule a FREE Inspection of Your Attic, please fill out the form below and we will contact you to schedule an appointment to come out and take a look at the health of your Roof and inspect your Attic for Proper Ventilation.
At first it may seem odd to add insulation for warmth and then purposely allow cold air to enter the attic through vents, but this combination is the key to a durable and energy-efficient home.
Here's why: in the winter, allowing a natural flow of outdoor air to ventilate the attic helps keep it cold, which reduces the potential for ice damming (snow that melts off a roof from an attic that is too warm and then re-freezes at the gutters, causing an ice dam that can damage the roof).
Proper insulation and air sealing also keeps attics cold in winter by blocking the entry of heat and moist air from below. In the summer, natural air flow in a well-vented attic moves super-heated air out of the attic, protecting roof shingles and removing moisture.
The insulation will resist heat transfer into the house.The most common mistake homeowners make when installing insulation is to block the flow of air at the eaves. NEVER COVER ATTIC SOFFIT VENTS WITH INSULATION — use rafter vents and soffit vents to maintain airflow.