Troubled Houses - The Home Owner's Resourcesm - Moisture Damage
We see many interesting adverse conditions during our inspections, partly because of the unlimited number of ways people can mess up a house, but also because we do a thorough inspection to reveal these adverse conditions. We hope these stories and illustrations help home owners avoid these costly conditions by learning about causes, preventions, and remedies. A home purchase can create opportunities for the new owner to improve the home, possibly increasing its value, durability, and usefulness.
NOTICE TO BUYERS & SELLERS: This site does NOT encourage or discourage the purchase of any individual house, or style, age, location, or condition of house. Conditions shown and/or described in the following articles may have been remedied at the house where these conditions were found. These conditions typically can be remedied by qualified contractors. The presence of these conditions in any house is comparable to any other real estate consideration such as price, size, or location. Consult a qualified home inspector before purchasing any house, and consult a qualified real estate agent for more information on how to handle a real estate transaction where adverse conditions are reported in a home inspection. This site does not describe any house by address or knowingly show a readily identifiable exterior image. Further, no home actively listed for sale on the Twin Cities MLS will be described on these pages at the time the article is posted.
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"Troubled Houses - The Home Owner's Resource" is a SERVICE MARK of Hankey & Brown Inspection Service Inc. Click here for the list of topics and all articles in this resource. Also see our Ice Dams page.
Moisture Damage Topics:
Water Woes - Flashing & Windows
Broken roof drain - Decayed deck frame
Chimney chase leak - Structural frame decay
Partial repairs - Wall damage below deck flashing
Crawl Space & Attic - Moisture movement in buildings
Contemporary Stucco house - Water intrusion
Complex Roof & Missing flashing - Following the moisture path
The Power of splashing water - Linking the clues
Loose dryer vent in attic - Is it still leaking
Water Intrusion in a 1990 built home
One Clogged gutter, one window, rain, & gravity, lead to extensive water damage
At first glance this 18 year old house looks normal. However, a closer look reveals some troubling details at the intersection of the vinyl siding and the brick veneer wainscoting.
The metal flashing is buckled between the windows and the siding and shutters are bowed. There are potential water entry points where the flashing meets the windows.
A six inch long probe inserted into a gap in the window seal met no resistance, indicating another potential water entry point in the wall. Based on the window and exterior conditions, an invasive investigation was recommended. A few days later, a forensic investigator made a cut in the wall and revealed that the leaks at the flashing and windows had led to extensive decay of the wall sheathing behind the brick.
The estimate to repair the wall including removal of the brick and replacement of 4 windows was $20,000. One week later, we found a similar condition beneath a bay window in a 16 year old house about 1 mile away.
A Broken Drain and a Deck over a crawl space: A bad mix
Sometimes a small detail is the first observed condition in an inspection that reveals significant adverse conditions. In this case, the first detail was an unusual location and pattern of moisture on a basement wall.
The damp area was centered below a 3" diameter pipe, sleeved with black foam insulation. No other areas of the basement wall were damp. An inspection of the flat roof help identify the pipe as one of the roof drains. There was a wood deck placed over a crawl space between the main house and an out building serving as a pool equipment room, bath house, and guest quarters. A wood hatch covered the access to the crawl space beneath the deck. The hatch was decayed and inspection of the crawl space revealed extensive water damage, rot, and even mushrooms growing on the decaying wood beams that supported the deck.
Further inspection of the crawl space revealed that the roof drain pipe had become disconnected just outside the basement wall and had been discharging roof runoff water into the crawl space for a very long time. The excess moisture led to decay in nearly all the wood components such that we recommended no use of the deck until a qualified contractor made all necessary structural corrections.
Leaky chimney chase -structural water damage
The chimney chase on the rear of this house had leaked for a long time causing significant water damage to the wood "I" joists supporting the floor and chimney. Our report recommended further investigation to determine the extent of damage and suitable repair methods. One exterior indication of the leak was a small mushroom growing on the chimney siding. Click here for moisture investigations.
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Beware of Partial Repairs in Foreclosed Houses
The stains and drip marks at the top jamb extension of this patio door were an important clue to discovering significant water damage (see photo below) in the frame over this door.
The waferboard was so damaged that it crumbed when probed with a finger tip. Damage from splash of roof runoff onto deck. See next photo below.
As shown in the photo, the slider door to the deck was recently replaced and a rain gutter was recently installed to control the water, but repairs below the deck where not done. The damage was hidden except for stains and drip marks on the top jamb of the lower door. Other water damage to the wall below the desk is possible but not determined in this inspection. Only two siding panels were opened for this inspection. Further invasive investigation was recommended. Click here to return to Moisture Damage topic list
Crawl Space & Attic = Critical Inspection Areas
A significant minority of Minnesota homes have underfloor crawl spaces. Access to crawl spaces and attics is usually inconvenient, so maintenance of the building and equipment in these areas is often neglected. Adverse conditions may develop in these areas and go unnoticed for a long time. These photos of one townhouse include a many adverse conditions that were unseen by the occupants.
