Conventional Reroof Practices
|A typical low slope roof consists of a roof covering, insulation layer, and structural deck leading to trapped moisture within the roof assembly.
|Conventional roofing practices call for the removal of the entire roof assembly which leads to disruptions for occupants and increased overall cost.
Reduce, Reuse, Renew
Reduce Capital Investment, Reuse Materials, Renew, and be Code Compliant
|Tear off aged roof covering.
|Install SlopeShield Plus SA allowing damp substrates to dry.
|Work continues on reroofing with robust weather protection installed. Building remains occupied.
|Install new insulation layer and roof covering.
How SlopeShield Plus SA Dries Damp Substrates
Proving Substrate Drying: Case Study
SlopeShield Plus SA allowed the double plywood roof deck to dry out over a period of approx. 45 days. The closed cell foam acted as a vapor barrier, negating any downward drying. Only upward moisture movement through SlopeShield Plus SA could take place.
Reducing Captial Investment
Minimizing Occupant Disruption
Challenge: Reroof, reduce labor and capital investment, keep the terminal functional.
Solution: SlopeShield Plus SA allowed:
These benefits reduced overall project costs for owners and contractors.
Challenge: Reroof overburdened vegetative green roof without displacing condo residents on two stories.
Solution: SlopeShield Plus SA allowed:
Owners saved valuable HOA monies for additional improvement projects.
Code Compliance and Energy Efficiency
|Meeting/Exceeding Standards: VaproShield products are meticulously engineered to meet and exceed the standards set forth in IECC and IBC. Our high-quality air and vapor retarder membranes safeguard compliance with these codes, guaranteeing the highest quality and adherence to the regulations.
|Energy Efficiency: As a code compliant air barrier, SlopeShield Plus SA enhances energy efficiency in the roofing system by minimizing heat transfer and reducing reliance on the HVAC system, significantly contributing to energy savings for the life of the building.
Three Story Condo | Portland, OR
In Portland, Oregon, this concept was proven, using SlopeShield Plus SA air and vapor retarder with Self-Drying Technology, in an attempt to dry a wetted plywood substrate. Thereby salvaging the existing substrate materials, including the spray polyurethane foam, interior gypsum ceiling.
Existing Roofing Assembly
|Residents experienced interior water intrusion as a result of leakage through membrane laps and punctures, plus improperly sealed penetration flashings.
|Membrane removal exposed wet coverboard, insulation, and plywood substrate materials.
|The initial moisture meter readings, in the top plywood layer, indicated a moisture content exceeding 40%.
The Solution: SlopeShield Plus SA
SlopeShield Plus SA allowed the double plywood roof deck to dry out over a period of approx. 45 days. Using a Delmhorst BD-2100 moisture meter, measurements taken at regular intervals, documented downward moisture levels in the decking material. The closed cell foam acted as a vapor barrier, negating any downward drying. Only upward moisture movement through SlopeShield SA Plus could take place.
Remediating leaks through rooftop amenity spaces is an expensive process that requires total removal of the overburdened roofing, membrane, and saturated materials, including coverboard, insulation, roof deck, cavity insulation, and interior ceiling. This work is costly (high disposal fees, complete material replacement) and results in temporary resident displacement and revenue loss for the property owner.
Remedy and Findings
The existing materials were removed down to the plywood. The entire deck was covered in SlopeShield Plus SA, allowing the damp substrates to dry through upward moisture vapor diffusion.
The Results: Minimal Impact to Occupants and a New Roof
With a target moisture content at or below 15% it was determined the materials could be reused and the subsequent new roofing components (see above) could be installed.
VaproMat is designed to be installed over VaproShield membranes as a system to provide a positive drainage cavity behind claddings.
AIR BARRIER INSTALLATION
Air barrier installation requires all seams, joints, overlaps and penetrations WRB/AB membrane to be sealed for complete air barrier continuity.
BEST PRACTICES OVERVIEW
- Always install VaproMat, filter fabric side out, vertically with seams butted together, overlapping the 2” filter fabric selvage edge. Do not overlap the drainage matrix.
- Refer to membrane specific installation instructions for proper membrane installation.
- Building layout should be planned prior to installation to minimize waste and ensure all interfaces and penetrations are identified and correctly detailed to protect against water and air infiltration.
- Proper sequencing is critical. Protect rough openings and large penetrations with specified rough opening material.
- Maximum exposure prior to cladding installation is 6 months (180 days).
- Install lath and weep screeds “proud” or over the VaproMat material.
SlopeShield Plus Self-Adhered roofing underlayment offers permanent mass timber roof deck/floor deck protection by allowing vapor to pass through (breathable) but not air or liquid water.
WallShield IT Integrated Tape water resistive barrier (WRB) membrane offers mass timber post, column, and beam protection by allowing vapor and air to pass through but not liquid water.
PanelShield SA is a permeable polyester air barrier (AB) and water resistive barrier (WRB) sheet membrane offers permanent protection for exterior walls by allowing vapor to escape through but not air or liquid water.
SlopeShield Plus SA is installed on the roof deck/floor deck as the structure is erected and taped using VaproTape on the seams. The underlayment can be installed on a low slope (1/4":12 to 2:12) assembly or a steep slope (2:12 or greater) assembly.
WallShield IT is wrapped around post/columns and beams, and uses VaproTape at the seams.
PanelShield SA is designed for exterior walls with rainscreen cladding materials. VaproShield offers additional WRB air barrier membranes for walls including open joint cladding, see individual product data sheets.
SlopeShield Plus SA: spun-bond polyester
WallShield IT: multiple layers of spun-bonded polypropylene
PanelShield SA: spun-bond polyester
All mass timber types:
- Cross-laminated timber (CLT)
- Nail-laminated timber (NLT)
- Dowel-laminated timber (DLT)
- Vertically laminated veneer lumber (LVL)
- Glue-laminated timber (GLT)
- Laminated strand lumber (LSL)
- Timber-concrete composites (TCC)
- Parallel strand lumber (PSL)
- Mass plywood panel (MPP)
For additional substrates view individual product data sheets or contact VaproShield Technical.
Storage and Handling
Store materials on end in original packaging at temperatures between 40°F and 120°F (4.4°C and 48.9°C). Protect materials from direct sunlight and inclement weather until ready for use.
CAUTION: Release liners are slippery. To prevent injury, liner should be removed from under foot as soon as membrane is installed and disposed of properly.
Work crews are safe around VaproShield membranes they contain zero VOCs or toxins.
Persons who access any roofs, involved with roof construction, repair or maintenance shall use appropriate personal protective equipment including, but not limited to, hard hats, eye protection, and leather gloves and must be trained on safe practices relevant to their work.
Where the use of ladders, scaffolds, platforms, or temporary floors are utilized, safety lines and safety harnesses shall be used. Please access the OSHA Web site at www.osha.gov, contact your local OSHA office, or visit the local federal bookstore to obtain the most current information on OSHA 29 CFR 1926.
For self-adhered membranes all surfaces must be dry, sound, clean, “as new” condition, and free of oil, grease, dirt, excess mortar or other contaminants detrimental to the adhesion of the roofing underlayment or WRB air barrier. Fill voids and gaps in substrate greater than ½” (12.7 mm) in width to provide an even surface.
SlopeShield Plus Self-Adhered should be covered within 180 (6 months) of installation with permanent roofing/flooring material. Minimum recommended application temperature of 20˚F (- 6.0˚C) and rising.
PanelShield SA should be covered with cladding within 12 months of field assembly. Minimum field assembly recommended installation temperature of 20˚ F (- 6.0˚ C) and rising.