COMMENTARY AND COMPARISONS OF ROOF SYSTEM MATERIALS, CONSTRUCTION AND LONGEVITY – RUBBERIZED ASPHALT VERSUS NON-RUBBERIZED ASPHALT

BEC Roof System – 3 Ply Hybrid Roof System With Type II or Kettle Grade  Rubberized Asphalt

  • I ply of 3.0 mm rubberized, 180 gram polyester reinforcement base sheet in solid moppings of type II asphalt or rubberized asphalt
  • I ply of 3.0 mm rubberized, 180 gram polyester reinforcement base sheet in solid moppings of type II asphalt or rubberized asphalt
  • I ply of a 3.0 mm, 180 gram polyester reinforced, rubberized base sheet
  • Base flashings – 2 plies of 3.0 mm rubberized, 180 gram polyester reinforcement base sheet in solid mopping s of type II or rubberized asphalt
  • All layers adhered withType II asphalt or kettle grade rubberized asphalt
  • Floodcoat of Type II or kettle grade rubberized asphalt applied at the rate of 70 lbs. per square and gravel surfacing applied at a rate of 650 lbs per square 
  • 24 gauge, pre-painted sheet metal details
  • Vapour Barrier – self adhesive, rubberized polyolefin faced vapour barrier fully adhered on a primed metal deck
  • Base course of insulation – 2.5” polyisocyanurate insulation adhered in approved quantities of foam urethane adhesive
  • Intermediate course of insulation – 2.5” polyisocyanurate insulation adhered in approved quantities of foam urethane adhesive
  • Top course of insulation – 1/2 inch, asphalt saturated fibreboard adhered in a solid mopping of type II or rubberized asphalt

BEC – 3 PLY RUBBERIZED BASE SHEET ROOF SYSTEM – RUBBERIZED ASPHALT – ROOF SYSTEM SCHEMATIC – SYSTEM 1

3/8” good quality, roofing gravel OOOOOOOOOOOOOOOOOOOO

embedded in a floodcoat of 

hot rubberized asphalt

1 ply of 3.0 mm, rubberized, 180 gram 

polyester reinforced base sheet fully _____________________________

embedded in a solid mopping 

of hot rubberized asphalt

1 ply of 3.0 mm, rubberized, 180 gram 

polyester reinforced base sheet fully ______________________________

embedded in a solid mopping 

of hot rubberized asphalt

1 ply of 3.0 mm, 180 gram polyester 

reinforced, rubberized base sheet fully _____________________________

embedded in a solid mopping of 

hot rubberized asphalt

Top course of insulation – 1/2” asphalt ______________________________ 

saturated fibreboard adhered in a solid ______________________________

mopping of hot rubberized II asphalt

Base course of insulation –2.5” ______________________________

polyisocyanurate insulation – _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

adhered in an approved volume of ______________________________

urethane foam adhesive – R value 15

Base course of insulation –2.5” ______________________________

polyisocyanurate insulation – _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

adhered in an approved volume of ______________________________

urethane foam adhesive – R value 15

Vapour Barrier 1 ply rubberized, self-adhesive  

polyolefin faced vapour barrier adhered in ______________________________

 full surface primed metal deck

BEC – 3 PLY RUBBERIZED BASE SHEET ROOF SYSTEM – 

NON-RUBBERIZED ASPHALT – ROOF SYSTEM SCHEMATIC – SYSTEM 2

3/8” good quality, roofing gravel OOOOOOOOOOOOOOOOOOOO

embedded in a floodcoat of 

hot type II asphalt

1 ply of 3.0 mm, rubberized,180 gram 

polyester, reinforced base sheet fully _____________________________

embedded in a solid mopping 

of hot Type II asphalt

1 ply of 3.0 mm, rubberized, 180 gram 

Polyester reinforced base sheet fully _____________________________

embedded in a solid mopping 

of hot Type II asphalt

1 ply of 3.0 mm, 180 gram polyester 

reinforced, rubberized base sheet fully _____________________________

embedded in a solid mopping of 

hot Type II asphalt

Top course of insulation – 1/2” asphalt ______________________________ 

saturated fibreboard adhered in a solid ______________________________

mopping of hot type II asphalt

Base course of insulation –2.5” ______________________________

polyisocyanurate insulation – _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

adhered in an approved volume of ______________________________

urethane foam adhesive – R value 15

Base course of insulation –2.5” ______________________________

polyisocyanurate insulation – _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

