A construction
defect is generally defined as a defect or deficiency in the design, the
construction, and/or in the materials or systems used on a project that
may not be readily observable and results in a building, structure or
component that is not suitable for the purpose intended. The term
“construction defect” includes both design and construction defects that
result in financial harm (either property damage or personal injury) to
the owner or to a third party.
According to the Insurance
and Risk Management Institute, a construction defect is generally
speaking, a deficiency in the design or construction of a building or
structure resulting from a failure to design or construct in a
reasonably workmanlike manner, and/or in accordance with a buyer's
reasonable expectation. The most dangerous defects have the capacity to
fail, resulting in physical injury or damage to people or property.
However, many defects present no increased risk of injury or damage to
other property but nevertheless cause harm to the property owner in the
form of loss of use, diminution in value, and extra expenses incurred
while defects are corrected. This latter type of defect is often
referred to as a passive defect.
Many states have more
specifically defined the term "construction defect" for purposes of
applying statutes that dictate processes for remedying and litigating
construction defect claims. These statutory definitions vary by state.
Nevada, for example, uses the term constructional defects and defines it
as follows:
“Constructional defect” means a defect in the
design, construction, manufacture, repair or landscaping of a new
residence, of an alteration of or addition to an existing residence, or
of an appurtenance and includes, without limitation, the design,
construction, manufacture, repair or landscaping of a new residence, of
an alteration of or addition to an existing residence, or of an
appurtenance:
1. Which is done in violation of law, including, without limitation, in violation of local codes or ordinances;
2.
Which proximately causes physical damage to the residence, an
appurtenance or the real property to which the residence or appurtenance
is affixed;
3. Which is not completed in a good and workmanlike
manner in accordance with the generally accepted standard of care in
the industry for that type of design, construction, manufacture, repair
or landscaping; or
4. Which presents an unreasonable risk of injury to a person or property.
Whether,
and to what to extent, coverage applies in liability policies for
claims alleging construction defects is a matter of serious debate both
in insurance circles and in the courts. We wrote few weeks ago about
some earthshaking decisions reached by the majority of the jurisdictions
during 2013 and 2014, finding construction defect coverage under a
contractors’ CGL policy. These policies, however, are subject to
numerous exclusions and Anti-Indemnification Statutes, Right to
Repair/Cure and Statutes of Limitations and Repose. In fact, the
defendants in many of these cases have been successful in defeating
claims using the defenses of the statutes of limitations and repose.
Among
the more frequently addressed exclusions are the so-called “business
risk” exclusions, which include the “damage to property”; “damage to
your property”, and “damage to your work” exclusions. Other potentially
applicable exclusions concern prior work; contractual liability; EIFS;
mold; owned property; earth movement, and known or continuing injury or
damage. Claims for damages resulting from defective drywall began to
appear in about 2005, and courts have frequently addressed whether the
standard pollution exclusion, in addition to the above-mentioned
exclusions, bars coverage for such claims.
Basic Categories of Construction Defects
There
are several categories of construction defects depending on the area of
the building or foundation that was affected by defective construction.
· Site Defects
· Building Envelope Defects
· Structural Defects
· Heating, Ventilating, and Air Conditioning Defects
· Electrical and Plumbing Defects
· Fire/Life Safety System Defects
Types of Construction Defects
There
are two types of construction defects, latent and patent defects.
Latent defects are those defects that are concealed and are often not
obvious or readily observable upon reasonable inspection. Even with the
most comprehensive on-site inspections, sometimes defective construction
may go unnoticed. After construction is complete, Latent Defects are
unknown and generally undiscoverable and will only appear after the
passage of time.
Examples of Latent Defects are:
Soils that were not properly compacted.
Improperly installed flashing and/or the total lack of flashing within the building envelope assembly.
Lack of reinforcing in structural concrete footings, walls and/or slabs.
Lack of brick ties and/or masonry reinforcement in a brick/masonry veneer wall.
An improperly installed weatherproofing system.
Improperly installed stucco or EIFS exterior wall system.
Improperly consolidated concrete.
