We replace acrylic domes, and we also swap them for glass. Both are real jobs and we quote both. If you ask us which one we would put on our own roof, the answer is usually glass, and this page explains exactly why so you can decide for yourself instead of taking our word for it. What we will not do is drop a new dome onto a curb that is already rotten and call it fixed, because that leaks again by the spring.
Nobody in this trade writes this down, because whichever one they stock is the one they recommend. We supply both, so here it is straight.
| Acrylic dome | Glass unit | |
|---|---|---|
| Clarity over time | Yellows and hazes under full sun. On a New York flat roof with no shade you see it inside of ten years. | Stays clear. Glass does not discolour. |
| Rain noise | Loud. A hard rain on a plastic dome is audible in the room below. | Quieter. The mass of the glass and the sealed air gap kill most of it. |
| Heat and cold | Single or double skin plastic. It is the weak spot in the roof in January and in July. | Insulated glass, low-E coating, warm-edge spacer. Considerably better. |
| Warranty | Manufacturer warranty on the dome itself. | Factory seal warranty on the insulated unit, plus our 10-Year No Leak Warranty on the installation. |
| Weight and span | Light. Covers a big opening without heavy framing, which is why old buildings have them. | Heavier. A very large opening becomes a bank of units or a structural assembly. |
| Impact | Hard to break, easy to scratch and to crack once it has gone brittle with age. | Tempered outer, laminated inner on most units. Harder to scratch. |
| Where it wins | Large commercial and industrial roofs, big spans, matching an existing run of domes, and a tight budget on a roof nobody looks at. | Anywhere a person is underneath it looking up: kitchens, stair halls, baths, rear extensions, offices. |
This is the part that decides whether your new dome lasts twenty years or two, and almost nobody checks it before quoting.
An acrylic dome sits on a curb, a raised box framed up off the roof deck, and the curb is tied into the roof with flashing. On most New York buildings the dome has been changed once or twice and the curb never has. It is original. It has been wet on and off for decades and the top of it is soft.
When water is coming in, the dome itself is rarely the reason. The dome is just the part you can see. It is the curb, the flashing, or the seam where the flashing meets the roof membrane. Put a shiny new dome on that and the leak carries on exactly as before, only now you have paid for it and you believe the problem is solved.
So we look first, and we tell you which of the two situations you are in:
| What we find | What we quote |
|---|---|
| Curb sound, flashing sound, dome cracked, crazed or yellowed | A straight swap. New acrylic dome, or a glass unit on the same curb — your choice, priced both ways. |
| Curb soft or rotted at the top, flashing lifting, membrane failed at the seam | Curb rebuilt and reflashed, then the new unit. Costs more on the day and it is the only version that stops the water. |
| Curb too low for a flat roof, unit sitting in standing water | The curb gets raised. Curb height is a large part of why flat-roof skylights fail in this city. |
| Dome fine, water coming from somewhere else on the roof | We tell you that and we do not sell you a skylight. |
Our labor is published and it does not change with the material. Standard replacement labor on a sound existing curb is $1,585. Rebuilding a rotted curb, raising a curb, or cutting a new opening is quoted after the free site visit, because guessing at it in a phone call is how people end up with a number that moves later.
On the unit itself, here is where we can and cannot publish a figure. Our glass line is a fixed price list and it is on this site. Acrylic domes are priced off the VELUX dome book by size, and there are dozens of sizes, so we price yours the day you send the measurement rather than putting a fake range on a web page.
Those glass numbers matter here even if you think you want a dome, because they are usually lower than people expect. This is what a glass unit costs installed on a curb that is still sound, unit price including New York City sales tax with the factory solar shade and the remote:
| On your existing curb | Unit incl. NYC tax | Labor | Installed |
|---|---|---|---|
| Fixed glass, flat roof curb-mount | $474 | $1,585 | $2,059 |
| Manual venting glass | $983 | $1,585 | $2,568 |
| Solar venting glass, remote and rain sensor | $1,890 | $1,585 | $3,475 |
| Acrylic dome, any size | Priced off the VELUX dome book | $1,585 | Quoted the day you send the size |
| New opening cut and framed where there is none | Includes flashing and interior finish | from $2,900 | |
We are not trying to talk everybody into glass. There are jobs where the dome is simply correct and we say so:
Big commercial and industrial roofs. Warehouses, garages, factory floors and back-of-house spaces where the opening is large, nobody is looking up at it, and daylight is the entire point. Acrylic covers a big span cheaply and the weight saving is real.
