2018 Repair irs and Repair ir Opti tions movin ing forw rward - - PowerPoint PPT Presentation

Western Fin inancial Pla lace

Cit City of f Cr Cranbrook Co Council il Prese sentatio ion

February 25th, 2019 Presentation by: Building Consulting Services Kevin Wilkins

2018 Repair irs and Repair ir Opti tions movin ing forw rward

• WPF has been experiencing moisture issues for many

years.

• The existing TPO roof membranes have reached the

end of their life cycle and are showing their age.

• Over the past few years RJC and IRC have completed

reports on the roofing issues. Both of those reports provide a very detailed and valuable review of the roof assemblies, cut test, components, budgets and

• ther related issues.
• Our report and opinions are based on our own review

and much of the information provided within those

• reports. BCS did not complete cut tests.
• The IRC report uses a numbering system for the

different roof areas. We have maintained that same numbering system in our report for consistency between report.

The WFP roof areas are as follows;

• 1.1 - Office Patio (Mechanical Fastened - MF)
• 1.2 – Rear Entry Roof (MF)
• 1.3 – Rear Canopy (?)
• 2.1 – Stair Roof (MF)
• 2.2 – Change Rooms (Fully Adhered - FA)

& Concourse Roof (MF)

• 2.3 – Arena Exit (MF)
• 2.4 – Arena Exit (MF)
• 3.1 – Restaurant Roof (New SBS in 2018)
• 3.2 - Pool Roof (FA)
• 3.3 – Racket Ball Roof (MF)
• 4.1 – Arena Roof (MF)
• 5.1 – Elevator Roof (MF)

Mechanical fastened roofs are typically used

• ver normal humidity environments, where

Fully Adhered membranes are recommended

• ver high humidity environments like Pools

and Change Rooms.

• While both the RJC and IRC reports are very detailed,

there is limited information as to exactly when and where within the complex the water issues have

• ccurred, as the City could not provide such records.
• Through discussion, it seems the roofs generally do not

leak throughout the year during normal rain fall, other than at a few select locations, like as seen at the yellow tarp in the Concourse.

• It is BCS’s opinion that the majority of the water issue
• ccur in early spring during warming cycles after long

extreme cold cycles.

• BCS has asked the City to review and document any

water issues within the complex through this 2018- 2019 winter to assist in confirming our opinion. Roof leaks year round.

Current Condit itions of f Roof Systems TPO membrane is aged and deteriorated:

• Cracks and splits
• Reduced flexibility in old

TPO membrane due to age (i.e.brittle)

• Stretched membrane

Pool Roof

• Adhesive failure in the fully adhered roof
• Insulation buckled up
• Repaired in 2018

Insulation de-bonded and lifted off vapour barrier

Stretching and Deterioration of f Roof f Membranes

• Wind uplift forced on Mechanical Fastened TPO creates stretching forces
• Air movement within billowing TPO moves vapour around in the assembly

Conditions that cause moisture issues in roof systems:

• Cold outside temperatures create

thermal variances & vapour drive.

• High humidity interiors combined

with warm temperatures

• Air movement under the membrane
• Wind induced from membrane billowing
• Air leakage from interior through

penetrations and at roof junctions/perimeters

• Insulation installed in one layer.
• Insulation board move around due to

window suction loads.

• Gaps between joints of insulation

boards develop.

• Heat transfer through metal fasteners.

Roofs with a single layer of insulation reduces thermal resistance

Improvements with double layered insulation

• 2 layers of insulation
• Fully adhered, no fasteners
• Insulation gaps lapped.

• In review of the original construction drawings, BCS has

concerns about the location of the vapour barrier within many of the constructed roof edge assemblies.

• Poor vapour barrier construction was confirmed during

dis-assembly of the Restaurant roof.

• The Parapets should have been designed to include a

vapour barrier at the red line, (as seen to the left), at the bottom of the parapet, to close off and prevent vapour from entering the cold parapet.

• Within the constructed parapets, when vapour enters and

contacts cold surfaces it condenses back to moisture, and if cold enough will freeze. More vapour is then drawn in, contacts the cold surfaces, condenses and continues to freeze and begins building up frost within the parapet construction.

Parapet: is the upstand wall located at roof edge.

At WFP… LEFT: Thermal representation of parapet’s internal temperatures. RIGHT: Resulting potential frost zones within the parapet in cold climate. The higher the humidity within the building the greater the amount of frost.

Here are some examples (from other buildings) with roof frost build up within a roof assembly due to interior vapour loss. When all this frost melts it results in many gallons of water running back into the

• building. This is not a roof
• leak. Replacing roof

membranes does not fix this.

• In consideration of these cold parapet

locations and internal frosting, in the image to the right, the thick red line shows the location of the parapets immediately adjacent or above high humidity locations.

• BCS assumes the red line locations are

the areas of the building where the majority of the water issues occur in warming weather cycles.

• The City is in general agreement, and is

monitoring it this winter.

• Conclusion: Parapet vapour barriers

must be repaired as part of any roofing repairs or replacement.