Reinforcement not fully embedded in the concrete structure.
Patent
Defects are those defects that are known or would be readily obvious
upon reasonable inspection. Examples of Patent Defects are:
· Weep holes not installed in brick veneer walls.
· Handrails omitted in stairways.
· Missing control and/or expansion joints.
· Cracking and/or signs of distress in the building envelope.
· Lack of roof drainage and/or roof slope.
· Lack of proper roof/attic ventilation.
An
important distinction to understand in the analysis of construction
defects is the difference between the “defect” itself and the
“manifestation” of the defect, although in general terms, both the
defect and the manifestation of the defect must ultimately be corrected.
At times these concepts are erroneously considered to be the same and
are discussed as if they were synonymous.
In fact, the
manifestation of a particular defect is the apparent visible condition
of the building, structure or component that gives the observer notice
of the possible existence of, and most likely results from, a defect in
construction. For example, a crack in a brick veneer wall may be
considered to be a defect, but, in fact, it is only the manifestation of
a defect. The actual defect may be the result of the failure of one or
more components of the brick veneer wall system such as improperly
installed or missing flashing; improperly installed or missing expansion
joints; improperly installed and/or missing reinforcement; lack of or
improperly installed vapor barrier; and/or the improper installation of
the brick veneer wall itself.
Examples of the manifestation of a defect include:
· A total or partial collapse of the structure.
· The inability of the structure to prevent water intrusion.
· Cracking, selling or subsidence of concrete flat work.
· Cracking, settling or tilting of walls.
· Doors that are out of plumb and do not fit into the frame.
· Windows that do not operate.
· Foundations that settle crack or subside.
The
importance of distinguishing between the manifestation of the defect
and the defect itself is critical as the manifestation may provide
clues that a Latent Defect exists and further investigation is warranted
and necessary. The manifestation of a defect may be the first
indication to the owner of a potential problem. Depending on the length
of a warranty and in light of the time limitations imposed by a State’s
statutes of repose, quick action, notification and possible litigation
may be necessary to protect the owner’s rights.
CAUSES OF FAILURES OF BUILDING ENVELOPES
One can think of a building envelope as being similar to envelopes used
to mail packages through the postal service. A standard package mailing
envelope is used to protect the interior contents from moisture, wind
and damage while in transit. The building’s envelope acts like a mailing
envelope by protecting the structure from rain, sleet or snow.
A
building’s envelope includes the walls, siding, flashing, roof,
foundation and so forth. These systems should work together by providing
a barrier between the interior of the structure and the exterior
environmental elements such as rain and moisture. The installation
materials and methods used in the building’s construction will determine
how heat, air and moisture travel through the structure.
This
year, the construction industry is rapidly approaching the $1 trillion
mark. Based on past damage claims, we would expect that there will be
about $100 to $200 billion worth of construction defect-related claims.
The risks causing these damages include design risks, material risks,
construction risks, maintenance risks, and weather-related risks.
Based
on extensive analysis of the construction defects over the past 100
years, we can safely say that wall design, wall material, construction
and maintenance practices are the most significant factors responsible
for the occurrence of the building envelope defects.
Below, we present a number of construction defect photos, illustrating some of the property damage caused by such defects.
DETAILS OF A TYPICAL, PROPERLY CONSTRUCTED, RESIDENTIAL BRICK WALL DRAINAGE SYSTEM
Flashing at the Bottom of Brick-Veneer Walls
Improper
through-wall detailing and installation. No weep holes, and the
flashing did not extent enough on either direction. Also, the caulking
is deficient. As a result, the steel angle lintel corroded and there was
a collapse as well.
This
is an example of properly shingled through-wall flashing system. As you
can see here, the black flashing is on top of the brick ledge. It goes
up onto the framing, and is behind the weather-resistive barrier(WRB)
(white sheet folded out of the way near top of photo). When the WRB is
folded down, it will protect the sheathing from moisture damage due to
capillary action.
