Installation of new shingles over existing wood shakes or worn asphalt shingles can create a warped, waving appearance. Johnson Roofing & Construction does not install shingles over existing material. We always tear off existing shingle layers down to the roof deck, ensuring a clean, properly prepared surface. Not only does this create a nice, clean, and uniform appearance, but it also helps protect your home from water infiltration, algae build up, and other issues that may develop under the new shingle layer. Moreover, by removing all existing shingle layers we are able to assess the condition of existing decking. Any soft or rotten decking is replaced before installing underlayments, flashings, and shingles, ensuring that your roof will protect your home for decades.
Current building code requires a layer of underlayment to be installed between the roof deck and shingle layers. Traditional construction methods typically used roofing felt – a mat of fibers pressed together to form a sheet and impregnated with asphalt. Another form of underlayment is produced synthetically using a type of nylon mesh. Synthetic underlayment provides better protection against water infiltration and creates a smoother surface to enhance the appearance of the shingle layer after installation. We currently use traditional roofing felt when the roof pitch is below 7/12 and we use synthetic roofing felt on steeper roofs.
Current building code requires flashing to be installed at wall and roof intersections, at gutters, wherever there is a change in roof slope or direction, and at all roof openings. Johnson Roofing & Construction installs corrosion-resistant flashing metals in compliance with all building codes and we always replace valley metal, drip edge, gutter apron, and other flashings with new material. Variables can affect the size requirements and placement of flashing material. When you choose Johnson Roofing & Construction to install your next roof you can rest easy knowing that we are aware of and comply with all current building codes – ensuring that your home will be protected for decades.
Hot air can accumulate and get trapped in attic spaces, which can cause moisture problems. Proper roof ventilation helps remove hot air from your attic. Johnson Roofing & Construction always replaces standard roofing vents and caps with new material. We will also advise placement of new vents if needed, and we replace all roof penetration boot flashings. We typically install adjustable neoprene boot flashings against PVC piping. However, lead boot flashing is always used against metal piping – the kind that are common among older plumbing exhaust pipes – because neoprene will deteriorate over time if installed against metal pipes.