Asphalt Fillet Repair

Repairs to 19 year old Mastic Asphalt Roof

This office Building roof was laid in 1988, BSS 6925 Roofing Grade with a partial coverage of BSS 1447 Paving Grade runway for a wheeled window washing gantry.
The gantry has been mothballed since.
Because of the differing stone content between the Roofing and Paving Grades, there has been some thermal movement and the junction is cracking in the Roofing Grade.
If left to deteriorate these cracks would open up right through the 19mm thickness to the concrete substrate and cause the roof to leak.
This project was about digging out the existing cracked fillet and replacing with new Roofing Grade Mastic Asphalt. (approx. 1000 lineal feet of)
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view of the asphalt roof, east side, looking south towards Port Nicholson view of the south side, looking west view of the north side, looking west view of the west side, looking north some surface crazing in the Roofing Grade mastic asphalt, approx 5-10mm deep another example of the cracking of the fillet at the internal intersection of the two grades of mastic asphalt an example of the cracking of the fillet at the intersection of the two grades of mastic asphalt on the outside of the paving grade near the outside perimeter of the roof an example of crazing of the roofing grade and cracking of the fillet at the internal upstand of the Plant Room an example of the cracking of the fillet at the intersection of the two grades of mastic asphalt near the air conditioning water tower fence wall an example of the cracking of the fillet at the intersection of the two grades of mastic asphalt on the inside area of the roof close up view of the fillet cracking - a severe example another example of the cracking of the fillet at the intersection of the two grades of mastic asphalt on the outside perimeter on the east side the blocks of mastic asphalt loaded to the plant room level the repair pot heating the asphalt down to molten form the blocks are broken up smaller and melted down in a small LPG fired bucket repair pot dipping the mastic out of the bucket the first step is to heat up and dig out the old fillet with a hot trowel some repair preperation to surface crazing in the Roofing Grade mastic asphalt on the west side which takes the sun most of the day close view of the dig out the second step is laying the new mastic asphalt and forming to the 45 degree angle laying new fillet on a warm November day close view of the new fillet new fillet to the outside perimeter, west side working in the shade on a hot day working outside the perimeter fence, fully harnessed new fillet to internal section south side the third step is to warm the edges between the new and the old mastic close up of the completed repair completed section east side looking south a completed section of new fillet, west side completed repairs to the Roofing Grade on the west side closer view of the completed repairs to the Roofing Grade, west side the crazing repaired with new mastic asphalt new fillet to the outside perimeter, north side new fillet to the outside perimeter, south side the fourth step is to coat the repair with a bituminous aluminium paint for UV protection using a soft broom to paint the repair is easier on the back same section with the UV coating the outside edge in previous pic completed east side, reverse view of previous pic