Data · comparisons
Which Roof Options Fit an Older House Best?
Three choices every prewar roof job runs into, compared on the points that matter. For slate options see the synthetic vs. natural slate page.
- Shingle types
- Tear-off vs. layover
- Flashing metals
Are architectural shingles better than 3-tab shingles on an older house?
Usually yes. Architectural shingles are thicker and layered, so they read closer to slate or wood from the street, which matters on prewar houses and in historic districts. They cost more: RoofVista's Pennsylvania guide gives $5.30 to $7.42 a square foot against $3.18 to $5.30 for 3-tab.
Architectural vs. 3-tab asphalt shingles
| Architectural | 3-tab | |
|---|---|---|
| Look | Layered, shadowed; closer to slate | Flat, uniform |
| Published cost (RoofVista, PA, Mar 2026) | $5.30–$7.42 per sq ft | $3.18–$5.30 per sq ft |
| Fit for historic review | Easier to match color and shape | Harder to argue as a slate substitute |
These are published third-party estimates and public fee schedules, dated where the publisher dates them. Not a quote; your price comes after a free inspection. Source: RoofVista, accessed Oct 29, 2026.
Should an old roof be torn off or covered over?
Torn off, in almost every prewar case. A tear-off exposes the board deck so rot and gaps can be fixed, and Philadelphia's EZ Re-Roofing standard requires a full tear-off when the existing roof is slate, is damaged, or already has two or more coverings. Slate can't be covered over at all.
A layover can be cheaper on a newer house with one sound layer, but it hides the deck and adds weight. See the glossary for the terms.
Tear-off vs. layover
| Tear-off | Layover | |
|---|---|---|
| Deck inspected and fixed | Yes | No |
| Over slate | Required | Not possible |
| Philadelphia EZ standard | Required for slate, damaged roofs, or 2+ coverings | Only where none of those apply |
| Weight on the framing | One layer | Adds a layer |
Is copper flashing worth it on an older house?
Copper is worth it where the flashing has to outlast long-lived roofing such as slate, which is why the National Park Service recommends 16-ounce copper on slate roofs. Under an asphalt roof, aluminum or galvanized steel flashing sized to the shingles' life is the common, lower-cost choice, and copper is optional.
On a slate-to-asphalt job, chimney counterflashing is often redone at the same time because the old flashing was set for the slate.
Sources and checked date
- RoofVista, Historic slate roofing in Pennsylvania (Mar 26, 2026) accessed Oct 29, 2026
- Philadelphia L&I, EZ Re-Roofing Permit Standard PB_012_F tear-off rule
- National Park Service, Preservation Brief 29 16-ounce copper
Last checked 2026-10-29.
Rules change. Confirm with the city, township or borough permit office before you rely on any permit or historic-district detail here.
Weighing options for your roof?
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