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Water Damage: Basement, Attic, & Crawl Space Concerns

Thursday, April 23rd, 2020
water damage

While water damage is unwelcome anywhere it occurs in a house, the causes and effects often differ according to where it happens. While water tends to spread rapidly inside a house, certain parts of a home are simply more likely to be the origin, either due to the orientation of a particular space or the presence of certain contributing factors. Here are three specific areas often impacted by damage from water, as well as what’s typically involved in recovery:


Because water tends to flow downward to the lowest point, a home’s basement is typically ground zero for damage. Other factors include ruptured plumbing supply lines routed through the basement, sewage backups, and groundwater seepage through cracks in the foundation or basement walls.

A flooded basement holds water effectively and must usually be pumped out, then dried using high-volume ventilation. Mold remediation techniques are also required to inhibit contamination. Installation of a sump pump is advisable to prevent future flooding. Caution: due to electrocution hazard, never wade into a flooded basement. Contact an electrician to shut off all power first.


Usually the result of a leaky roof, attic damage from water may proceed unnoticed for some time. Ceiling stains and/or dripping into rooms below are often the first indication.

The saturated ceiling drywall must be replaced. Wet fiberglass attic insulation must usually be removed for drying, then treated to prevent mold. Saturated cellulose insulation cannot be effectively dried and must be replaced. Water in an attic may also infiltrate HVAC ductwork routed there, triggering mold contamination inside ducts.

Crawl Space

Water damage affecting a crawl space typically originates from heavy rain outdoors or a ruptured indoor pipe. A crawl space may remain wet due to a lack of ventilation and evaporation. This promotes mold growth as well as deterioration of wooden structures, including the subfloor. Moisture also creates a habitat for pests and vermin.

Outdoor water intrusion into a crawl space requires sealing entry points to keep out flooding. Grading the surrounding landscape to divert water is also helpful. Keeping a chronically wet crawl space dry may also require continuous fan ventilation.

Is Your Attic Protected From Water Damage?

Tuesday, September 17th, 2019
Attic water damage

Like the crawl space beneath your home, your overhead attic is a frequent focal point for water damage. Because attics are infrequently visited by occupants of the house, water damage often progresses unseen for a good amount of time. By the time it’s noted, damage from situations like these may be well advanced:

  • Rotted wooden attic structure including rafters, joists and subroof
  • Saturated attic insulation
  • Toxic mold contamination
  • Ceiling deterioration
  • Water intrusion into living spaces below

Damage to attics may result from four water-related causes which in turn call for different remedies:

Roof leaks during rain. Pinpointing roof leaks requires both exterior and interior inspections. Signs of roof leakage into the attic include darkened spots or streaks on the underside of the plywood subroof. However, these interior signs often result from an exterior leak that may be far from the point where water actually drips into the attic. Therefore, locating and repairing roof leaks affecting the attic is generally a job for a qualified roofing contractor.

Leaky plumbing routed through the attic. Any leakage from water supply lines is unacceptable, including tiny pinhole leaks and minor seepage. In addition to providing a continuous source of attic moisture, leakage generally indicates deterioration inside pipes which may result in a sudden pipe rupture that inflicts severe damage to living spaces below. Leaking pipes require immediate attention by a professional plumber.

Continuous high humidity. When attic ventilation is inadequate, extremely hot, humid air accumulates in the enclosed space during daylight hours. As the attic cools after dark, condensation forms, drenching wooden structure, degrading insulation and feeding mold. To break this continuous cycle, make sure all attic vents are open and unobstructed by insulation or other objects. If passive attic ventilation is insufficient to moderate attic temperatures and exhaust humidity, consider installing powered attic vent fans.

Exposed HVAC ductwork. When humid attic air contacts cold ductwork conveying air from the central A/C, condensation soaks the area around the ducts, saturating insulation and triggering mold growth. All ductwork routed through attics should be insulated to prevent condensation as well as inhibit thermal gain or loss.  

3 Hidden Places Mold Spores Can Thrive In Your Home

Thursday, April 25th, 2019

A typical individual mold spore is as small as 3 microns. By comparison, a human hair is over 100 microns wide. Mold is ubiquitous in nature and dormant mold spores pervade the environment, both outdoors and indoors. Once specific conditions of moisture, temperature and food supply are met, dormant spores can quickly become active and start to multiply. Live reproductive spores are released into indoor air, spreading contamination. Inhaling these living spores is a known cause of allergic reactions and even chronic illness in certain individuals.  