The parapet/wall location along the Restaurant/Arena was repaired during in 2018.

Moisture within Assemblies and RISK The GREEN area is the Restaurant roof and was replaced in 2018. The RED areas have moisture above and below and/or within the insulation, are delaminating and require replacement. The YELLOW areas are recommended for repair and only have moisture within the assembly at the top of the insulation at the dew point. The RISK

• f probably failure is LOW for these
• roofs. So a proper repair could last 20

plus years.

Repair and replacement options

The options reviewed in our report were;

• Repairing with cover strips (An option, but not recommending)
• Repair with a liquid applied coating

(No longer an option, due to manufacturer’s change in warranty as they are no longer providing a Flaking and Peeling warranty.)

• Complete removal and replacement with new TPO roofing.
• Complete removal and replacement with SBS roofing.
• Spray foam application to Arena barrel roof, (an option only for the arena).
• We have just added an option of EPDM membrane replacement, with a manufacturer’s

warranty and possibly an RCABC warranty, which will be discussed later in this

• presentation. We are still working with the manufacturer with respect to details.

Carlisle Fleece EPDM Repair

• Black EPDM rubber roof
• Provides a warmer roof due to

solar heat gain

• Adds additional insulation, R-2.5
• Lowers the dew point down into

the insulation producing better characteristics for drying the roof

• 20 year roof membrane warranty,

and possibly a RCABC Warranty

• Less disruption to building.
• RISK: Frosting may occur in the

unrepaired parapets over low humidity environments, (LOW RISK).

Intent of Repair Option

• Remove existing TPO membrane and

let moisture dry from top of TPO for a few hours.

• Remove insulation at parapet and

install new vapour barrier to seal ends

• f insulation.
• Adhere down new Rapid Lock Cover

board.

• Install new EPDM membrane.
• COST RISK: Must replace any

saturated insulation.

• COST RISK: If insulation is loose and

/or damaged in the fully adhered systems all the insulation & vapour barrier will be required to be replaced for that roof area.

Restaurant Roof Repairs completed in 2018

• The Arena / Restaurant wall was repaired in 2018.
• The old TPO roof was removed.
• New SBS roof was installed with higher R-value to meet code..
• Poor parapet vapour barrier details were repaired around the perimeter of

the Restaurant Roof and Elevator roof.

• A substantial leak was discovered and repaired at the Elevator roof that

was leaking into the Stair below.

• With the Restaurant roof and wall repaired, there have been no further

moisture issues/leaks below these areas.

• We placed RED and GREEN dye within the Arena Roof to

monitor any moisture within the Arena roof. The GREEN dye washing out as seen in the photo indicates a fair amount of moisture flowing on top of the vapour barrier. At this point in time, we are uncertain whether the moisture is from vapour loss and frost, or if the TPO is leaking.

• We are still monitoring and considering

further testing.

• What this means is….

Arena/Restaurant Wall

• Repaired in 2018

Arena Roof Overhang

• Existing condition

Arena/Restaurant Wall

Continuous Membrane.

?

Moisture moving on top

• f vapour

barrier.

Unknown

Water staining Arena Soffit Overhang adjacent Elevator Shaft Leak discovered and repaired in 2018

Roof Repair and Replacement of Assemblies

• Roof assemblies over HIGH HUMIDITY ENVIRONMENT are recommended to be replaced

with fully adhered roofing system. To avoid having screws penetrating the structural decking.

• The Carlisle Fleece backed EPDM is a viable repair over LOW HUMIDITY ENVIRONMENTS

and will provide a 20 year plus solution with little RISK, providing the parapet vapour barrier is repaired over high humidity locations.

• Spray Foam Option is an effective option for the Arena with the following Caveats;
• Requires HIGH quality Spray Foam applicators for install and maintenance.
• Requires ANNUAL review, maintenance and repairs.
• Additional in-house costs for City staff to coordinate, etc.
• If not properly maintained the result could be costly required repairs.
• Annual maintenance is critical to long term performance.

Cost Comparison to Previous Reports

• BCS budget and the previous budget are in line with each other. In

fact, we referred to and re-validated some of the sq.ft. costs in the IRC report and carried similar numbers in our budget. Differences In Budget

• The IRC budget only provides an R-20 roof assembly. Could not

validate R-value in the RJC report. The BCS report provides an R-30 to meet the current Energy Code.

• The IRC budget does not include parapet repairs to correct the

vapour barrier issues. Parapet repairs are included in the BCS budget.

• BCS budget include a 2% rate of inflation per year, that would be up

and above the RJC and IRC reports. Example: 2 years since RJC report.

Completing Repairs and Action Steps moving Forward

• City to determine intent and select final options.
• Select Consultant to complete the work.
• Tender package production, Permitting and Tender will

take approximately a 2 month time period.

• Depending on selected roofs to replace and/or repair,

construction work would be 3-6 months.

• Best to start construction in mid June, past the rainy spring

season.

• BCS can provide all required Consulting Services.

End of Presentation

Thank You Building Consulting Services Kevin Wilkins Open for Q&A…