COVID-19 lockdowns resulted in a huge spike in roofing repairs and replacements. Many offices used the closures as an opportunity to do much-needed repairs on their existing membranes. This roofing replacement was done in the fall and winter months of 2020/2021, during which time this building was partially open, requiring some creative thinking on our part to get the job done.  

The Specs: 

Type of Project: Full Replacement
 
Roof area: 34,200 square feet
 
Deck Type: Steel 
 
Vapour retardant: reinforced kraft paper with adhesive at side/end laps
 
Insulation: 3″ ISO plus 0.5″ thick perlite

Roof Membrane (field area):
 3 plies type 4 glass, 1 ply #15 perforated felt paper, asphalt and gravel
 
Flashing Membrane (perimeter and roof upturns): 2 ply SBS modified bitumen
 

The Ask: 
Our client had a positive experience with their 30-year-old roof assembly and wanted to use a similar membrane selection.  They reviewed alternatives and ultimately decided to use a hot asphalt applied built-up roof because of the multi-ply redundancy and their long-term experience which provided them with the most comfort relative to other available options.  

The client also evaluated the pricing options for various thicknesses of thermal insulation.  There was a request to increase the R-Value on the roof to improve energy efficiency as our client bears sole responsibility for all of the utility costs. 

Our Approach: 
We used an asphalt and gravel built-up membrane because of its weather resistance and durability, keeping in mind our client’s top priorities.  The odour of hot asphalt was always a concern at the premises during roof repairs we completed over many years.  The COVID lockdown was used as an advantageous time to schedule the roof replacement as the building occupancy level was much lower than usual.  We also used a menthol additive in our asphalt kettle to alleviate the smell of bitumen.  

Work in progress around an abandoned skylight prior to infill of deck substrate.

We removed 7 –  8 feet x 8 feet abandoned skylights and the related curbs.  There were some drywall and metal stud partitions to demolish below the roofline in these areas to allow for the deck infill to be done.

Our team had to work closely with the HVAC sub-trade due to the over 20 HVAC units on the roof.  We arranged to have all of the threaded gas pipe connections removed and welded sections of piping remained in place. We were responsible for lifting the HVAC equipment using our own gantry crane and the HVAC sub-trade took care of gas, electrical and ducting connections and modifications. Our team had to ensure that the roofing work that needed to be done with the heating disconnected was executed on a rotating basis based on the needs of the two larger tenants and the partial closure of the building.

There was an area of ponding water that required the addition of (1) new roof drain.  Our service plumber completed the connection from the new drain to the rain water leader.  We also discovered several additional plumbing issues that were reported to the building owners and remedied while we were on-site.  The plumber extended plumbing vent terminals and insulated the underside of roof drains to prevent condensation issues.

Even with these challenges, the project was extremely successful. The previous roof for this building lasted over 30 years, and we are confident that this replacement will hold up exceptionally well during extreme weather. If you are looking for information on replacing or repairing your roof, contact us here