Here are three hidden locations where conditions are favorable for mold growth inside your house:

Down in the Basement

Damp basements are common due to lack of ventilation. Persistent dampness provides moisture for growing mold. Also, since household plumbing is often routed through the basement, small leaks and condensation on pipes contribute to the dampness. Mold dislikes natural sunlight and grows best in cool temperatures, so a darkened basement is a preferred location. The pungent musty odor often associated with basements is usually a giveaway that mold is growing there.

Up in the Attic

Mold spores lying dormant in a dark attic are waiting to be activated by contact with water. In enclosed attics, humidity often accumulates to high levels, providing sufficient water vapor to activate dormant spores. These spores grow well in porous material such as beds of insulation.  Minor roof leaks which may not be evident in living spaces below are another water source in the attic. Insulation material itself doesn’t provide mold food. However, the dust that accumulates within insulation fibers often contains nourishment and the paper backing attached to roll-out insulation batts provides cellulose, as well.

Inside the HVAC System

The condensate drip pan beneath the indoor air handler diverts condensation from the A/C evaporator coil into a household drain. If the pan drains sluggishly due to a clog, however, the continuous presence of warm stagnant water in the pan provides a perfect environment for mold. Spores pulled through the system airflow infect the water. Active mold growth may thrive in the drip pan and/or the system evaporator coil above.

Should You Really Be Concerned About Attic Mold?

Tuesday, November 20th, 2018

attic moldAttic mold is relatively common simply because attics provide very favorable conditions for mold to grow. Dampness from high humidity is a major mold trigger as water vapor from living spaces below migrates upward, accumulating in the enclosed attic. In many climates, an attic also provides very favorable warm temperature ranges that support active mold growth.

But should mold growing far away in the attic concern residents in the rooms down below? The answer is a resounding yes, because mold growing up in the attic typically doesn’t stay up in the attic. Microscopic airborne mold spores released by growing mold migrate into living spaces below. This not only causes allergic reactions and illness in susceptible persons, it also can grow and spread into the inhabited parts of the home. Two factors affect mold movement:

  • Studies have shown that airborne spores from active mold growth can seep out of enclosed spaces constructed with average residential methods. Unless the area is built and sealed to very high standards not common in residential construction, tiny openings in the structure will allow spores to migrate.
  • Contaminated air may be pulled out of a moldy attic down into living spaces due to pressure differentials. Colder air-conditioned air is heavier and naturally sinks to lower levels inside an enclosed house. This downward air motion creates a very subtle suction effect that draws spore-contaminated air out of the attic through tiny structural cracks and gaps into the living areas below.

To reduce potential ill effects as well as structural damage from attic mold:

  • Ventilate the attic to reduce accumulation of water vapor rising up from rooms below.
  • Eliminate other attic moisture sources such as roof leaks and condensation dripping from HVAC ducts.
  • Locate and seal even the smallest openings in the ceiling which allow air movement that conveys mold spores down into living spaces.

Attics typically include unfinished structural wood that provides desirable growing surfaces for mold which will penetrate the porous material. Where presence of attic mold is confirmed by inspection and testing, professional mold remediation techniques to neutralize and remove all mold must be utilized.

3 Tips to Prevent Leaks Due to Freezing Attic Pipes

Tuesday, October 23rd, 2018

foam water pipe insulationBecause water always flows downward, freezing attic pipes that rupture are especially damaging to the living spaces below. In many areas of the country where homes are built on a slab foundation, water supply lines are routinely routed through the attic space. Because most attics are unconditioned, a hard freeze that plunges attic temperatures into the mid-20s for any length of time can cause a burst pipe.

A ¼-inch split in a water line caused by freezing can potentially unleash 600 gallons of water per hour when the pipe thaws. The torrent will quickly permeate through openings in ceilings and soak rooms below. Water will also cascade into the interior of wall cavities and flood deep into the structure.

To avoid drastic consequences—expensive water damage and inevitable mold contamination—here are three tips to prevent freezing attic pipes.

