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WATER ENTRY IN BUILDINGS
AGE of MOLD, HOW OLD
BASEMENT CEILING VAPOR BARRIER
BASEMENT MOLD WATER IMPACT
BRICK WALL DRAINAGE WEEP HOLES
BUCKLED FOUNDATIONS due to INSULATION?
BUILDING DAMAGE ASSESSMENT & REPAIR
CONDENSATION on WINDOWS & SKYLIGHTS
DEW POINT TABLE - CONDENSATION POINT GUIDE
EFFLORESCENCE SALTS & WHITE DEPOSITS
FLOOD DAMAGE ASSESSMENT, SAFETY & CLEANUP
FLOOD DAMAGED FOUNDATIONS
FLOOD VENTS & FLOOD PORTS
FLOODS IN BUILDINGS-mold
FLOOR DAMAGE DIAGNOSIS
FOOTING & FOUNDATION DRAINS
FOUNDATION BULGE or LEAN MEASUREMENTS
FOUNDATION CRACKS & DAMAGE GUIDE
FREEZE-PROOF A BUILDING
FROST HEAVES, FOUNDATION, SLAB
GOPHER HOLE DAMAGE
HUMIDITY LEVEL TARGET
ROOF ICE DAM LEAKS
MOISTURE CONTROL in BUILDINGS
MOLD INFORMATION CENTER
NOISE / SOUND DIAGNOSIS & CURE
ODORS GASES SMELLS, DIAGNOSIS & CURE
SEWAGE BACKUP, WHAT TO DO
SEWAGE BACKUP TEST & CLEANUP
SEWAGE BACKUP PREVENTION
SEWAGE PUMP CLOG DAMAGE
STAIN DIAGNOSIS on BUILDING EXTERIORS
STAIN DIAGNOSIS on BUILDING INTERIORS
SWEATING (CONDENSATION) on PIPES, TANKS
TOILETS, INSPECT, INSTALL, REPAIR
TRAPS on PLUMBING FIXTURES
VAPOR BARRIERS & CONDENSATION in BUILDINGS
VENTILATION in BUILDINGS
WATER ENTRY in BUILDINGS
WINTERIZE A BUILDING
Building siding, window or wall leak detection, diagnosis & repair procedures: this article describes the discovery of both active and prior leaks through a building's walls or windows and the steps that were taken to evaluate the impact of the leaks on the structure, to track down the leak sources, and to fix the problem both in stop-gap mode (due to weather and time constraints) and as final repairs were made to stop future leaks.
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Moisture & Leak Mystery: procedures for tracking down uncertain sources of leaks through a building's exterior siding, trim, walls or windows
Steven Bliss & Daniel Friedman
Just above our photographs illustrate the discovery of leak stains on the carpeting, tack strips, and subflooring that were discovered when first floor wall-to-wall carpeting was removed during building renovations. Rather than pretend to be smarter than we are, we report here the actual site observations and our discussion about them, more or less in the order that they occurred among "new owner" and the authors. The result is a look into the thinking process of a couple of experienced building investigators and builders during the track-down of wall leaks.
Remarks from New Owner are in italics.
Initial Comments on floor leak stain report
When investigating building window or wall leaks or leak stains on building floors along the exterior wall/floor juncture, before tearing the building apart we inspect the building exterior for likely water entry point candidates, and we inspect the interior for evidence of the extent and history of water leaks as well as to assess the risk of water-related rot or insect damage that might require further repairs.
Inside there was not evidence of significant damage to the carpet nor to the subfloor, but we suspected there had been more than one leak event. A report of a prior owner leaving windows open was considered but comparing the location and extent of leak stains on the floor with that story, we doubted that all of the home's windows had been left open repeatedly. Here was our initial reply to New Owner:
While it was natural to suspect that water leakage had passed through the building walls or perhaps around windows, we wanted to rule in or out probable causes of those indoor leak stains on the floor that might be tracked to ice dam leaks that can send water into building walls, and we also wanted to rule in or out leaks at the sidewall flashing of lower roof to building upper walls alongside the dormer.
We even considered that leaks around skylights could have sent water down the roof cavity and into the building walls where it emerged to make those floor and carpet stains shown above.
Follow-up remarks from New
Here is a closeup of the window top or head flashing.
Next Reply to New:
But on this home, an expanded Cape Cod design, there is almost no roof overhang at all.
