Ridge Vents : why are they better than can vents?
When it comes to ridge vents there are some things to consider. Not all homes should have a ridge vent on them. It can sometimes cause a problem with proper air flow in the attic or a leak depending on how the air flow is set up in the attic. In most cases, the older the house the worse the roof design for proper air flow. The industry had to learn over time the importance of proper air flow and how to do that.
Ridge vent is designed to work in conjunction with soffit vents on your overhang. The soffit vents allow fresh air in the attic. As the hot air rises in the attic, the ridge vent at the peace of the roof releases the hot air. The whole idea is to keep the attic cool. If there are no soffit vents or the soffit vents are blocked by insulation or wood and you put a ridge vent on, the ridge vent won’t work properly. It can also cause what is called negative air flow which can cause rain or snow into the attic.A good rule of thumb is to check and see if your soffit vents are working properly is to poke your head in the attic and look at the end of the roof line and see if there is any daylight coming threw the overhang. If not, then your soffit vents are probably blocked and I would not install a ridge vent.
When you know that you have proper air flow coming into your attic and can put a ridge vent on, you then have to make sure you put one on that works properly and is installed properly. There are some ridge vents that work better than others and some that I have seen leak due to improper installation or poor design of the product. If the cut at the peak of the roof for the ridge vent is made too wide it can leak. If the opening is made too small, then you want to release enough hot air. If the ridge vent is not nailed down properly, it can come off the roof. If the ridge vent does not have a baffle at the bottom of it, it wont work as well. The baffle is used to help suck the air out of the attic.
Ridge vents can not be put on if you have can vents on the roof. If you put a ridge vent on and leave your can vents in, the ridge vent will not work properly. You have to take the can vents out and fill in the holes properly with new wood and shingles before installing the ridge vent. If the ridge vent is installed properly it is better to have then can vents. The can vents only release hot air where the can vents are located. The ridge vent will release hot air from end to end of the peak of your roof, which will help keep the attic much cooler