  • Insulate exposed pipe. Wherever water supply lines pass through the attic, foam pipe insulation sleeves should be installed on all exposed spans. Simply laying batts of existing fiberglass insulation over the pipes or burying the pipes in loose-fill cellulose insulation is not sufficient. Use foam pipe insulation specifically designed for the purpose. Also make sure all sections of the pipe are insulated–custom cut and form insulation pieces to cover rounded elbows, t-joints and other irregular spans.
  • Use heat tape on problem pipes. If a span of pipe is particularly vulnerable to low temperatures, electric pipe heating tape acts like an electric blanket for pipes to prevent freezing. Controlled by a thermostat to activate only when the attic temperature plunges dangerously low, the tape typically consumes about 5 watts per foot. Therefore, a six-foot span of “problem pipe” would only use about 30 watts when activated in cold temperatures. Because of potential hazards, pipe heat tape must be installed by a professional plumber or electrician only.
  • Consider PEX pipe. PEX is flexible cross-linked polyethylene now commonly installed as household water supply lines instead of rigid copper. Though PEX is not entirely resistant to damage if extremely frigid temperatures strike, its flexibility makes it more freeze-tolerant and less likely to rupture during “normal” winter weather.

How to Track Down the Source of Ceiling Water Damage

Thursday, August 2nd, 2018

ceiling water damageOne thing about ceiling water damage: it’s hard to miss. Once it appears, it’s the very first thing you’ll notice every time you walk into the room from then on.

Most ceilings are composed of gypsum wallboard that discolors as water soaks in. In addition to causing conspicuous stains, water absorption also compromises the structural integrity of gypsum and poses a real risk that some part of the ceiling may eventually fall in. Whether large or small, ceiling water damage is an issue that needs to be tracked back to its source and resolved. Here are some possible causes:

Roof Leaks

When the affected ceiling is in a room below the attic, rain water penetrating the roof may be dripping down on the attic side of the ceiling. In addition to threatening the solidity of the ceiling, ongoing roof leaks also ruin attic insulation and trigger mold growth. Because water may drip onto the ceiling some distance away from the point where it actually penetrates the shingles and sub-roof, a professional roof inspection is required to pinpoint the location of the leak.

Bathroom Problems

If the ceiling issue is on a lower floor beneath an upstairs bathroom, the possibilities are obvious. A water supply pipe inside a bathroom wall may be covertly dripping. Leaks can also result from a defective wax seal around the toilet. A particularly troublesome source is the drain pan sealed underneath the shower stall. Leaks in the not-easily-accessible pan manifest as a conspicuous ceiling stain in the room below. Leaks from plumbing inside walls or a defective drain pan under the shower stall should be diagnosed and repaired by a qualified plumber.

Attic Issues

Hot, humid air accumulating in the attic during summer may trigger chronic condensation on cold air conditioning ducts routed there. It can saturate attic insulation and damage the ceiling below. Wrapping air duct insulation around the ductwork prevents contact with humid air and resultant condensation. Also, bathroom or kitchen exhaust fan ducts in the attic that are leaky or disconnected may continuously discharge warm, moist air onto the ceiling that triggers deterioration.


Can Water-Damaged Insulation Be Salvaged?

Tuesday, July 3rd, 2018

wet insulationInsulation in the attic is often the first victim when roof leaks occur or when plumbing pipes routed through the attic leak. The two most common types of insulation — fiberglass batts and blown-in cellulose loose-fill—are vulnerable to attic water damage in two specific ways:

Loss of insulating value. Wet insulation no longer performs its primary function of inhibiting heat transfer. Saturated insulation typically loses at least 40% of its insulating R-value. While fiberglass is technically waterproof, inside an enclosed attic the thick batt retains moisture which degrades its thermal resistance properties. Cellulose loose-fill, made of pulverized particles of paper and cloth, absorbs a large volume of water and compacts, losing the fluffy characteristics that make it an effective insulator.

Mold growth. Fiberglass insulation traps dust, which typically contains microscopic airborne mold spores. Following exposure to moisture from attic leaks, active mold growth affecting the paper backing of fiberglass batts is common. Cellulose insulation is treated with chemical fire-retardants that also make the material itself fairly mold-resistant. However, the absorbency of cellulose means destructive mold is still a major factor if it becomes wet. Saturated cellulose insulation acts like a wet sponge that continuously transfers moisture to adjacent wooden structure in the attic and to the ceiling drywall below, causing mold growth and destructive decay in these materials.

