How do you roof a house with shingles?
Short answer. Roofing a house with shingles follows a fixed sequence: get the permit, tear off to the decking, repair bad sheathing, install drip edge and underlayment with ice and water barrier at valleys and penetrations, flash walls, chimneys and pipes, then lay starter strips, shingles and ridge caps with balanced ventilation. Each step depends on the one before it, and the shingle manufacturer's instructions set the details.
The sequence
- Permit: most Georgia cities and counties require one for a reroof, and rules vary by jurisdiction.
- Tear-off: remove old shingles, underlayment and nails down to the deck. The residential code allows one roof-over in some cases, but not over two existing layers or over wet or damaged roofing, and a tear-off is the better practice.
- Deck repair: replace soft, rotten or delaminated sheets and renail loose decking.
- Drip edge at eaves: required on shingle roofs by the residential code.
- Ice and water barrier: in valleys and around chimneys and penetrations.
- Underlayment: lapped shingle fashion from the eave up, doubled on slopes from 2 in 12 to under 4 in 12.
- Drip edge at rakes, over the underlayment.
- Flashing: step flashing at sidewalls, counterflashing at chimneys, pipe boots and valley treatment.
- Starter strip at eaves and rakes, so the first course has sealant and coverage beneath it.
- Shingles: courses laid at the correct exposure and offset, with at least four nails each in the nailing area.
- Ventilation: intake at the soffits and exhaust at or near the ridge, in balance.
- Hip and ridge caps, then cleanup with a magnetic sweep for nails.
Why it is a pro job
Most leaks on new roofs come from flashing and nailing errors, not the shingles. A full crew also moves fast enough to keep the house dry, and falls are a serious risk for anyone without proper equipment.
See what to expect on roof replacement day, roofing permits in Georgia and roofing over existing shingles.