Failed sealant in need of replacement
Improper design and installation
Damage due to improper installation
This
picture clearly displays a problem that we call mortar bridging. This
occurs when sloppy workmanship results in mortar getting behind the
brick. The problem is that this prevents water from freely draining out
of the wall system. In fact, it even bridges the gap between the brick
and the framing, allowing water to wick into wood materials, causing
lots of problems.
Building
codes require that weep holes - holes placed at the base of a masonry
wall - be spaced every 16 to 32 inches on center. Here you can see that
these weep holes (where the holes are at) are placed directly above the
through-wall flashing. If water gets behind this brick, it can freely
drain down and be wicked out through these ropes to daylight.
Failed sealant, allowing water to infiltrate the wall
This
picture shows what happens when the weep holes get plugged. You can see
here that there is water trapped at the base of this brick-veneer wall.
It will eventually leak through the building paper and cause moisture
problems.
An
improper installation of a stainless steel flashing is shown in this
image. The edge is held back from the face of the wall. This will allow
water that collects on the flashings to run around the edge of the
flashings and back into the wall.
An
improper installation of flashings and rope wick weeps in a wall system
is shown above. Note that the flashings do not meet and obviously
cannot be lapped and sealed. The rope wick weep is laid in a mortar
joint approximately 3/8 inch above the flashings, meaning that any water
collecting on the flashings will not be able to be picked up by the
rope wick until it reaches the height of the rope wick on the interior
of the wall.
As
you can see here there is no air space between the brick and the
weather-resistive barrier (WRB), which means there is no pathway for
water to freely drain out. Water can easily get trapped behind here,
leading to moisture damage. There should be at least a 1-inch airspace
between the brick and the WRB.
Failed sealant allowing water to infiltrate
Failed terracotta window surround
EPDM
thru-wall flashing membrane is a flexible EPDM rubber membrane that
forms a moisture retarder in cavity wall construction by redirecting
water to a building exterior
Misaligned rigid board insulation exposes this airspace to water bridging
The mortar bridging and impaction in this two-inch airspace are unacceptable
Flashing for Wood and Fiber-Cement Siding
All
cladding systems leak. It's not a matter of if, it's a matter of when.
It's important to understand that proper moisture management dictates
that when water gets through penetrations, we want this water to drain
down the wall freely, and exit the wall at the base of the siding.
That's why the detailing and integration of flashings are so critical to
building long-lasting, durable buildings.
In
this photograph we can see that this home has cement-board siding over
foam board sheathing. Even though foam board sheathing is not affected
by moisture, codes still require that we have a weather-resistive
barrier (WRB). As you can see here, the butt-joint of this siding lines
up perfectly with the seam in the foam. So in a wind-driven rain, it
would be very easy for water to penetrate this seam, get in between the
foam into the wall cavity where it can cause lots of damage. It's
critical to have a properly shingled WRB that directs the water
downward, where it can exit freely.
This
photograph shows an example of improper drainage at the base of the
wall in conjunction with cement-board siding. The moisture build-up in
the siding shows that the wall is not getting free drainage. One of the
problems here is there is not enough space between at the bottom of the
siding and that through-wall flashing. There should be at least 1/8 inch
gap to prevent capillary action. And it's important that the flashing
be properly integrated behind the weather-resistive barrier for proper
shingling of water away from the house.
In
the photograph on the left, we can see that we have T-111 siding. These
T-111 siding panels may not be long enough to side the entire structure
without a seam. So here for example, we have two pieces of T-111 siding
covered by a trim board. In the photo on the right, we can see there is
a substantial amount of damage due to water leaks at the seam where
these two pieces of T-111 plywood meet. You can also see that there was a
thin piece of metal Z-flashing, but it was not adequately sized, nor
properly integrated with the weather-resistive barrier to provide free
drainage to the base of the wall.
It's
fairly typical for wood or cement-board siding to be installed tightly
up against the building wrap, and this can restrict drainage. So
manufacturers have created rain-screen materials and drainage wraps. The
photo on the left shows a rain-screen product. This is a plastic matrix
that is about 1/4-inch thick that facilitates drainage, and provide an
air space that helps prevent capillary action, so water can drain down
the wall system and exit at the base of the siding. The product on the
right is a drainage wrap material. These are different than an standard
building wrap in that they have a texture, or in this case, plastic
deposited on the surface to create a space for drainage. It doesn't take
much or an air space to create better drainage.