Can Wet Insulation Be Saved?

  • Fiberglass batts will eventually dry if lifted up and exposed to warmth and sustained air circulation. However, if active mold growth is evident, the material should be removed. Drying a large area of soaked insulation as well as detecting mold is a labor-intensive process. Because fiberglass batts are relatively low-cost, instead of attempting to salvage wet, possibly contaminated material the better option may be removal and replacement with new insulation.
  • Soaked cellulose insulation will retain absorbed water for an extended time and resists drying. During that time, it will also degrade wooden structure and trigger attic mold growth. Wet cellulose is generally not salvageable and needs to be removed, then new material blown-in to replace it.


Prevent Attic Mold With These Simple Tips

Tuesday, June 12th, 2018

attic moldWhat is it about an attic that’s so attractive to mold? Just about everything that makes it a place people tend to avoid. Most attics are dark, warm, overly humid, stuffy, and dusty. In other words, the perfect accommodation for mold. Mold growth can be destructive to vital wooden structure in the attic and also ruin attic insulation. Moreover, microscopic airborne mold spores migrate down into living spaces and spread contamination further throughout the home.

Once active mold growth has established a foothold anywhere, including the attic, professional mold remediation services are required to effectively neutralize and remove it. However, there are several preventive steps you can take to make your attic less mold-friendly now.

Maximize Ventilation

Old houses seldom had moldy attics. Imprecise construction methods standard in those days made attics very drafty. Constant air exchange with the outdoors kept attic humidity low and mold growth seldom had a chance to get started.

Make sure existing attic air vents at the soffits and the roof peak are unobstructed and wide open to promote continuous passive air flow. For a more active approach, consider installing turbine vents on the roof that pull moist air up and out of the attic every time a breeze blows, or a solar-powered electric roof vent fan.

Dry It Out

Make sure that bathroom vent fans, kitchen vent fans and dryer vents aren’t exhausting directly into the attic space. They should all be connected to vent pipes that extend all the way to the outdoors. Also, make sure that vent pipes routed through the attic are intact, joints and connections are secure and not leaking vented air.

Check ceilings in bathrooms, kitchen and other humid spaces for cracks, gaps around light fixtures and other openings that could allow warm, moist air to infiltrate the attic.

During rain, look for dripping and other signs of roof leakage into the attic. Repair requires a roofing professional as drips often appear far from the actual leak.

4 Tips For Preventing Attic Water Damage

Tuesday, May 1st, 2018

attic water damageAttic water damage has several potential causes. It usually has multiple consequences, as well. A single incident of attic water damage may necessitate any or all of the following: roof repair, replacement of attic beams, removal of ruined insulation, repair of damaged sheetrock in ceilings below, replacement of carpet or other interior items affected by water, and mold remediation to remove toxic contamination inside the attic.

Prevention tips

Attic water damage can originate from above, below, or from sources inside the attic itself. Here are four tips to prevent it:

  1. Inspect the roof. Rain water seeps behind split shingles or through leaky flashing. Dripping inside the attic may occur some distance from the actual roof leak however, as water travels along the sub-roof panels and/or attic beams. Dark streaks on the underside of the sub-roof are one indicator of ongoing leakage.
  2. Prevent ruptured pipes. Water supply lines are often routed through the attic. In unconditioned attics, frigid winter temperatures can rupture pipes. Insulate all exposed attic pipes to prevent freezing. Inspect for evidence of pinhole leaks as well as seepage around joints. Refer any signs of leakage to a qualified plumber.
  3. Control condensation. Water vapor chronically infiltrating from living spaces below accumulates in the attic. Make sure soffit vents and roof vents are unobstructed to optimize passive air circulation. If condensation issues persist, consider adding a powered vent fan at the roof peak. To reduce infiltrating water vapor, seal air leaks in ceilings, around recessed lights and weatherstrip the attic access hatch/door.
  4. Maintain attic appliances. In some homes, the water heater is installed in the attic. Flushing the water heater tank regularly per manufacturer’s instructions reduces chances of attic water damage due to tank corrosion and leakage. Where the central A/C air handler is mounted in the attic, a clogged condensate drain line may trigger an overflow. An overflow safety switch can be installed to automatically shut down the unit before water damage occurs.

Taking time to inspect your attic periodically and do some routine maintenance can prevent a costly repair bill later.