HomeMy WebLinkAboutB18-0152_approved plans_1529097016.pdf
The existing shingles are CertainTeed Weathered Wood
The new shingles are to be CertainTeed Weathered Wood
06/15/18
CyberCon Consulting, Inc.
Quality Service Performance
July 5, 2017
Paul Huntoon
Vail Management Company
100 West Beaver Creek Blvd., Suite 230
Avon, Colorado 81620
Attn: Mr. Paul Huntoon
Ref: Roof Evaluation
Columbine West Condominiums ' 2833 Kinnickinnick Road, Vail, Colorado 81657
Dear Mr. Huntoon:
At your request, the undersigned performed an assessment of the asphalt/fiberglass shingles on the southwest building at the
Columbine West Condominiums in Vail, Colorado on March 30th, 2017 to determine if the reported leaks and water stains on the
ceiling are related to roof defects and/or condensation. This assessment is based on a visual inspection of the roof, interior space
and crawl space below the structure and interviews with property management and one of the occupants. The interior walls were
also scanned with a Flir infrared camera to inspect the ceiling and walls for signs of water intrusion or condensation.
The information available in this report should assist the asset manager with expense and capital spending objectives. Opinions of
probable costs for roof repairs, preventative maintenance and roof replacement are summarized in the Budget Summary table
provided within this report. The cost estimate for roof replacement is based on installing a “cold roof” system. Following, please find
this writer’s findings, conclusions, recommendations and budget estimates for a new cold roof system:
I. ROOF DESCRIPTION:
A. The steep gable-style roof has heavy duty fiberglass/asphalt three-dimensional shingles over underlayment and
an ice and water dam protection membrane over the plywood deck with a 4:12 pitch that slopes to the sides of the
building, similar to a Swiss chalet. Three major wood beams (perpendicular to the slope) at the ridge, midpoint of
each roof facet and at each eave, extend out from the fascia board. The roof structure was constructed as a
cathedral ceiling with a painted gypsum sheathing installed directly to the bottom of the roof joists with fiberglass
insulation batts installed between the joists. This type of roof/deck/ceiling assembly is known as a “self-drying” roof
system and has no means for cross-ventilation. Three chimneys penetrate the roof, one at the ridge and two on
each facet, close to the eave. The chimneys are clad with plaster stucco with sheet metal caps. Flue pipes
penetrate the metal caps and dryer vents penetrate the sides of the chimney cladding. Grill style vents were also
installed on the side walls of the chimneys to vent the chase. The roofs have overhanging eaves and rakes that
form soffits on all four sides of the structure. There is no ingress ventilation on the underside of the soffit and no
gutters along the eaves. A low profile Velux skylight was installed on the roof and various soil vent pipes
penetrate the roof.
II. OBSERVATIONS/FINDINGS:
A. The three-dimensional shingles are showing normal signs of age and wear except along the eaves where ice
dams tend to occur and the seasonal ice removal process has caused some damage to the shingles. A few
shingle tabs were also noted to be missing, probably due to exposure to strong winds. The flashings at the roof
penetrations, chimneys and skylight appeared to be performed in accordance with industry standards. One
deficient soil vent pipe flashing was noted that could be causing a leak.
6482 South Quebec, Bldg. 3, Centennial, CO 80111-4628 ® P.O. Box 621832, Littleton, CO 80162-1832
Business Phone: (303) 741-6020 ® FAX: (303) 741-5776 ® E-Mail: cyberconengineer@qwestoffice.net
06/15/18
Roof Evaluation Report Columbine West Condominiums ' Vail, Colorado
B. The counterflashing around the chimney was surface-mounted and relies on silicone sealant for its watertight
integrity. These joints could become a source of water intrusion and need to be periodically maintained. The
chimney caps appear to have been a source of water intrusion in the past. One of the chimneys has been
overlaid with an aluminum-skinned peel-and-stick membrane. Nail holes were also noted in the other chimney
caps, leaving a path for water to infiltrate the chase. The chimney caps were inadequately fastened and are prone
to wind damage.
C. One of the pipe flashings was noted to have a collapsed and torn rubber collar that was improperly repaired with
roofer’s mastic and is prone to water intrusion. The flat tops of the cantilevered roof beams have been retrofitted
with metal caps and sealant. In the past, water has migrated through the building envelope through cracks in the
wood member and joints between the beams and the siding. The metal caps and sealant repairs appear to have
remedied the leak issues.