Matching an existing run. If you have eight domes across a roof and two have failed, putting glass in those two makes the roof look wrong and costs more than it is worth. We match.
Very large single openings. Past a certain size, glass stops being one unit and becomes a bank or a structural assembly with framing. A dome stays one piece.
Budget on a roof nobody sees. A rear shed, a garage, a utility room. If the money is better spent elsewhere on the building we will tell you that.
And where an old dome is simply doing its job, we say to leave it alone. Free assessment either way, and it is free whether you buy anything or not.
Our shop is on Gerritsen Ave in Brooklyn and flat-roof domes are one of the most common things we are called out to. Park Slope, Carroll Gardens, Cobble Hill, Boerum Hill, Fort Greene, Clinton Hill, Prospect Heights, Bed-Stuy, Crown Heights, Windsor Terrace, Ditmas Park, Flatbush, Sunset Park, Bay Ridge, Dyker Heights, Bensonhurst, Sheepshead Bay, Marine Park, Mill Basin, Canarsie, Gerritsen Beach and Red Hook. Also across Queens, Manhattan, the Bronx, Staten Island, Long Island and Westchester — and on the commercial side, wherever the roof is. Estimates are free everywhere we go.
Yes, when the curb and the flashing under it are sound. That is a real repair and we price it. We check the curb first, every time, because on most New York buildings the dome has been changed once or twice and the century-old curb underneath never has. If the curb or the flashing is what actually failed, a new dome by itself will not stop the water and we will tell you that before you spend the money.
We install both and we will price both, so it is your call. If the room below is lived in we point people toward glass: it stays clear where acrylic yellows and hazes, it is much quieter in heavy rain, it insulates far better, and it carries a factory seal warranty. If the roof is commercial, the span is large, or you are matching an existing run of domes, the dome is the right answer and we say so.
Our labor is published and does not change with the material: $1,585 standard replacement labor on a curb that is still sound. The dome itself is priced off the VELUX dome book by size, so we quote it the day you send the measurement rather than publishing a made-up range. For comparison, a fixed glass unit on the same sound curb is $2,059 installed, including New York City sales tax, the factory solar shade and the remote.
Ultraviolet light. Acrylic yellows and hazes under years of direct sun, and a New York flat roof has no shade on it at all. Once it has discoloured the light coming into the room goes flat and grey, and the plastic has usually gone brittle at the same time, which is where the hairline cracks start. It is not dirt and it does not clean off.
Sometimes, and less often than people assume. A cracked dome does let water in, but on the majority of the leaks we are called to the dome is intact and the water is coming through the flashing, the seam where the flashing meets the roof membrane, or a curb that has gone soft. That is why we look at the whole opening before quoting instead of pricing a dome over the phone.
Usually yes, and it is one of the cheapest upgrades on a building. If the curb is sound and the opening is a size the glass line covers, we take the dome off and set a curb-mounted glass unit on the same curb with new flashing. No cutting, no framing, no interior work. We confirm the curb dimensions on the site visit before anything is ordered.
Yes, and it is where domes make the most sense. Warehouse and factory roofs, garages, back-of-house spaces, whole runs of units replaced across one roof. Large spans, daylight as the point, nobody looking up at it. We also supply the units alone to roofers and general contractors if you have your own crew.
It depends on the work. Replacing a unit inside an existing opening is treated differently from cutting or reframing the roof deck, and commercial buildings and landmark districts add their own requirements. We have been filing this work in the city since 2005 and we will tell you which category your job is in before you commit to anything. Our page on NYC permits and landmark rules walks through it.
Yes. Supply only is open to homeowners, roofers and general contractors. We spec the unit, confirm the size against your curb before anything is ordered, and deliver to the job. The one thing to know is that our 10-Year No Leak Warranty covers our installation, so it does not follow a unit that somebody else puts in.