Reroofing a house means replacing its roof covering, and a full tear-off is the way to see every layer before the new roof goes on. The deck, the underlayment and the old flashing are all visible once the covering is gone, and nothing is left to guess.
Why the tear-off tells you more than a visit does
From above, an assessment sees the covering and the flashing. It cannot see the underlayment, and it sees the deck only at the edges and vents. Once the covering is off, every board and every seam is open to inspection.
That is why a tear-off scope allows for deck work. It says what happens if sheathing turns out to be soft, and who decides.
When a second covering is allowed over the first
Under County rules, laying a new covering over an old one takes three conditions together: just one layer already on the roof, a deck in good, dry condition, and framing strong enough to carry the load (LA County Public Works, BCM 1512, 1 Apr 2025). A roof that misses any one of them has to come off.
This is County jurisdiction. Cities with their own building departments follow their own adopted codes, so the address decides.
What a tear-off scope should say
- How many layers are coming off and where the debris goes
- How the yard, plants and openings are protected
- What happens if the deck is found soft, and who decides
- Which flashing is replaced and which is cleaned and reused
- How each section is dried in before work stops for the day
- Who signs the Re-roofing Certificate of Compliance
Signs a tear-off is the right call
- A covering that has already been laid over an earlier one
- A deck that flexes or feels soft when walked
- Daylight visible through the boards in the attic
- Tile that has to come off before any other material can go on
Tile comes off entirely
Wherever County rules govern, concrete and clay tile has to be taken off completely before any other material is laid, and existing wood shakes have to go too. Tile is heavy, so the removal is planned: where it is staged, how it is lowered, and how the deck is protected between stages.
The City of Los Angeles has its own path for tile that is lifted and relaid, covered on the tile roof page.
What is on the deck when the old roof is gone
Once the covering is off we look at the sheathing, the earlier underlayment, the old flashing and the nail pattern. Where boards are soft or cracked they are replaced. Where earlier work has left gaps or stray fasteners, they are cleared before the new underlayment goes down.
The new roof is then built up in order: underlayment, flashing, covering. The permit office inspects, and the inspection closes the job.
Questions about tear-off
Why must tile come off completely before a reroof?
County rules require concrete and clay tile to be fully removed before any new material goes on (LA County Public Works, BCM 1512, 1 Apr 2025). Tile is heavy and hides the underlayment, so taking it off also lets the deck be inspected properly.
What does a tear-off turn up under older roofing?
It shows the true state of the deck and underlayment, which no visit can. Soft sheathing, earlier layers, stray fasteners and failed flashing all come into view. The scope should say in advance how each finding is handled.
Who protects the house and yard while the old roof comes off?
The scope should list covers over plants and walkways, protection at the gutters and openings, and a plan for debris. Ask for that list in writing before the work is scheduled.
What is a re-roofing certificate?
It is the City of Los Angeles Re-roofing Certificate of Compliance. An owner-builder or the contractor puts a signature on it, and LADBS takes it by mail, or the inspector collects it at the site (form IN.Form.12). The form records that the new roof meets the rules that applied.
Can rain interrupt a tear-off?
Yes, and then the work stops and open sections are covered. A sound scope dries in each section before the day ends. Rain in Downtown Los Angeles falls mainly from November through March (National Weather Service, 1991-2020 normals), so the calendar counts.