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Typical issues & errors during Roof Ventilation Alright so as the title suggests, this article is all about roof ventilation. We receive a ton of requests where clients ask our expert opinion on what are the most common issues and errors with roof ventilation, therefore as a leading contractor for Roofing Charlotte NC it is our prime responsibility to spread awareness on the matter. Asphalt shingle manufacturers require roof ventilation to help preserve the life of the shingles, despite the fact that the colour of shingles will have a greater effect on their life expectancy than roof ventilation will. An attic with insufficient ventilation will get warmer than a well ventilated attic, which may increase the temperature of the shingles, which may decrease the life of the shingles… just a little. Proper ventilation will also help to keep the attic space cooler during the winter, which may help to prevent ice dams. Let me say that again; proper ventilation may help prevent ice dams. I’m not saying it will, but it might. The same thing goes for frost in the attic; proper ventilation may reduce frost accumulation in attics, but it won’t prevent it.


In other words, roof ventilation certainly isn’t a cure for any condition, but it’s still required. Roof vent manufacturers publish installation instructions that are easy to read and should be easy to follow, and roof ventilation is required in section R806 of the building code, but a lot of folks either don’t read the instructions or they don’t care. Today I’m going to go over a few of the most common roof vent installation issues. Weather in Charlotte NC can be surprising therefore you want to ensure ventilation system on your roof is intact. To avoid potential damage to your home and finances, it’s important for you to know the basics of roofing ventilation, and choose an installation expert for roofing in Charlotte NC that knows how to properly ventilate your home’s attic or rafter system. Condensation


Condensation – when water vapour cools and becomes a liquid – can occur inside homes and buildings, and often leads to damage and deterioration. Condensation can occur when there is high interior humidity and the temperature of interior building components is at or below the dew point temperature. Condensation that forms inside home attics and buildings can be caused by the use of washing machines, dish washers, bathtubs, showers, tumble dryers, humidifiers, hot tubs, and swimming pools unless these items are properly ventilated. In many instances the condensation is bad enough to be mistaken for a roof leak. Condensation can be eliminated by one, or a combination, of the following: • Reducing or eliminating the source of moisture. • Raise the temperature of interior surfaces above the dew point temperature (this temperature will vary, depending on the relative humidity). • Install proper ventilation. Mixed Exhaust Vents For proper ventilation, both high and low vents should be installed, most contractors for roofing in Charlotte NC seem to overlook the importance of mixed exhaust vents. On paper, the high vents are supposed to act like exhaust vents while the low vents should act like intake vents. Convection is supposed to help make this happen. In reality, it all depends on how the wind blows, convection has little to no effect, and it’s never perfect. The intake vents will typically be soffit vents, while the exhaust vents may consist of ridge vents, turbine vents, box vents, or powered vents… but only one of those. The photo below shows an example of these different types of vents, all installed on the same roof, which is a no-no.


When different types of roof vents are installed, there is an increased potential for air in the attic to basically short-circuit. In the photo above, the power vent would probably end up sucking in air from all of the other high vents in the photo, while pulling in just a small amount of air from the lower soffit vents. The solution here is to install only one type of exhaust vent. Crooked Turbine Vents I’ve never been a huge fan of turbine vents because I have it in my head that they may end up causing some of the same problems that powered roof vents do. The one thing I’ll mention is that turbine vents need to be installed perfectly level; when they’re not installed level, they don’t turn. In the photo below, the vent on the left wasn’t level. Do you see anything else that’s wrong in the photo?

The other thing about turbine vents is that they really do pull air out of the attic; if air sealing hasn’t been performed in the attic, they’ll pull air into the attic from inside the house, and shouldn’t be used. That bears repeating: do not install turbine vents if the attic has not been professionally air-sealed.


Insufficient intake vents Current standards specify a 50/50 split between high vents and low vents, but how are low vents supposed to be installed in a house with no soffits?

You can ask a lot of companies for roofing in Charlotte NC and yet the answers may not satisfy you. We got you covered here, you see, without any low vents, the high vents will tend to pull conditioned house air into the attic through attic air leaks. One solution would be to install fascia vents, and another less desirable option would be to install a bunch of box vents low down on the roof. What’s the Best Type of Ventilation? Attic ventilation is an important part of roofing. Proper attic ventilation extends the life of a roof and reduces problems because it minimizes the temperature differential between the attic and the air outside. Proper ventilation will remove moisture and heat from the attic. Trapped heat and moisture can raise energy costs, cause ice


dams, and damage roof system components as well as structural and personal items located inside the attic where temperatures can easily reach 150° F (65° C). The best type of roof ventilation for most homes occurs when cooler air can enter the attic through soffit or fascia intake vents. These vents can be seen from the ground and are located behind the gutters. As the cooler air warms and rises, the warm air is vented out through exhaust vents mounted on or near the top of the roof. Both intake ventilation and exhaust ventilation installed at an approximate one to one (1:1) ratio are required for maximum air circulation. One square foot of ventilation per 300 square feet of attic floor space is a general guideline and is a code requirement in some areas.

Free Roof Inspection If you have more questions on ventilation errors or other issues related to roofing in Charlotte NC get to https://www.alphaomegainc.com/ you can also schedule a free, no obligation inspection, consultation and estimate.

Typical issues & errors during roof ventilation  

This PDF contains detailed information about Roof Ventilation. If you are going for roof Ventilation must read this PDF, its help you a lot...

Typical issues & errors during roof ventilation  

This PDF contains detailed information about Roof Ventilation. If you are going for roof Ventilation must read this PDF, its help you a lot...

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