Some of Newark's best roofs are also its oldest. In Forest Hill and parts of the North, West and South wards, houses built a century or more ago still carry slate roofs, copper valleys and decorative details that later roofs rarely match. Owners of those houses face a choice when leaks start: repair the slate or replace it with something else. This guide explains why repair is usually the better answer, what goes wrong with slate, and how historic district status can affect the work.
Forest Hill, Briefly
Forest Hill sits in Newark's North Ward near Branch Brook Park. It developed in the late 19th and early 20th centuries with large homes, mansions and colonials, and it contains the Forest Hill Historic District, which is listed on the state and national registers. Newark has several other designated historic districts and individual landmarks, listed by the city. Slate shows up across these older areas, not only in Forest Hill.
Why Slate Lasts
Slate is natural stone split into thin pieces. Good roofing slate absorbs very little water and doesn't break down in sun or frost the way asphalt does. That's why a slate roof installed generations ago can still be shedding water today. The stone isn't usually the weak link.
What Actually Wears Out
| Part | What happens over time |
|---|---|
| Nails | Iron nails rust, and slates slip out of their courses |
| Valleys | Metal where two roof planes meet wears through |
| Flashing | Step and counter-flashing at chimneys and walls corrodes or pulls loose |
| Built-in gutters | Gutters hidden in the cornice crack and leak into the wall below |
| Individual slates | Cracked by falling limbs, ice or people walking on them |
| Old repairs | Tar and cement patches trap water and damage slate around them |
When you see a slate on the ground, it's usually a nail that failed, not the stone.
Repairing Slate
A slate repair replaces broken or missing pieces with matching slate, secured with copper nails or slate hooks, and renews the metal at valleys, chimneys and walls. Roofers who work with slate use roof ladders, hooks and planks so their weight never sits on the stone. Matching matters for appearance. Salvaged slate of the same type and size is often used, so the repair blends in. Copper flashing is the usual choice on these roofs and ages to match.
When Replacement Comes Up
Replacement makes sense when the slate itself is failing: soft, flaking or delaminating across large areas. It also comes up on roofs damaged by years of improper patching. Before agreeing to replace a slate roof with asphalt, get an opinion from a roofer who repairs slate regularly. Many slate roofs that look tired from the ground are sound stone with failed nails and flashing.
Historic Districts and What They Can Mean
In a designated historic district, changes to what a building looks like from the street may need approval through the city's historic preservation process before work starts. Repairing slate with slate, or replacing worn copper with copper, usually doesn't change appearance. Swapping slate for asphalt shingles, changing the roof's shape or removing decorative details might. Rules depend on whether the designation is local, state or national, and what the local ordinance covers, so check with the City of Newark before planning a material change. The contractor may know the process from past work.
Living With an Older Roof
- Keep gutters, especially built-in gutters, clear and in good repair
- Keep tree limbs trimmed back from the roof
- Never let anyone walk on the slate, including satellite or cable installers
- Fix slipped slates promptly; an open spot lets water reach the deck
- Ask for copper or compatible metals in repairs, not tar patches
Questions
How long does a slate roof last?
Good slate can last far longer than asphalt shingles, often many decades and sometimes over a century. The nails and flashing usually need attention long before the stone does.
Can slate be repaired in winter?
Small repairs often can, in dry weather. Slate is brittle in the cold and slippery when wet, so roofers pick their days carefully.
Is slate repair expensive?
It's specialized work, and slate and copper cost more than asphalt. Over the life of the roof, keeping sound slate usually costs less than replacing it. The contractor sets the price after looking.
My insurer wants to replace slate with shingles. Is that allowed?
That depends on the policy and on any historic district rules that apply. Ask your insurer and the city before agreeing to a material change.
Older Homes Nearby
Slate and older roofs are common in Forest Hill, Roseville and parts of Orange. The repair side: slate & older roofs.
Repair or Replace? How Roofers Make the Call
The factors that tip a roof one way or the other.
Nor'easters, Ice Dams and Winter Roof Leaks
What winter does to roofs, and why the leak shows up in March.