Serving Salt Lake City, UT & Nearby Areas
(385) 438-3591
Serving Salt Lake City, UT & Nearby Areas
(385) 438-3591
Because it probably is not a leak. Warm, moist air rises out of your house, hits the cold underside of the roof deck, and condenses there. The water forms inside the attic instead of coming in from outside. On a cold dry morning, every nail can be dripping.
Check the attic on a cold morning to see whether water is forming on the deck rather than running in.
Condensation appears evenly across the underside and at nail points, while a real leak follows one path.
Go up with a flashlight on a cold morning and look at the nail tips.
In a Utah winter your roof can drip on a dry day. That's because the water is not coming in from the storm, it is coming up out of your house.
Mattie Tueller, Master Roofing
From inside your house. Showers, cooking, laundry. Simply breathing put moisture into the air, that warm moist air rises. It finds its way into the attic through gaps in the ceiling. Up there it meets a roof deck that is as cold as the outdoor air. The moisture condenses out onto the wood.
Nail points are the coldest spots in the assembly. Each shank runs through the deck to the outside air. So it conducts cold straight into the attic and condensation collects there first. A homeowner looking up sees water hanging off dozens of nail tips at once and reasonably concludes the roof is full of holes.
A roof full of holes does not behave that way. Holes leak in one place, when it rains. This happens everywhere at once, on a clear cold morning. It stops when the day warms up. That pattern alone rules out most genuine leaks before anybody climbs anything.
Look at the pattern and the timing. Condensation shows up evenly across the underside of the deck, worst on cold mornings. It does not correlate with rain. A real leak concentrates in one area, traces back to a specific failure like a flashing or a boot. Shows up when water is on the roof.
The two can also coexist. A house with heavy condensation can have a real leak hiding inside it. Diagnosing a genuine leak is a different job, covered in how to figure out why your roof is leaking.
Because the moisture is not coming from the weather. Utah is one of the driest states in the country. That says nothing about the humidity inside a sealed, heated house in January. A family generates a surprising amount of water vapor daily, and in winter that air has nowhere to go but up.
Cold air holds very little moisture. So the temperature difference between your living space and the roof deck is at its most extreme exactly when the house is closed up tight. That combination, moist indoor air and a deck at outdoor temperature, is what produces condensation.
It surprises people who expect this to be a Gulf Coast problem. Master Roofing finds it in roughly 90 of every 100 attics here. That's why the dry-climate assumption is worth setting aside. The outdoor humidity you feel on your skin in January has very little to do with the air sitting above your ceiling.
Moving the moist air out and keeping it from getting up there. That means balanced ventilation so the attic exchanges air with outside. Air sealing at the ceiling so less humid air escapes upward in the first place. Neither one is a roof repair, which is why patching shingles never solves it.
None of this requires tearing off the roof. Most of it is a single visit once someone has measured what the attic actually has. Left alone, persistent condensation rots decking and grows mold on the underside of the roof. What that does to the house is covered in whether your roof can cause mold even though Utah is dry.
This is one of the calls Master Roofing gets every Utah winter. It usually starts the same way: it has not rained in weeks and my roof is leaking. People are really rattled by it. That's because a roof leaking on a dry day feels like something is badly wrong with the house.
Almost always it is condensation, and almost always the roof itself is fine. The house is doing what houses do in a cold dry climate. The attic has no way to get rid of the moisture it is being handed.
What I want a homeowner to take from this is that the diagnosis changes who you should call and what it should cost. A roofer patching shingles will not fix it. Paying for that is money spent on the wrong problem. In a Utah winter your roof can drip on a dry day. That's because the water is not coming in from the storm, it is coming up out of your house. Get someone in the attic on a cold morning to confirm which one you have, before anyone sells you a repair.
This article is general information about Utah roofs, not an assessment of yours. Every roof is different, and no article can tell you what is actually happening on your specific house. Have a licensed roofing contractor look at it in person before you act on anything here.
Left alone it becomes structural. Repeated wetting rots roof decking from the top side down. Badly rotted sheathing will not reliably hold a nail or a person's weight. It also supports mold growth across the underside of the roof. A single damp winter is not a crisis. But several winters of it turns a ventilation fix into a decking replacement.
It reduces the supply of moisture, which helps a little. But it does not address why humid air is reaching the attic or why the attic cannot flush it. Most homes solve this far more cheaply by sealing the ceiling leaks and correcting the ventilation. Treat a dehumidifier as a comfort appliance rather than as a fix for what is happening above your ceiling.
Frost is condensation that froze before it could run. It means the same thing: moist indoor air is reaching a very cold deck. It often alarms people more than dripping does, but the cause is identical. The real problem arrives during the thaw, when all of that frost melts at once and soaks the decking and the insulation below it.
Not by itself, and it can make things worse if the insulation buries the intake vents at the eaves. Insulation slows heat moving upward, which is useful. But the moisture still needs a way out of the attic. Sealing air leaks at the ceiling helps more than depth does. The ventilation has to keep working underneath whatever gets added.
Start with a roofer. That's because ventilation is part of the roof assembly and a roofing company can tell you whether the attic meets the required ratio. They can also confirm whether you have condensation or a genuine leak. That's the question that decides everything else. Air sealing and insulation work can follow once you know what you are dealing with.
We're here to see what's going on with your roof. A real assessment starts with your history and your attic, not a number from the driveway. You'll get a straight answer about what's up there, what it needs, and what it costs. Sometimes the honest answer is: your roof looks great.