D. The low profile Velux skylight has been sealed around the frame with generous amounts of silicone sealant,
suggesting past leaks. No signs of leaks were noted inside the space below.
E. The interior inspection revealed dark stains along the exposed beams and water damage to the paint and dry wall
sheathing board in localized areas, which suggests condensation issues with the roof/deck/ceiling assembly. As
expected, the infrared scan of the ceiling indicated a thermal short at the roof beams, making them prone to
condensation. The cavity between the cathedral ceiling and roof deck has a tendency to accumulate moisture
during the colder months of the year which turns to frost on the underside of the deck. The frost eventually melts
during warm winter or early spring days, causing water to drip down into the living space below. Occupancies that
progressively generate moisture from various sources, including but not limited to, cooking, showering, unvented
clothes dryers, aquariums, humidifiers, etc. tend to be more prone to condensation issues. Ground water or damp
soil in the crawl spaces can also be a source of water vapor migration into the building envelope.
III. DISCUSSION:
A. The subject building is located in alpine conditions, described as a high elevation with a cold and snowy climate
for at least 6 months out of the year. These climatic conditions have a propensity to create ice dams along the
eaves, valleys and dormers due to melting snow caused by heat loss from the building and daytime solar
radiation. The dramatic temperature fluctuations from day to night cause the melting snow to freeze along the
eaves, valleys, and shaded areas. The accumulation of ice causes freshly melted snow to dam up against the
mass of ice, causing hydrostatic pressure on the roof shingles and underlayment. This condition worsens in the
spring with the first major thaw. The north and east elevations are more prone to ice dam formation due to the
limited direct solar radiation during the day and the abundance of shaded roof areas.
B. Eagle County building codes and practices, require ice dam protection membrane over the substrate along the
eaves and valleys of steep roof systems. Contractors and designers have also used ice and water dam protection
membrane indiscriminately over the entire roof deck to protect the building envelope against leaks, which can
cause moisture issues with roofs that are not adequately vented. Ice dam protection membrane functions as a
water barrier and also acts as a vapor barrier. If it is not placed appropriately in the envelope, it can trap moisture
and promote condensation within the building envelope, resulting in water damage and mold growth. Vapor
retarders should be installed on or near the warm side of the building envelope to prevent moisture laden air from
diffusing up into the colder regions of the roof assembly, which will eventually condense into liquid water when it
contacts a cold surface (where the temperature falls below the dew point).
C. A “cold roof” retrofit is often used to address issues with condensation. Proper and adequate ventilation of the
space below the roof is essential for a “cold roof” to perform. A cold roof is designed to allow cold ambient air to
enter soffit ingress vents which then flows underneath the roof substrate and exits through an egress vent along
the ridges, high eaves or roof-to-wall flashings. The flow of cold air below the roof prevents heat loss from the
interior of the building from warming the deck and maintains the roof near the outside ambient temperature which
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Roof Evaluation Report Columbine West Condominiums ' Vail, Colorado
prevents the snow on the roof from melting and causing ice dams. Cross-ventilation also provides a “drying effect”
and reduces the moisture accumulation in attics and rafter spaces of cathedral type ceilings. A cold roof assembly
above a cathedral ceiling should incorporate a vapor retarder membrane and thermal insulation over the structural
deck. To achieve proper cross-ventilation, the intake and exhaust net free ventable areas should be equal and
separated as much as possible between the eave and ridge. The ingress and egress areas should be protected
from wind-driven snow and rain. Protrusions through the roof and architectural features, such as chimneys and
dormers, interrupt the cross-ventilation and can promote ice dams around these appurtenances due to building
heat loss and shadows where melted snow is prone to refreeze. There are two basic methods utilized to construct
a “cold roof” over a cathedral ceiling:
1. Option #1 is to install a vapor retarder membrane on the deck and then 2X6 wood stringers that run
parallel with the slope and a second plywood deck over the stringers to provide a substrate for the roof
system. Insulation board measuring 3" thick is placed between the stringers over the vapor retarder,
leaving a gap or space between the insulation and the supra deck to provide a chute for ventilation.
2. Option #2 is to install a vapor retarder membrane on the deck and then install a composite ventable
insulation/OSB board product with spacers between the insulation and the OSB supra deck. This option
eliminates thermal shorts.