adhered in an approved volume of ______________________________

urethane foam adhesive – R value 15

Vapour Barrier 1 ply rubberized, self-adhesive  

polyolefin faced vapour barrier adhered in ______________________________

a full surface primed metal deck

Comparison Chart For Two Roof Systems – BEC

ComparatorBEC System #1 – 3 Ply Rubberized, Composite Ply Sheet Roof System – Kettle Modified
BEC System #2 – 3 Ply Rubberized, Composite Ply Sheet Roof System – Type II
SubstrateMetal Deck 
Metal Deck 
Vapour Retarder1 ply, rubberized, self-adhesive, polyolefin faced adhered on fully primed metal deck
1 ply, rubberized, self-adhesive, polyolefin faced adhered on fully primed metal deck
Base Insulation2.5 inch polyiso adhered in an approved volume of urethane foam adhesive on a fully adhered vapour barrier
2.5 inch polyiso adhered in an approved volume of urethane foam adhesive on a fully adhered vapour barrier
Base Course of Insulation½” asphalt saturated  fibreboard adhered in a solid mopping of hot rubberized asphalt
½” asphalt saturated  fibreboard adhered in a solid mopping of hot Type II asphalt
Top Course of Insulation½” asphalt saturated  fibreboard adhered in a solid mopping of hot rubberized asphalt
½” asphalt saturated  fibreboard adhered in a solid mopping of hot Type II asphalt
Base Ply Of Membrane1 ply of 3.0 mm, 180 gram polyester reinforced, rubberized base ply in a solid mopping of hot rubberized asphalt
1 ply of 3.0 mm, 180 gram polyester reinforced, rubberized base ply in a solid mopping of hot Type II asphalt
2nd Ply of  Roof Membrane1 ply of 2.5 mm, composite, polyester/fibreglass, reinforced, rubberized base ply in a solid mopping of hot rubberized asphalt
1 ply of 2.5 mm, composite, polyester/fibreglass, reinforced, rubberized base ply in a solid mopping of hot Type II asphalt
3rd ply of Membrane1 ply of 2.5 mm, composite, polyester/fibreglass, reinforced, rubberized base ply in a solid mopping of hot Type II asphalt
1 ply of 2.5 mm, composite, polyester/fibreglass, reinforced, rubberized base ply in a solid mopping of hot Type II asphalt
Surface FinishGravel surfacing embedded into a heavy floodcoat of hot rubberized asphalt
Gravel surfacing embedded into a heavy floodcoat of Type II asphalt
Membrane AdhesiveRubberized, virgin asphalt, kettle grade – applied hot
Type II roof asphalt applied hot
Renewal of Surface Required During Service Life of System?No, gravel and floodcoat are essentially permanent
No, gravel and floodcoat are essentially permanent
Top Floodcoat MaterialHot applied, rubberized, virgin asphalt with exceptional weathering resistance applied at a rate of 70 lbs. per 100 sq. ft.
Hot applied, Type II applied at a rate of 70 lbs. per 100 sq. ft.

Warranty
Standard – typically 10 years – more can be purchased – see Notes
Standard – typically 10 years – more can be purchased – see Notes






Estimated Service Life of System45 years plus, plus – essentially a permanent roof
25-30 years plus 
Resistance To LeakageExcellent – the multi-layer membrane features redundant waterproofing, exceptional toughness and resistance to puncture – essentially seamless
Excellent – the multi-layer membrane features redundant waterproofing, exceptional toughness and resistance to puncture – three very robust plies
Resistance to Traffic Excellent – the polyester membrane is extremely tough and robust and the adhered gravel surfacing provides protection from traffic and damage
Excellent – the membrane is extremely tough and robust with three plies of polyester reinforcement and the adhered gravel surfacing provides protection from traffic and damage
Ease of Leak Source IdentificationExcellent – the multi-layer membrane is extremely  tough, all layers are completely adhered together – holes in the membrane are extremely unlikely. If a hole is made by great force – water will not be able to migrate and the hole will be obvious
Excellent – the multi-layer membrane is extremely  tough, all layers are completely adhered together – holes in the membrane are extremely unlikely. If a hole is made by great force – water will not be able to migrate and the hole will be obvious
Low Temperature Flexibility
Excellent – entire system flexible to – minus 20oC minimum- rubberized polyester reinforcement is flexible to coordinate with the flexibility of the rubberized asphalt
Good – all plies are rubberized and reinforcement contains much flexible polyester – Type II asphalt is rigid
Resistance to Thermal ShockExcellent – entire system is elastic and movement tolerant over full range of ambient conditions
Good – robust polyester reinforcement is elastic and all plies are rubberized – Type II asphalt is rigid
Elongation and RecoveryExcellent – 700% plus elongation with over 95% recovery – rubberized asphalt and polyester reinforcement  is extremely flexible
Good – Polyester reinforcement is very flexible but is restrained by the rigid Type II asphalt
Puncture resistanceExcellent – the roof membrane is composed of a polyester, flexible base sheet and three extremely durable, polyester ply sheets that are virtually impervious to puncture – in addition the rubberized asphalt provides “squirm” puncture resistance
Excellent – the roof membrane is composed of a polyester, flexible base sheet and two composite plies with more polyester extremely durable, ply sheets that are virtually impervious to puncture – the floodcoat of asphalt and gravel surfacing increases toughness
Perimeter Base Flashing SystemExcellent – base ply of high strength solid, rubberized flexible, polyester reinforced flashing sheet is covered with a solid cap ply of flexible, rugged polyester cap sheet – both layers adhered  with rubberized asphalt which provides exceptional movement tolerance
Excellent – base ply of high strength , solid, rubberized flexible, polyester reinforced flashing sheet is covered with a solid cap ply of flexible, rugged polyester cap sheet  – both layers adhered in and with Type II asphalt 
Resistance To Ponding WaterExcellent – the top floodcoat of rubberized asphalt and gravel surfacing are resistant to the effects of ponding – entire system is non-rotting – full rubberized system is resistant to ponding conditions – polyester is superior
Good – the top floodcoat of Type II asphalt and gravel surfacing are resistant to the effects of ponding – the entire polyester/fibreglass system is non-rotting  
Resistance to Ultraviolet and Heat agingExcellent – the rubberized asphalt is resistant to heat aging and the SEBS rubber compound highly resistant to ultraviolet attack is highly resistant to ultraviolet attack that is integral is highly resistant to ultraviolet attack
Good –the coated rubberized ply sheetsare  resistant to ultraviolet attack  and the top floodcoat of Type II asphalt  enhances the resistance of the ply sheets