Roof Underlayment and Ice and Water Shield in Chester UT
- Jul 16
- 6 min read
A customer called us in response to a small brown stain on the corner of an upstairs
bedroom. It was slow flowing and there wasn't a noticeable rush of water to suggest an imminent flood.
The discoloration only became apparent after several days of snow melt
From our view on the ground, the roof shingles above the room were intact. There were
no missing shingles in the yard and no vent opening that would let water flow
unimpeded to the eaves. It appears as if the roofing layer beneath the shingles had an
issue.
That's when it's helpful to have roof underlayment and ice and water shield.
Chester homeowners considering a roof replacement or repair typically discuss shingles
and other visible aspects of a roofing system. The importance of what goes beneath the
roof's surface is often overlooked until a leak develops.
What Is Under the Shingles?
Roof underlayment is a protective layer that goes over the roof deck but below the
shingles or metal roofing. Its primary function is to ensure the roof's upper layer resists
the elements, and any moisture that makes its way beneath the shingles is kept away from the roof deck.
There are many potential trouble spots on a roof. Valleys, vents, chimneys, and
intersections with siding or skylights all require special attention. Time and the weather
can contribute to deterioration at these points, leaving the roof more susceptible to
damage.
A shingle could lift and then fall back, flashing might loosen sufficiently to allow a small
space for water to get through, or a vent boot on the roof could crack when it's hard to
see.
The underlayment provides some protection should these issues develop.
It doesn't eliminate the need to address the roofing material or other components, as
water will eventually find its way through a compromised roof. However, the extra layer
can give much-needed time to examine the situation.
Ice and Water Shield Is Different
Ice and water shield is a heavier grade of waterproof membrane that is often used on
roofs. Roofers typically use it to cover problem areas on the roof deck where moisture
tends to collect or flow.
These can include the eaves, valleys, skylights, chimneys, plumbing vents, low areas on
the roof deck, and intersections with siding or wall sections
Each of these is a potential weak point on a roof. The valleys tend to hold runoff from
both sides of the roof, snow can accumulate around chimneys, water flows more slowly
down low spots, and the eave area can freeze up while the rest of the roof thaws.
Why Chester Winters Put These Layers to Work
A roof in Chester UT has to deal with more than just snowfall. Sunshine following a few days of cold weather can cause the snow on the roof to melt. However, temperatures typically dip back down during the night causing some of that meltwater to freeze.
The same cycle can occur a few times throughout the winter before an ice dam builds
up along the eaves.
More snow falls and melts but can't flow down over the frozen edge, so it backs up and
runs down behind it. This can cause water to make its way underneath the roofing
materials and into the house.
Roofing systems are designed to shed water running down the roof, but water trying to
flow up and over the eaves presents a problem.
Ice and water shield membrane could help prevent further damage should an ice dam
develop.
Sometimes the Roof Is Not the Whole Problem
We've seen customers replace shingles along the edge of a roof with suspected ice
dams only to have the same issue appear the next winter.
The cause could be in the attic. Warmed air from the house could escape through
opening around the attic hatch, electrical outlets, or plumbing. This would raise
temperatures in the attic, allowing snow to melt on parts of the roof deck before flowing
down and freezing at the colder eaves.
In this scenario, ice dams are more of a symptom of the problem rather than the cause.
Adding membrane to the roof would help protect the roof deck from the damaging
effects of water, but tacking on more insulation, sealing some areas, or improving attic
ventilation would also be beneficial.
This is why we look at the entire roofing system, not just the shingles. While the top layer
plays an important part in keeping water out, the deck, flashing, and other elements in
combination with attic conditions all contribute to proper roofing.
The Spots We Usually Check First
If a customer is concerned that their roof is leaking when it's snowing outside, we don't
immediately jump to the conclusion that the entire roof is compromised. We ask them to
provide details about the leak: where it was located, when it appeared, and what was
above it.
Valleys are one location to investigate because they tend to hold water or ice that runs
off the roof. Debris or snowpack can build up in these areas, causing the water to slow
down and potentially work its way into the roof structure if there are any weak spots
beneath the shingles.
Chimneys are another possible trouble spot and usually have flashing on multiple sides
that all need to be examined. One area could be compromised even if the others appear
intact allowing water to run down along the roof deck.
Skylights can act similarly to chimneys in some ways. The flashing around them could
have a weakness allowing water to track down and under the roof covering.
Plumbing vent boots are another potential weak spot that many homeowners overlook.
The rubber membrane around the vent can crack as it's exposed to temperature
changes and UV light. Water can then get through the small opening and onto the roof
deck.
What Can You Check Without Climbing Up
You don't need to be up on the roof to check for early signs of trouble. In fact, it's best to
avoid climbing on the roof during the winter anyway. Start inside the house and take note
of any strange smells, damp spots, or peeling paint near the ceiling or walls.
A small stain on a ceiling near an outside wall is worth noting, especially if it appears after
a thawing period following a snowstorm. The same goes for dampness around a
chimney or a musty odor upstairs.
The attic can also give some insight. Look out for wet insulation, darkened or warped
wood, frost on the roof decking, rust spots on nails, or water streaks running across the
floor. Water doesn't always come straight down through the roof, it can run alongside a
ceiling joist before dripping down somewhere lower.
The outside of the house can also provide some telltale signs of roof issues. Missing or
damaged shingles, compromised flashing, heavy ice along the edges, and granules in
the gutters are all worth investigation.
What Should a Roofing Estimate Explain?
A roofing estimate shouldn't just include the brand and color of the new shingles. You
should make sure you understand what type of underlayment is being used and where
the ice and water shield should be installed. The roofing company should give you specifics on the work around valleys, chimneys, vents, skylights, and the intersection with exterior walls.
Ask them if they'll reuse flashing and other elements or replace them with new ones. You
should also be informed on the options available should they find damaged roof decking
after removing the old roofing materials.
The cheapest roofing job can often hide work from view once the new shingles are in
place. An oversight such as the omission of a waterproofing layer isn't apparent from the
driveway, but it can cause roof issues for the next homeowner.
Repair or Replacement?
A roofing problem often doesn't require an entire replacement when the underlayment
is the main issue. If the roof has a few damaged spots such as in a valley or vent area or
one side of a chimney, a qualified roofer can remove the affected material and
underlying roof deck before installing new ones in its place.
It might make more sense to replace the roof when it's nearing the end of its lifespan,
there are signs of deterioration in several places, and the shingles and underlying
materials are failing together.
There's usually a point when it's more financially viable to invest in a total replacement
rather than several repair jobs.
The Hidden Part Still Counts
After a roof is installed or repaired, no one looks at the underlayment with pride. It plays a vital role in protecting the home from snow melt, wind blowing a shingle off the roof, or water finding its way around the chimney flashing.
For Chester homeowners, that means reliable de
cking, underlayment, ice and water
shield at problem spots, flashing, and healthy attic conditions can stop a minor winter
leak from becoming a major repair.
TJ Roofing serves the Chester area plus Ephraim, Gunnison, Manti, Mt. Pleasant, and the
surrounding Central Utah communities.
If you're trying to understand a roofing problem or planning a replacement, we can
inspect your entire roofing system and identify the issues and solutions. We offer roof
replacement, roof repairs, and emergency roofing services
Comments