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How Attic Insulation And Attic Ventilation Work Together

August 23, 2018

A good contractor will tell you right off the bat that the best approach to a comfortable home starts in the attic. The space needs to be well sealed, well insulated, and well ventilated for maximum effect on the rest of the home. This is because – warning: this may sound strange – your attic is not a part of your home’s building envelope, unless it has been renovated and finished into a living space. Your building’s envelope includes only spaces that are conditioned, and play an important role in how you feel in your home.

For professionals, a “truly insulated building envelope” is key to achieving optimum energy efficiency, resulting in less energy usage, lower energy bills, and increased comfort. For this reason, we think of the attic as its own envelope that requires just as much care.

The professional installers at Great Northern Insulation have been trained using these guidelines, so you can expect the best results if you choose us for insulation.

Interested in having GNI assess your attic for free? Click here to schedule your assessment.

Improving airflow and ventilation in the attic

For improved energy efficiency throughout a home, the best results are achieved when attic insulation and attic ventilation work together. It’s not enough to simply load up the attic with insulation materials. The space must be sealed for air leakage and ventilation must be assured.

Your attic intakes air from soffit vents. You may notice them if you look up at the underside of where your roof sticks out over your home. In a healthy, unfinished attic, outside air enters through these vents, follows up a baffle, circulates through your attic, and leaves through a ridge vent, gable vent, or other form of vent, such as a turbine vent (otherwise known as a whirlybird). When there is moisture accumulation in the attic space, this controlled motion of airflow helps to prevent condensation (which can lead to mold) and ice damming.

When there is insufficient or improperly installed attic insulation, combined with a lack of air sealing, heated or cooled air from the living space below can enter the attic and wreak havoc. This could be in the form of moisture damage, ice damming, and increased utility bills. This is also true if your attic is a finished, conditioned living space. In this case, you will want to take extra precautions to make sure the outside air and conditioned inside air do not mix. Either way, air leaving your living space costs you money to replace.

Interested in having GNI assess your attic for free? Click here to schedule your assessment.

Reducing moisture with ventilation in the rest of your home

The symptoms of excess air moisture and indoor humidity are palpable – the home simply feels uncomfortable, regardless of the weather. Windows may fog up, skin feels clammy and worse, there may be a mildew smell. These are signs that something is wrong and remedies are required.

Clearly, reducing humidity levels is a good start – that would be in the kitchen, the bathroom, and in the basement. That requires good local ventilation with high quality vent fans for each appliance or area that produces moisture or steam. Washers and dryers, cooking, and showering all contribute to air moisture. Here, effective venting is essential.

For professionals, the key to managing (and resolving) humidity issues in any space is ventilation and air sealing to control the flow. The fact is, indoor humidity is directly influenced (positively and negatively) by ventilation levels. As such, a professional approach to design and installation will deliver the best performance results overall.

Another concept to consider is that older, leaky homes relied on the leaks to exchange ‘fresh’ air with ‘stale’ air. With your new, air tight home, you need to make sure the air inside is still being exchanged, but at a controlled rate that doesn’t waste your home’s energy. Both HRV and ERV systems ensure that the home maintains accomplish this. These systems use the warm air leaving your home to heat the cool air entering your home during winter. An ERV will also exchange some of the moisture in the exiting air to the incoming air – another plus during winter.

Attic insulation from the experts at Great Northern Insulation

When it comes to installing attic insulation, it’s best to do it right the first time around. As home energy specialists, the team at Great Northern Insulation makes sure that air sealing, insulation, and ventilation are all accounted for when you are considering attic insulation. It’s a three-pronged approach to ensuring optimum home energy efficiency.

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For the second year in a row, HomeStars consistently ranks Great Northern Insulation at better than 95% for customer satisfaction. Thank you again to everyone!

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For the third year in a row, HomeStars ranked Great Northern Insulation at better than 95% for customer satisfaction.

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