Early Deterioration and warping. Note fungus growing on bottom edge.
Edge
Checking and swelling. Although each manufacturers product varies
slightly the bottom edges should be around 7/16" thick with no swelling
present. This area has swelled to over 9/16".
Flashing at the Bottom of Stucco Walls
Stucco
is a popular cladding material because it can be durable and long
lasting, and it doesn't require a lot of maintenance. However, it is
important to follow a few building science principles relating to water
management to ensure that the stucco does not trap water or let water
into the wall assembly.
A
couple things are wrong in this picture: The stucco runs all the way to
grade, and there is no weep screed. The bottom of the stucco must have a
weep screed to allow water to drain out of the wall system, and this
screed should be at least 8 inches above grade. If the stucco runs all
the way to grade, moisture from capillary action can wick up into the
stucco, and transfer to wood framing.
This
picture illustrates how important it is to have a good water management
system behind stucco. You can see that rain water has been absorbed
into the cracks. Now all stucco cracks; that's fairly common. But that's
why it is so important to have a good water management system. Most
building codes requires two layers of building wrap, or building paper,
and that must be integrated with a weep screed flashing at the base of
the wall.
This
is a picture of properly integrated flashing at the base of the wall.
You can see the stucco screed is perforated - has holes in it - so when
the stucco is troweled over the top, it has the capacity to allow
moisture to drain through it. What's important to note here is that the
back flange on the screed goes up behind the paper, so any water that
does get behind the stucco will hit the paper, run down, hit the stucco
screed and drain down through the perforations.
In
this picture, the stucco screed is reverse shingled at the base of the
wall. You can see that the metal flashing is actually in front of the
black paper. To be properly shingled, the black paper should overlap the
metal stucco screed. That way, when water gets behind the stucco, it
runs down the paper onto the metal flashing and is diverted to the
exterior.
It's
a fairly common building practice to integrate multiple types of
cladding on a single wall. For example, here we have stone at the base,
with a cap, and then we have stucco at the top. The problem in this
photograph is where the stucco interfaces with the capstone: There's no
through-wall flashing. Any water that gets behind the stucco, can run
down the wall and get trapped by the stone. Note there are no weep holes
in the stone, so there's no way for the water to get out. It's always
best practice to put through-wall flashing where you have this
transition between one cladding system and another.
Water-Managed Adhered Concrete Masonry
Adhered
concrete masonry is a term used to describe synthetic stone. Synthetic
stone is different than real stone in that it's lighter weight and
therefore can be supported by the existing wall system. However, to make
it lighter weight, it is much more porous and is considered to be a
"reservoir" cladding system (i.e. it holds water). That's why it's
important to have a good drainage, particularly at the base of the wall.
The
construction sequence is as follows: Typically you have your exterior
sheathing, two layers of weather-resistive barrier and perhaps a
drainage mat. Then you have you mortar base, your wire lath and your
synthetic stone.
These
photographs describe the drainage space, or drainage mat, mentioned
previously. This is installed over the weather-resistive barrier to
create a space that allows any moisture that gets in behind the stone to
drain freely down the wall system and out the flashing at the base of
the wall.
For
adhered concrete masonry veneer to work properly, you have to have
adequate drainage at the base of the wall. This means proper integration
of your stucco screed, your flashing and your weather-resistive barrier
at the base of the wall. You can see that this stucco screed is at the
base of the wall and that the weather-resistive barrier is shingled over
the top of it.
It's
common practice to use other cladding systems with adhered concrete
masonry veneer. Here we have a transition point at the base of the
siding where it meets the base of the capstone. Below that we have our
synthetic stone. It's critical that we have good water management here
to divert water away at these siding-to-stone transitions. We want to
have through-wall flashing here that diverts water away from the siding
to the exterior.
