Roof ventilation

Why Roof Ventilation Matters

The roof of your home covers the attic space, which is an area we like to think of as the lungs of your house. Your attic is constantly “breathing” in and out as fresh air enters, circulates, and exits to maintain a proper balance of temperature and humidity. This airflow is critical to the health of your home and the lifespan of your roof so proper roof ventilation is key.

Ensure Good Airflow

A properly vented roof will serve to regulate and maintain optimum air temperatures and humidity levels in your attic. Without proper ventilation, stagnant attics become ideal spaces for moisture to collect and mold to form, both of which are unhealthy conditions for your roof, your home, and you! An attic with sufficient ventilation will have equal levels of incoming and outgoing air, or air movement, and will be able to maintain ideal temperature and humidity levels year-round.

In the winter, a properly vented roof allows outside cold air to enter and replace warmer air, which rises with convection. This serves to keep your attic cold, and a cold attic is exactly what you want, especially in the event of an ice or snowstorm. When snow and ice melt too quickly, ice dams can form and cause damage to your roof and gutters. A slower melt-off helps prevent this from happening. A warm attic in winter is also more likely to become too humid and is at risk for moisture buildup and mold. Keeping air on the move prevents condensation on the cold plywood roof deck, which can lead to mold growth. 

During summer a well-vented roof helps regulate temperature by allowing hot air to flow out of the attic. As hot air rises, it escapes through the upper vents at the top. This continual flow of air is critical to preventing moisture build-up and condensation within your attic. Moisture in your attic will lead to other problems like mold and can shorten the lifespan of your roof, as well as damage your home’s main structure. 

Saves Energy and Money

Proper roof ventilation will also help you save energy and money. Improperly vented attics will result in excessive heat build-up during the hotter summer months, causing your air conditioner to work harder to keep your home cool. Excessive attic heat can also cause roof shingles to age at a faster rate. It can also cause the plywood decking of your roof to delaminate because the glue can’t keep up with the expansion 

Wasted energy, condensation, mold, ice dams, rotting roof decks, aging shingles, and a shortened roof-life all add up to expensive problems that proper roof and attic ventilation can help prevent.

types of ventsTypes of Vents and Their Purpose

Both upper roof vents and lower vents along the soffits are necessary to create the right balance and exchange of incoming and outgoing airflow. 

Roof vents allow rising hot air and moisture to escape from the attic, preventing heat build-up and condensation, 

roof vents

depending on the season. There are two types of roof vents: ridge vents and box vents. A ridge vent is an air exhaust vent installed on the peak of a roof. A box vent is a hole cut into the roof with a box cover, and while positioned high on the roof, box vents are typically placed near the ridge or peak.

Soffit venting allows cooler, fresh air, to flow into the attic at the lowest points. The soffit is the part of your roof overhang that meets your siding. Together with roof vents, soffit vents 

soffit venting

create a passive system that effectively enables air to flow into, up, and out of the attic.

There are two types of soffit vents: rectangular and continuous. Rectangular vents are cut into the blocking between the rafters of your home. With continuous venting, the soffit is vented all the way around the attic area. This type of venting is for closed soffits where the rafters are not visible. 

Pro tip: Always keep all of your roof and attic vents open and un-impeded by debris to maintain proper airflow. 

How do I know if my roof is properly vented?

Every roof needs both roof and soffit vents. Simply walking around your house and looking at your roof and eaves will tell you if you have vents, but this alone does not mean you have sufficient ventilation. Inspecting your attic for signs of moisture is a more reliable way to determine if you have adequate venting. Any moisture on the tips of nails is the first sign. You can also touch your ceiling just below your attic on a warm sunny day. If it feels hot, your attic may be overheating. If it is winter, you might grab a flashlight and inspect your attic for condensation. Excessive heat and moisture are signs your roof and attic are not properly vented.

Of course, the best way to tell if your roof’s ventilation system is adequate is to have a professional inspection. This is a service we offer at Pacific West Roofing. Our experienced inspectors will give you an honest assessment of your roof, attic, and vents, so you can have peace of mind knowing your roof is in good shape and sufficiently ventilated, or be alerted to any problems that should be addressed before they become costly repairs. Contact us today to schedule an inspection.

Portland Roofing Services - Pacific West Roofing
Homeowners Maintenance Residential Roof Repair

8 Symptoms of Bad Gutters | Pacific West Roofing

Pacific Northwest winters don’t usually consist of heavy snow, but instead, heavy rain. This means that the gutters of your home are on active duty for days and months at a time. Many inches of rain and occasional ice storms can be hard on your gutters, especially if they are old or need repair. Gutters protect your home from water damage, which can translate to issues with insulation, temperature regulation, or mold growth. Check your gutters on a regular basis, and if you aren’t sure if you have bad gutters, keep an eye out for some of the signs listed here.


The average lifespan of gutters is between 15 and 20 years. If they haven’t been replaced in that time, then they should be checked by a professional to see if they are working at their peak. Even if they look fine, they might not be. Making sure that you have quality gutters will save you money in the long run.


If you see noticeable cracks or the beginning of rust on the gutters, it is time to consider replacing them. Rust and cracks lead to leaks, which can lead to damage and costly repairs later down the road.


Do your gutters look uneven or look like they’re sagging? This can be a sign that the system needs to be repaired or replaced professionally. Gutters that sag or slouch mean that they won’t work efficiently and could clog or leak.


If you see a lot of standing water near the downspouts, this could lead to a serious problem. When water pools near the bottom of your home’s exterior it can easily work its way down to your foundation. Having water underneath your home can lead to mold, rot, and expensive structural problems. If you see pooled water anywhere within a few feet of your home, call a professional to have your foundation, crawl space, and gutter system checked out. All you may need is an extension to your downspout that leads water further away from your home.


Northwest rain and wind storms can blow twigs, leaves, and other debris into the gutters. Clogs can be prevented by installing gutter guards, but if you are dealing with clogged gutters all the time, there may be an issue with the actual gutter that is causing the clog. If left to persist, overflowing gutters can lead to the pooling water problems mentioned above.


This is pretty common sense, but if a part of your gutter system is hanging off the side of your home, it’s likely broken and needs repair or replacement. Make sure that your gutters are installed well so they don’t fall off during the next rain, wind, or snow storm.


If you see any water damage where exterior walls meet your ceiling, you may have a gutter leak instead of a roof leak. Check your gutters in that spot for a crack, clog, detachment, or poorly sealed seam.


Have you noticed changes in your home’s siding? Is the paint peeling, chipping or rotting? This could be the result of ineffective gutters. Water could be leaking through or overflowing and splashing up against the house, and without the sealing power of paint, wood siding is quick to rot. Have your gutter system repaired or replaced now to prevent the need for bigger exterior projects.

If it’s time to do something about bad gutters, contact Pacific West Roofing for a free estimate. Call us at 503-635-8706 today.



Portland Roofing Contractor Since 1980!

CCB# 169414