At first glance the bare soil may not seem to be a concern, but elsewhere in the crawl space the soil was wet and there was moldy debris including discarded cardboard boxes. The importance of keeping soil moisture out of the house, by covering the soil with a plastic vapor barrier will be evident in other photos. Other sources of moisture in the crawl space included a improperly sloped and previously leaking main waste pipe.
The dryer vent was loose and discharging moisture and lint into the crawl space.
The furnace was located in the crawl space and its combustion vent was rusted out and leaking fumes (carbon monoxide, carbon dioxide, and water vapor) into the crawl space.
The vent rusted out due to a very poor installation of the furnace. The vent began at the right side of the furnace, made two 90 degree turns then was connected to an oversized vent that served the previous furnace. This vent configuration permitted the combustion fumes to cool before they reached the vertical section of the vent. The acidic moisture in the cooled fumes caused the vent to rust out.
The furnace installer also did not make a smooth transition in the return air duct when connecting to the existing ducts, and did not provide a filter cover.
This duct configuration and lack of filter cover helps pull damp air into the heating system. The dampness also rises through the house via unsealed wall cavities containing the plumbing system. The webs around the opening indicate the air flow.
The moist air reached the attic via this plumbing chase and other penetrations including this unsealed hole for wiring, found beneath the insulation.
The unfortunate result of excess moisture reaching this heavily insulated attic via these air leaks (also known as attic bypasses) was that the moisture condensed on the plywood roof sheathing and began to grown mold.
These photos help show how adverse conditions in one rarely viewed area of the house can lead to additional adverse conditions in another rarely viewed area. The moisture from the crawl space moved up through the wall chases as vapor and entered the cold attic where it condensed back into water on the plywood in winter. These images show that it is essential that a home inspection include examining these areas as much as possible without risking injury to the inspector or damage to the property. Our inspection report included various recommendations on the correcting these and other conditions, including the fact that the furnace was producing excessive levels of carbon monoxide. Click here to learn more about our services. Click here to return to Moisture Damage topic list.
Stucco home with Chronic Water intrusion
This house was built in 1988. We inspected the house in September 2010. Our first clue of possible trouble came within seconds of arriving. There was a wet spot on the driveway in front of our car (at "D"). There had not been any rain for at least 48 hours prior to starting the inspection. Looking up while standing at the wet spot, the corner of the box bay (with the stacked windows) had water dripping out at "C".
Entering the home, we conducted a test with a moisture meter on the wall near the floor in the room over the garage at "B". The red light on the moisture meter indicated that the wall cavity was damp.
Proceeding upstairs we looked at the small balcony over this area and found that water collecting beneath the balcony decking had a potential entry point at the top edge of the stucco wall surface.
Another area of moisture intrustion was found in the left corner of the left garage which is beneath the entry porch. The block wall at the corner of the garage had signs of chronic dampness including severely corroded electrical conduit at "E".
The history of this house included a stucco repair done in 2002 by a firm no longer in business. These areas of potential dampness had been identified for the sellers in March 2008 by IR thermography done by others, with a recommendation for invasive testing, which was not done. High repair cost estimates led our customer to cancel their purchase agreement. Click here to return to Moisture Damage topic list.
Complex Roof & Missing Flashing
This Minnetonka house was inspected in 2002. The first indication of a problem came was a significant stain on the window jamb in the first floor small bathroom.
The stain was not consistent with condensation since it was much more prominent on one side than the other and not severe near the glass. A moisture meter test of the window top casing found the moisture content 70%. This directed the inspector to the exterior.
The complex roof design included a valley which placed water at the corner between the house and garage and directed water to an eave which ended above the bath window.
Notice the stains where the soffit meets the siding. There also is no "kickout" flashing where the garage roof eave meets the house siding. The sellers disclosure stated that they had experienced an ice dam in the garage valley with leaks into the bathroom window twice in the 12 year history of the house.
The location of the bathroom air supply register below the window helped identify the water flow path down the wall and into the basement.
We removed some of the rim joist insulation to confirm the leak drained out of at least the wall cavity containing the supply air register. The inspection report indicated a high potential for water damage above and below the window and recommended corrections by a roofer and carpenter. We do not know the outcome as our customer declined to purchase the house. Click here to return to Moisture Damage topic list.
The Power of Splashing Water - Linking the clues
The 1993 built house was inspected in 2002. The front view shows a well maintained exterior including a gutter and downspout serving the area over the front door which is protected with a storm/screen door. The one story portion of the house has a valley which drains toward the entry.
