Shingle Re-Covers and Deck Checks for San Jose's Post-War and Late-Century Houses

When is a recover the right choice?

A recover is the right choice when there is one sound layer of shingle, the deck is firm, the flashing can be re-made and the attic shows no sign of long-term wetting. Each condition is checked before the decision is made.

A single sound layer gives the new covering a firm base, and the nails of the new layer bite into the deck beneath the old one. The technician checks each condition, and any failure of one of them moves the decision toward a strip.

The owner is told why the recover is chosen, and the reasons are written on the scope. The record makes the decision visible to the next technician, who may need to know whether the old layer was left in place.

Why does a second layer change the decision?

A second layer adds weight to the rafters, hides the condition of the deck and makes the nailing harder to judge. Once there are two layers, the strip to the deck is usually the sounder choice.

Each layer of shingle adds weight, and the rafters of a house built in the post-war decades were not always sized for many layers. A deck that has carried two layers may hide rot that a single layer would have shown, and the strip is the only way to see it.

The count is written into the scope, and the reason for the strip is recorded with it. The owner can then see that the decision was made on the deck, not on the look of the roof.

The owner is also told how the recover affects the roof's height at the eave and at the ridge. A second layer raises the covering by its thickness, and that can change how the gutter and the fascia line up. The technician checks the height at each edge and notes any change, so the gutter can be re-hung if it sits too low afterward.

How is the nailing checked on an existing deck?

The nailing is checked by the pattern and by the hold. A nail that has backed out or been driven into a gap holds poorly, and the new covering is then fixed into the wrong material.

The technician looks at the nails from the attic side, where the points show through the deck. A nail that is pushed up or that has rusted through is replaced, and a new nail is set at the spacing the covering needs.

Plywood decks of the period may have delaminated at an edge. Where a sheet is soft at its edge, the edge is cut back and a new piece is fixed across the joint to the spacing the manufacturer requires.

What about the attic and the vents?

The attic is read for ventilation and for signs of moisture. A vent that was covered by an earlier re-roof is reopened, and the intake is cleared so the new covering is not heated from below.

A covered vent traps heat and moisture and shortens the life of the new covering. The technician reopens the vent, pairs the exhaust with the soffit intake and fits baffles where insulation blocks the eave.

The attic is recorded with photographs before and after the work. The record shows the vents that were added or reopened, so the next check knows the ventilation design.

What should the owner keep after a recover?

The owner keeps the scope, which names the layer count, the deck repairs and the covering. The photographs of the deck and the attic are kept beside it.

The layer count in the scope is the most important line for a later repair. A future technician who knows there are now two layers will plan the next job differently from one who finds only the top layer.

No warranty is stated on this page. The manufacturer's terms and any workmanship promise are read and kept with the scope.

How is the wind lift of a new shingle controlled on an older roof?

The new shingle is fixed to the manufacturer's nail pattern and at the rake and eave where the wind lifts most. The starter course and the drip edge are set so the first row seals at the edge.

Wind lift starts at the edges, where the covering is least held down. The technician checks the starter course, the drip edge and the rake nailing, and each of those is set to the pattern the covering requires. A shingle fixed high in its slot or with too few nails will lift in the first strong gust.

The nailing is checked on a sample of the course after the crew has finished each slope. A nail that has been driven too hard tears the mat, and one that has been left proud lets the next course lift, so the crew adjusts the depth as it goes.