The
moisture damage on this home was a direct consequence of improper
detailing of the synthetic stone. There are a couple problems: If you
look at the photograph on the left, you can see that the synthetic stone
runs all the way to grade (in fact, on this home it ran below grade).
Also note that at the cap stone at the base of the siding, there was no
through-wall flashing to divert water out, before it got into the stone
wall. If you look at the photograph on the right, you can see that water
got in at the top near the cap stone, ran down the wall, was absorbed
by the sheathing and then rotted out the framing and the sheathing at
the base of the wall. This is all the direct result of not having
adequate flashing at the base of the wall.
Improper design and installation
Improper detailing and installation resulting in trapped water
Water-Managed Vinyl Siding
Because
vinyl siding has an air space behind it, it acts like a rain screen. As
you can see from this photograph, the water tracks down the foundation
wall indicates how freely this siding can drain. In fact, you do not
need flashing at the base of the wall with vinyl siding because it has
weep holes at every course, allowing for free drainage. You do need to
use a weather-resistive barrier. Also, you would need to use flashing at
the base of the wall if that siding transitions to a trim board or to
another type of cladding.
At
first glance, vinyl siding may not appear to be a very water-tight
cladding system. But if used with a weather-resistive barrier can be
quite effective. The beauty of vinyl siding is that it hangs loosely on
the wall, and creates a fairly good air space between the vinyl and the
weather-resistive barrier, allowing water to drain freely from the wall
system.
Weep
holes are at every course of siding. As you can see here, water can
freely flow out of the weep holes, rather than being trapped inside the
wall system.
Can
you spot what's wrong with this picture? The workers are installing
vinyl siding but there is no weather-resistive barrier behind it.
Building codes now require that there be a weather-resistive barrier
behind all exterior claddings.
Common callback: This damage was caused by a leak at the base of wall cladding that did not include proper through-wall
flashing. Typically, these wall leaks are caused by missing flashings, or poorly executed flashing details at the following:
roof-to-wall intersections
penetrations
windows and doors
transitions
between different claddings when more than one cladding is used at the
bottoms of exterior walls where cladding systems interface with the
foundation.
The key to eliminating costly leaks
is more than just applying a piece of flashing. You need to create a
functional wall assembly
that:
Deflects water away from sheathing, framing and floor-to-foundation intersections.
Drains water as fast and freely as possible to prevent water from being trapped and absorbed by building components.
Dries.
Select building materials that allow the wall to dry out when it gets
wet, and avoid materials that have the ability to trap moisture.
We
are effective negotiators and work hard to resolve cases in a manner
that avoids the additional time and expense of a trial. We help both
insurers and insureds with water damage claims regarding:
Stucco: When a
builder improperly installs stucco or the building paper behind it,
water can seep in and cause damage to the building's framing and
sheathing.
Siding: When a builder improperly installs vinyl or steel
siding or the housewrap behind it, water can seep in and cause damage to
the building's framing and sheathing. Additionally, poor installation
may cause the vinyl or steel siding to warp or buckle.
Leaky roofs: Roof
leaks are often caused by faulty construction, including poor shingle
installation, failure to install kickout flashing and the use of
defective shingles.
Foggy, leaky, or
improperly installed windows: Improperly installed flashing can allow
water to seep around and through the windows and into a property. This
can damage the windows, causing them to rot. It can also cause damage to
the building's framing and sheathing.
Water leaks can quickly
damage and ruin property. And, left uncorrected, water leaks can lead to
pervasive mold growth. We assist our clients in addressing these
construction defect and property damage claims against their builders to
repair these problems. From our offices in several Northeast and
Midwest states, we assist clients facing construction defect issues
across a ten state coverage area.
Metropolitan
Engineering, Consulting & Forensics (MECF)
Providing Competent,
Expert and Objective Investigative Engineering and Consulting Services
P.O. Box 520
Tenafly, NJ
07670-0520
Tel.: (973) 897-8162
Fax: (973) 810-0440
We are happy
to announce the launch of our twitter account. Please make sure to follow us at
@MetropForensics or @metroforensics
Metropolitan
appreciates your business.
Feel free to
recommend our services to your friends and colleagues.
United States of America 