This detail of the entry shows the storm/screen door and gutter. They are essential in controlling roof runoff which would otherwise splash onto the entry stoop.
Opening the storm/screen door reveals extensive decay and water damage at the door jamb. This is not consistent with a 9 year old door if it had been protected with by the storm/screen door and rain gutters for its entire 9 year history. The entry floor covering was not uniform and the entry door did not close properly. The basement below the entry was unfinished and removal of the rim insulation revealed extensive water damage to the rim and subfloor.
It was reasonable to conclude that the storm/screen door and front entry gutter were not original to the house and were installed after splashing water had already been recognized as a water intrusion problem. The home seller was not aware of the extent of the damage hidden behind the fiberglass insulation which covered the area shown above. The inspection report recommended correction by a qualified carpenter. The key inspection points in this case, as in many similar cases, are understanding that splashing water has the power to penetrate into any joint or seam in the exterior and will often lead to damage in components that can not readily dry. Also see a similar case at our Inspection Quiz.
Clothes Dryer Vents in attic have the potential for long term damage.
Modern clothes dryers are a great convenience and operate with few problems when properly installed and maintained. Unfortunately many townhouse and condo buildings have upper level dryers which vent up through the attic and out the roof. This puts the vent in an area that is rarely examined and creates the potential for moisture damage in the attic if the vent becomes loose. The photo below shows the lint buildup and moisture staining on portions of the roof sheathing upslope from the vent.
The challenge on this inspection was to determine whether or not the dryer vent was still loose or if it had been corrected. The inspection was conducted on a very hot afternoon and the temperatures in the attic were well over 100 degrees. Fortunately the house was air conditioned. We set the dryer control to "air fluff" (no heat) and turned on the dryer so that it would blow room temperature air into the vent. The infrared thermal image shown below reveals that the vent was leaking - cool air - into the attic.
The air leak is the cool blue spot where the vent penetrates the roof. Our recommendation was to have this vent securely fastened by a qualified insulation firm. An insulation firm is suggested since they are most familiar with working in attics and can correct any insulation that is compressed or displaced during the work.
A home inspection involves noticing a variety of adverse conditions and pursuing the relationships of those conditions to determine the root causes of these conditions. The following photos from one 1990 built suburban Twin Cities home show several adverse conditions which are consistent with long term water intrusion.
The damage at the bottom of the siding panels was the first condition observed and led to a closer examination of the siding and trim on this north facing wall.
The corner at the north and front wall of this house had decayed trim and siding. A knife penetrated 3 inches through the trim and wall sheathing.
The brick veneer in the lower portion of this corner was found to be damp.
Inside the home, the floor frame at the corner behind this damp brick was also found to be damp.
The hardwood floor immediately above this damp frame was checked with a moisture meter and found to have elevated moisture content.
One of the root causes of this dampness was determined to be the lack of rain gutters on the roof above this front corner of the house.
The inspection report recommended corrections of the wall siding, sheathing, framing and any hidden damage by a qualified building restoration firm, including installation of rain gutters on the eaves to reduce splash on the foundation in this area and reduce the potential for roof runoff striking the wall.
One Clogged gutter, one window, rain, & gravity, lead to extensive water damage
Home inspections often present a trail of clues that if followed can find and remove the cause of serious damage to homes. The inspection illustrated here started with obvious water seepage in the basement as shown in this photo of the floor near the south wall a few feet from the electric service panel.
Not only was the floor damp, but the foundation wall was water damaged. The most severe damage and greatest seepage was at the inside corner of the foundation wall. Several areas of the wood floor joists in closed basement rooms had signs of chronic dampness including fungal growth consistent with mold.
The inspection continued on the main floor, where severely damaged window was found over the dampest area of the basement. Damaged plaster, peeling paint, out of level floor, and loose baseboard wall trim, were further signs of water damage in this corner. A look through the top of the window showed a roof eave, gutter, and downspout directly above the window.
A view from the south yard showed that the second story gable created a roof design with valleys that drained to the south roof slopes and that the south east gutter ended directly above the water damaged window.
Climbing a little over one story to view this gutter revealed that the spout was clogged and the gutter was full of water and had been spilling directly onto the poorly patched joint between the stucco wall and the top of the window. The inspector cleared some debris from the spout and a torrent of water flowed from the gutter, through the spout and out onto the south lawn.
Returning to the basement to further examine the water damaged area, insulation was removed from the rim joist area to reveal water soaked subfloor, rim board, and joist ends.
The recommendation was for proper gutter and spout maintenance, and correction of all the water damage by qualified carpenters, including floors, walls, windows, and window flashings.
Obviously the water damage was caused by more than a single failure to clean a clogged gutter, but gutter cleaning both in the short term and over the years, would have greatly reduced the extent and severity of the damage.