![a builder using a gas blowtorch to heat and melt bituminous felt sheet to bond to a flat roof making it waterproof Stock Photo - Alamy a builder using a gas blowtorch to heat and melt bituminous felt sheet to bond to a flat roof making it waterproof Stock Photo - Alamy](https://c8.alamy.com/comp/A97TPA/a-builder-using-a-gas-blowtorch-to-heat-and-melt-bituminous-felt-sheet-A97TPA.jpg)
a builder using a gas blowtorch to heat and melt bituminous felt sheet to bond to a flat roof making it waterproof Stock Photo - Alamy
![a builder using a gas blowtorch to heat and melt bituminous felt sheet to bond to a flat roof making it waterproof Stock Photo - Alamy a builder using a gas blowtorch to heat and melt bituminous felt sheet to bond to a flat roof making it waterproof Stock Photo - Alamy](https://c8.alamy.com/comp/A97TT3/a-builder-using-a-gas-blowtorch-to-heat-and-melt-bituminous-felt-sheet-A97TT3.jpg)
a builder using a gas blowtorch to heat and melt bituminous felt sheet to bond to a flat roof making it waterproof Stock Photo - Alamy
![a builder using a gas blowtorch to heat and melt bituminous felt sheet to bond to a flat roof making it waterproof Stock Photo - Alamy a builder using a gas blowtorch to heat and melt bituminous felt sheet to bond to a flat roof making it waterproof Stock Photo - Alamy](https://c8.alamy.com/comp/A97TR1/a-builder-using-a-gas-blowtorch-to-heat-and-melt-bituminous-felt-sheet-A97TR1.jpg)
a builder using a gas blowtorch to heat and melt bituminous felt sheet to bond to a flat roof making it waterproof Stock Photo - Alamy
![a builder using a gas blowtorch to heat and melt bituminous felt sheet to bond to a flat roof making it waterproof Stock Photo - Alamy a builder using a gas blowtorch to heat and melt bituminous felt sheet to bond to a flat roof making it waterproof Stock Photo - Alamy](https://c8.alamy.com/comp/A97TRD/a-builder-using-a-gas-blowtorch-to-heat-and-melt-bituminous-felt-sheet-A97TRD.jpg)