Box gutters & slate
Box gutter repair in Pittsburgh: built-in and slate-roof gutters
If your house was built between about 1900 and 1930 in Squirrel Hill, Shadyside, Highland Park, Mt. Lebanon or Dormont, there's a good chance the gutter is built into the roof edge behind the cornice. When it fails, the water goes into the wall. This guide to box gutter repair in Pittsburgh, PA explains the options; it's work many gutter crews don't do.
What a box gutter is
A box gutter, sometimes called a built-in or Yankee gutter, is a wooden trough at the roof edge, framed as part of the cornice and lined with metal — originally tin or galvanized steel, sometimes copper. From the street you don't see a gutter at all, just a deep cornice. The roof, usually slate, runs into it, and it drains through an outlet to a downspout on the wall. Thousands of Pittsburgh brick homes and rowhouses from the 1900s through the 1920s have them, and they were built well enough that a lot of the original linings lasted seventy years.
They don't last forever. The lining develops pinholes, the soldered seams crack under freeze-thaw, and water gets into the wooden trough and the cornice behind it. The first sign is usually paint peeling on the cornice, a damp stain on the plaster at the top of a second-floor wall, or a stretch of brick that stays dark for days after rain.
What proper box gutter repair involves
Relining. If the wooden trough is sound, the old lining is cleaned and the gutter is relined. On most homes that means EPDM rubber membrane, fully adhered to a new plywood or board base, lapped up under the slate and over the front edge. It's seamless, flexible in cold, and good for 25–30 years. Copper relining costs more, lasts longer, and is the right choice on a house where the cornice and downspouts are already copper. Either way, the outlet and the first section of downspout should be replaced at the same time, because that's where box gutters fail first.
Rebuilding the trough. When water has been in the wood for years, the gutter boards and sometimes the ends of the rafters are rotted. The gutter is opened, the bad wood cut out, the framing sistered or replaced, the trough rebuilt to its original profile, and then lined. This is carpentry as much as gutter work, and it's why the price is per foot with a range.
Slate roof gutter work. Many of the same houses have hung gutters on a slate roof, or a mix — box gutter on the front, hung half-round on a rear addition. Slate cracks if you walk on it wrong or drive a fastener through it. Expect roof hooks and staging, hangers that fasten to the fascia or through the slate with proper flashing, and broken slate replaced to match, which is the standard any slate roofer will tell you to expect. Get that last point in writing.
Box gutter replacement with aluminum: when not to
A common mistake is a K-style aluminum gutter nailed to the face of the cornice with the failed box gutter left behind it. The water still goes into the wall — it just does it out of sight, and the cornice rots from inside. On some homes the box gutter can be properly decommissioned: the trough is filled, sloped and roofed over, the slate is extended, and a hung gutter takes over. That's a legitimate option worth asking about. Covering the problem isn't.
What it costs
| Work | Typical Pittsburgh range |
|---|---|
| EPDM relining, sound trough | $35 – $60 per foot |
| Copper relining, sound trough | $90 – $160 per foot |
| Gutter board and framing rebuild | $40 – $120 per foot, added to lining |
| New outlet and downspout connection | $250 – $600 each |
| Decommission and convert to hung gutter | $50 – $90 per foot |
| Hung gutter on slate, half-round aluminum | $14 – $22 per foot |
One side of a typical 30-foot rowhouse front relined in EPDM with a new outlet is usually $1,300–$2,400. A full wraparound on a Squirrel Hill four-square with rot at two corners runs $6,000–$12,000. Those are ranges, not a quote; the wood decides most of it, and nobody can see the wood until the gutter is open. Ask whether the inspection includes opening a small section so you can see it too.
Yankee gutter repair
Pittsburgh's older suburbs also have Yankee gutters on shingle roofs rather than slate — a trough built up on the roof surface itself, near the edge, lined with metal. It's the same relining job, and the same rule applies: fix the lining, don't cover it. If the roof is due for replacement, that's the time to decide whether the Yankee gutter stays or goes.
Signs a built-in gutter is failing
- Paint peeling on the cornice or the soffit below it, often in one spot that keeps coming back
- A water stain on a second- or third-floor ceiling near an outside wall
- Brick that stays dark for days after rain under one stretch of roof edge
- Icicles hanging from the face of the cornice rather than from the gutter edge
- Rust stains or drips where the downspout leaves the cornice
- Moss or plants growing along the roof edge
Questions to ask about the job
- Will you open a section so I can see the wood before the price is final?
- Do you reline in EPDM, copper or both, and which suits this house?
- How is hidden rot priced once the trough is open, and will you ask before going ahead?
- How will you work on the slate, and how are cracked slates handled?
- Will the outlet and the first section of downspout be replaced?
- What written warranty applies to the lining and to the workmanship?
Looking after a relined gutter
Clean it twice a year like any other gutter, and keep the outlet clear above all; a built-in trough that backs up holds a lot of water against the cornice. Check the cornice paint each spring. A small blister caught early is a patch. A season of ignored peeling can mean wood repair all over again.
Getting an estimate
Box gutters are worth a specialist. Requests from this site go to an independent local contractor partner; ask whether they reline in EPDM, copper or both, how they work on slate, and how hidden rot is priced once the gutter is open.
Related
Ice makes all of this worse, because a box gutter holds a lot more ice than a hung one; ice, snow and gutters in Pittsburgh explains why the north side of a Highland Park house is where the cornice fails first. For the hung-gutter side of the same house, see gutter repair, and for what a plain replacement costs, the pricing page.
Other gutter services
Gutter Repair
Leaking corners, sagging runs, ice-dam damage, separated downspouts and soft fascia — what each repair involves and what it typically costs.
Gutter Repair →Seamless Gutter Installation
Seamless aluminum formed on site to fit every wall, sized for western Pennsylvania rain and snow load, with 3x4 downspouts where the roof needs them.
Seamless Gutter Installation →Gutter Guards
Micro-mesh, screen and reverse-curve guards compared, with a straight answer on which ones survive maple seeds, oak leaves and a hard February freeze.
Gutter Guards →Gutter Cleaning
What a proper cleaning includes: every run cleared by hand, downspouts flushed, debris bagged, and a ladder look at hangers and fascia.
Gutter Cleaning →Questions gutter contractors get asked
How do I know if my house has box gutters?
Stand across the street. If the roof edge is a deep, flat-faced cornice with no visible gutter hanging from it, and the downspout comes out of the cornice rather than a gutter, it's a box gutter. Most brick homes from 1900–1930 in Squirrel Hill, Shadyside, Highland Park and Mt. Lebanon have them; 1950s and later homes almost never do.
Is it cheaper to replace a box gutter with aluminum?
Sometimes, if it's done properly — the trough filled and roofed over and a hung gutter installed. It's rarely cheaper than relining a sound trough, and it changes the look of the house. What is never worth doing is nailing an aluminum gutter over a failed box gutter, which hides the leak and lets the cornice rot.
How long does an EPDM box gutter lining last?
Twenty-five to thirty years when it's fully adhered on a sound base and lapped properly under the slate. The rubber stays flexible below freezing, which is the main advantage over the tin and galvanized linings it replaces. Copper lasts longer — fifty years and up — and costs two to three times as much.
Should a gutter contractor walk on a slate roof?
As little as possible, and never without roof hooks or staging that spread the load. Slate breaks when a boot lands on it at the wrong angle. Ask how the contractor works on slate and whether replacing any cracked slate with a matching piece is written into the estimate.
Need gutter work in Pittsburgh?
Call for a free estimate. Mon–Sat 7am–7pm.