While we now had some good candidates for possible explanation of the leak stains found inside, it was time for some more invasive inspecting both to assess the extent of leaks and to be sure we understood the leak source(s).
With winter already present and owners needing to make the home dry and habitable as soon as possible, we needed to decide just how much exterior demolition was really necessary to diagnose and cure the leak problem.
On the one hand we didn't want to renovate the home interior without being sure that the building shell was adequately weatherproof, lest we risk new water damage to the planned renovations (a hardwood floor, other indoor improvements).
On the other hand, we didn't want to tear apart the building exterior in cold, probably wet weather, expanding and extending outdoor work and delaying the date at which the home could be occupied.
An advantage of starting invasive inspecting on the building interior is that while removal of an occasional wood clapboard (or exterior siding) and poking into building sheathing might be possible, in general it's easier to fix a hole cut into building interior drywall, exploring the same leaky wall cavity from that side.
In the first pass at invasive interior inspection steps (photo at above left) drywall was removed along the floor in the areas of staining. At below left you can see that water was certainly entering the floor from the bottom of the wall sill plate; you will also notice that a plastic vapor barrier had been installed behind the drywall - a step that permits water to run inside the wall cavity all the way to the floor without making an earlier appearance through the wall surface or in wallpaper stains.
At left you can see the discovery of wet sawdust in the wall - the hope that the leaks were old, and had somehow all been corrected became a fantasy.
There was at least some ongoing or active water leakage.
We noticed some small shiny black fragments mixed in with the sawdust - a carpenter ant alert sign. But the rough texture of the sawdust doesn't look like carpenter ant frass (it was explained as debris from nearby drilling through wood sheathing or studs).
The pair of photos above begin to point to a leak at a window side or sill. At left just above that protruding nail you can see a wet sill plate immediately below an insulated gap between a set of wall stud and jack studs found along side and below typical window framing. At above right is that same location with the insulation and debris removed.
Looking along the other sides of wall studs we see from the stains that water was clearly passing under the stud bottom and out onto the top of the sill plate - arguing for water passing down the wall cavity, not entering from some snafu at the very bottom of the building exterior siding or wall.
The presence of disconnected water stains at the stud bottoms argues for more than one water entry point. As the left side of the photo shows an abutting wall (see that baseboard trim) we wondered if there was additional leakage at the building corner trim outside.
Incidentally, when we see leak stains on subflooring, it's appropriate to remove all of the nearby baseboard trim to check for hidden rot, mold, or other leak stains.
This photo shows the arrangement of wall corner stud (photo left), and the jack studs along the left side of the window being investigated.
While further investigation is needed to be sure of the water entry point (along the window top, side, or sill), the images seen to this point form a strong argument for leaks at the windows.
Further inspection outside confirmed that the brick-mold trim around these windows was quite rotted.
We discussed a stop-gap measure of injecting cold-weather caulk into the most-suspect areas and perhaps some live tests with a garden hose to see if we could make the wall weather tight for the winter, deferring more extensive window repairs or replacements.
We also discussed a strategy of window repairs versus window replacement, but agreed that until we know the exact leak points and extent of window damage, that decision would wait.
Next Reply from New:
Probing & inspection of the building exterior window trim & wall siding to diagnose window or wall leaks
These photographs illustrate probing for leak and rot damage at the suspect windows.
We observed soft rotted vertical brick-mold window trim (photos above).
We also noted that some window sills had been wrapped in brown aluminum coil stock (photo at left).
While the aluminum trip wrap had been pushed up under the (probably already soft, rotted) vertical window trim, this covering of the previously leaky, rot-damaged window sills had not been sealed against further water entry beneath the aluminum.
When covering damaged window sills using aluminum coil stock and where storm windows are installed, for a successful seal against further leaks at the window, the aluminum needs to extend all the way up inside the window sill to abut the interior window sill or stool edge, and all sides of the aluminum must be sealed against further leaks. Otherwise water may simply pass beneath the aluminum where it can continue to leak into the building wall.
At below left you can see that the aluminum window sill wrap was not sealed to the building and that someone has already probed in this location; further probing confirmed that the sill and siding were soft and rotted here, and we pose that perhaps the window king stud will also be found to be leak stained and perhaps even rotted as well.
Back inside the building and examining the sides of the king stud at the window opening we can see what appear to be several water tracking or leak stains down the side of the stud (red arrows).
Comment from New:
[Pending weather changes]
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