A continuous ingress vent along the eave and an egress vent at the ridge are incorporated into the design of both
options to allow the cold outside air to flow over the insulated portion of the cold roof assembly.
D. Snow retention devices are used to prevent snow slides which can cause roof damage and/or danger to property
and persons. A properly designed cold roof should prevent the accumulated snow from melting, keeping it on the
roof until it has a chance to drain off of the roof naturally during the spring months. Some melting snow from solar
radiation should be expected, which will cause icicles to form along the eaves. Snow will also curl under the soffits
or overhangs, which may cause damage to windows and other building components. The slope and roughness
affect the ability of a roof to retain snow. Roof pitches greater than 4:12 generally require snow retention devices
to prevent the snow from sliding off of the roof. The proper design and installation of snow retention devices is
critical to the performance of a steep roof and protection of property and persons below the roof eaves. The
forces created by sliding snow and ice are usually greater than imagined. The snow retention system should be
engineered to withstand the anticipated loads. Most manufacturers can provide design assistance and it is highly
recommended that their services be used. Snow fences are much easier to install on standing seam metal roofs,
compared to shingles.
IV. CONCLUSIONS, RECOMMENDATIONS AND BUDGET ESTIMATES:
A. It is this writer’s professional opinion that the water damage to the upper units is the result of occasional
condensation within the cathedral roof/deck/ceiling assembly caused by diffusion of moisture that is generated by
the normal activities and occupancy of the units. To correct this issue, it is recommended that the existing roof
shingles be torn off and a “cold roof” system implemented with new underlayment and shingles or metal roof
panels installed.
B. The chimney caps also need to be replaced. The flue pipes and vents that run through the chimney chase should
be inspected to ensure that there are no breaks or loose joints where moist air or exhaust can escape and infiltrate
the space.
C. It is further recommended that the exposed chimney walls be re-clad with new sheathing, underlayment and siding
with proper flashings, closures and trim. The exposed beams should also be capped and sealed to prevent water
migration back into the building. Due to the marginal slope and orientation of the gable ends on the front and
back of the building, snow retention is considered optional. The pros and cons of snow retention should still be
considered by the ownership.
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Roof Evaluation Report Columbine West Condominiums ' Vail, Colorado
V. BUDGET ESTIMATES:
A. The estimated cost to tear off the existing shingles and furnish and install new underlayment/vapor barrier, thermal
rigid insulation with a vented supra deck, wood nailers, ingress and egress vents, metal flashings, trim and
accessories, chimney caps and new cladding over the chimney walls is approximately $44,000, based on a
estimated roof area of 2,300 sq. ft.
B. The optional cost to furnish and install snow fences is approximately $6,500.
C. The reroof cost does not include the consulting fees for design and project management.
VI. LIMITATIONS:
A. This writer’s findings are based on a visual inspection of the roof, interior spaces and crawl space. Destructive test
cuts were not taken in the roof or walls to determine the components of the roof/deck/ceiling and wall assemblies.
The original plans and specifications were not reviewed.
B. No warranty is hereby being expressed or implied.
C. This roof evaluation report is exclusively for the use and benefit of the Vail Management. This report is not for the
use or benefit of any other entity, nor may any other person or entity rely upon the report without the advance
written consent of CyberCon Consulting, Inc. Extreme weather events, change in building use, improper tenant
improvements, and a lack of maintenance, will have a direct adverse effect on the performance and useful and
serviceable lives of the roofs.
D. The opinions and reasonable order of magnitude costs presented in this report are based on current municipal
codes (unless otherwise stipulated), observations, and information available at the time of the inspection. Actual
costs will vary depending on many unforseen factors and price adjustments. The costs presented herein are
intended for budgeting purposes only. Preparation of a scope of work, plans and specifications are recommended
to determine the actual costs to perform the work outlined. Should additional information or conditions be
discovered, CyberCon Consulting retains the right to supplement and revise this report.
„
Thank you for the opportunity to be of service. Please do not hesitate to call our office if you have any questions or would like to
discuss this report in more detail.
Sincerely,
Nick A. Lovato
President/Sr. Consultant
Enc: Photograph Report
Infrared Scan Photograph Report
Atlas Nailable Cross-Vent Cold Roof Design Details & Information
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North
Roof Slope 5:12
40ft
30ft
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