A turbine vent leaking is usually telling you one of three things: the head has stopped spinning, it has been knocked out of plumb, or the flashing at its base has failed. Turbines, often called whirlybirds, keep rain out mainly by spinning, so once they seize or tilt, water can blow straight in. Most leaks are fixable, but some roofs are better off with a different vent.
Water dripping near a turbine in your attic? Call Cannon Roofing at (940) 627-1045, day or night, or book a visit on our contact page.
How a turbine vent keeps water out
A turbine sits on a round base, or throat, over a hole in the roof deck. Wind spins the curved fins, and the spinning head pulls hot air out of the attic. While it turns, the motion flings rain away from the gaps between the fins. The base is flashed into the shingles like any other roof penetration, with shingles lapped over the upper flange and the lower flange lying on top of the shingles below.
That design works when every part is in good shape. Each failure below breaks one piece of it.
Why your turbine vent is leaking
A turbine vent leaking in one storm but not the next is a strong hint about which of these is to blame.
Seized or worn bearings
Turbines spin on bearings that eventually wear, rust or dry out. A seized head sits still with its fins open to the weather, so wind-driven rain goes right through. Squealing or grinding before it stops is a common warning. A head that only turns in strong gusts is on its way to seizing.
A bent or tilted head
Hail, high winds, tree limbs and foot traffic can bend fins or knock the head off plumb. A tilted head wobbles, rubs, stops spinning and exposes a gap at the collar where the head meets the base. Crushed fins can also funnel water inward.
Failed base flashing
This is the most common source. The flange can crack, rust through or be installed with the upper edge on top of the shingles instead of tucked under them. Nails through the exposed flange loosen, and sealant around the base dries and splits in the Texas sun. Water then runs under the flange rather than over it.
Loose or separated parts
Turbine heads sit on adjustable bases. Screws holding the head to the base can back out, and in high winds the head can pull partly or entirely off, leaving an open hole in the roof.
Quick ground-level checks
On a breezy day, see whether every turbine is spinning. Look for one that leans, wobbles or has dented fins. In the attic, check for water stains on the deck around the vent throat, rust on the base and damp insulation below. Stains that spread out from the base point to flashing; drips directly beneath the opening point to the head.
Repair or replace the turbine?
When a repair is enough
If the base flashing is sound and the head is simply stiff, loose or slightly out of plumb, a roofer can re-secure it, straighten it or replace the head alone. If only the flashing has failed, the base can be reset with shingles lapped correctly around it and fresh fasteners. Our roof repair crews handle both.
When a new turbine makes sense
Rusted-through bases, badly bent heads or turbines that have seized more than once are candidates for replacement with a new unit, installed and flashed as one assembly.
When a different vent type is the better answer
Sometimes the problem is the ventilation plan, not the turbine. A roof with turbines plus a ridge vent or powered fan can short-circuit airflow. During a reroof, many homeowners choose to remove turbines, patch the openings and switch to a single exhaust type such as a ridge vent, sized against the soffit intake. Our comparison of ridge, box, turbine and solar vents shows how each performs.
Whatever the choice, the key is keeping enough exhaust. Removing turbines without replacing that exhaust capacity leaves a hotter attic and faster shingle aging.
Getting a turbine vent leak fixed by Cannon Roofing
We start by checking every penetration near the stain, since pipe boots and flashing close to a turbine can be mistaken for it. We test whether the head spins freely, check it for plumb, inspect the flashing and look at the whole ventilation layout before recommending a fix. You'll get photos and options, and we offer a free inspection and estimate.
Cannon Roofing has been based in Decatur since 1994. Every technician has earned the Technician Seal of Safety, meaning each is background checked, drug tested, factory trained and insured, and our emergency line is open 24/7 if a turbine blows off in a storm.
What to do if a turbine blows off
- Stay off the roof, especially if it's wet or the wind is still blowing.
- Put a bucket and plastic sheeting under the opening in the attic if you can reach it safely.
- Photograph the missing head and any debris in the yard for your records.
- Call a roofer to cover the opening; an open vent hole lets in a lot of water in one storm.
Frequently asked questions
Can I oil a turbine vent to stop it squeaking?
Some models allow light lubrication, but many sealed bearings don't. Squeaking means the bearing is wearing. Treat it as an early warning and have the vent checked before it seizes.
Should turbines be covered in winter?
Covers are sometimes used in colder climates, but in North Texas they're rarely needed and can trap moisture in the attic. A turbine that leaks in winter storms more likely has a flashing or bearing problem.
How many turbines should my roof have?
That depends on attic size, intake venting and other exhaust on the roof. A roofer can calculate the ventilation the attic needs and recommend how many vents, of which type, will meet it.
Want the leak around your whirlybird stopped for good? Call Cannon Roofing at (940) 627-1045, any hour, and we'll inspect the turbine, flashing and attic, then explain whether to repair, replace or rethink your vents. Or write to us through our contact page.