Mercer County, New Jersey
Roofing across Mercer County,
town by town
Mercer County has the oldest houses we work on. The average home on the county tax list dates from 1956, a full seventeen years older than Somerset, and in Trenton the average is 1913. That changes the job. Older roofs carry more layers, more chimneys, more low slope porch and addition roofs, and more flashing that has been patched rather than rebuilt. It also makes Mercer the county where insurers ask about roof age most often.
12 municipalities · Licensed and insured NJ contractor · Written photo report with every inspection
Our Mercer County towns
We have a page for each of these, with what we actually see on roofs there. Princeton, West Windsor, Hamilton Township and East Windsor — and we cover the rest of the county too.
Princeton
6,826 homes · average 1958
The oldest housing we work on, under the heaviest tree cover. Historic district rules apply in parts of town.
Roofing in Princeton →
West Windsor
7,672 homes · average 1985
Flat, open and built for commuters since the 1970s. Wind has a clear run, and the Millstone corridor floods.
Roofing in West Windsor →
Hamilton Township
29,380 homes · average 1960
Not one town but a dozen villages grown together: Mercerville, Hamilton Square, Yardville, Groveville and White Horse.
Roofing in Hamilton Township →
East Windsor
7,752 homes · average 1979
Split levels from the 1950s and 60s, then Twin Rivers in 1970 — the first planned community in New Jersey.
Roofing in East Windsor →
What roofs are like in Mercer County
There are 106,118 homes on the county tax list with a recorded build year, and the average one dates from 1956. Ninety two percent were built more than twenty five years ago, sixty eight percent before 1980, and a third of the entire county predates 1950 — thirty six thousand homes. Six percent were built before 1900. Only eleven percent has gone up since 2000, almost all of it at the Windsors and the Lawrence and Hopewell edges.
The county runs from the Delaware at Trenton across to the flat open farmland either side of Turnpike exit 8. Those two ends are nothing alike. Trenton, Hamilton and Ewing are the dense older core, built close together with mature street trees. East and West Windsor are open country with far less canopy, and on flat ground with little shelter a nor easter gets a clean run at a roof edge. Princeton sits between them with heavy mature cover and a lot of houses old enough to have been reroofed several times already.
The thing to understand about Mercer is layers. On a house from the 1920s or 1950s the roof has usually been done more than once, and what is underneath decides what the job really costs. A single layer over good decking is straightforward. Two or three layers, old flashing tarred rather than replaced, and a chimney that has never been properly stepped in is a different piece of work. Nobody can tell you which one you have from the street, which is the honest reason the inspection exists.
What we do across Mercer County
Mercer calls us about leaks more than about replacement, and usually at a flashing joint rather than in the middle of a slope. That is the age of the stock talking. The inspection tells you whether it is a repair or whether the covering has genuinely run out.
Roof repair
Leaks traced to where the water really gets in, flashing rebuilt, and an honest repair or replace answer.
Free roof inspection
A written report with photos and one straight answer: repair it, replace it, or leave it alone.
Roof replacement
Full tear off, new underlayment and flashing, itemised quote you can compare line by line.
Insurance and certification
Roof condition reports for carriers reviewing your policy at renewal, documented properly.
Wind and storm damage
After a nor easter: what moved, what is actually damaged, and what a claim would really involve.
Skylight installation
VELUX units fitted as part of the roof system, because that flashing joint is where leaks begin.
Signs a Mercer County roof needs a look
On an older Trenton, Hamilton or Ewing street
- A layover covering laid straight on top of the last one
- Flashing at the chimney patched with tar rather than replaced
- Staining on a ceiling below a low slope porch or addition roof
- Ice dam marks along the eaves after a hard winter
Out at the Windsors, on flat open ground
- Shingles lifted along a roof edge after a nor easter
- Ridge caps curling on a roof with nothing sheltering it
- Granules collecting at the bottom of the downspouts
- A whole street of the same phase reaching the same age together
Anywhere a carrier has started asking questions
- A renewal letter asking the age of the roof
- A request for photographs or a condition report
- A policy moved from replacement cost to actual cash value
- An inspection booked by the insurer without warning
Mercer County roofing questions
Which Mercer County towns do you cover?
We have pages for Princeton, West Windsor, Hamilton and East Windsor, and we work across the rest of the county as well, including Lawrence, Ewing, Hopewell, Pennington and Trenton. Call and tell us the street.
My address says Princeton but I am told I am not in Princeton. What is going on?
The 08540 mailing ZIP reaches well beyond the municipality of Princeton, into southern Franklin Township in Somerset County and out toward Montgomery. A Princeton mailing address is not proof of being in Princeton, or even in Mercer County. It makes no difference to the roof, and quite a lot of difference to insurance and permit paperwork, so it is worth being clear which municipality you are actually in before anything is filed.
Is this the same Hamilton Township people get confused about?
Yes. Hamilton Township in Mercer County is a different municipality from the Hamilton Township in Atlantic County near Atlantic City, and several Mercer Hamilton addresses carry Trenton mailing ZIPs on top of that. It is a routine source of confusion with insurers and with contractors quoting from a map rather than a visit.
Do you charge more to come out to the far side of Mercer County?
No. The inspection is free anywhere we work, and the quote is for the roof, not for the drive. If you are far enough out that we could not look after the job properly we will tell you that on the phone rather than take it and stretch a crew.
Is the roof inspection really free?
Yes. We look at the roof, photograph what we find, and give you a written assessment at no cost. You decide what happens next. There is no obligation and nobody will lean on you to book work.
Will you tell me if my roof does not need replacing?
Yes, and it happens often. Plenty of roofs called finished can be repaired and go on for years. If a repair is the smarter move that is what we put in writing, even though it is the smaller job for us.
My insurer wrote to me about the age of my roof. Can you help?
Yes. New Jersey carriers have been reviewing roof age at renewal and asking for evidence of condition. We provide a photo documented roof condition report you can send them. A good number of age related worries end there, or with a targeted repair, rather than a full replacement.
Do I need a permit to replace my roof?
Usually not, and this surprises people. Since March 2018 a plain shingle replacement on a one or two family home counts as ordinary maintenance across New Jersey, so no permit is required. Structural work, a change of roof type, or anything beyond the covering is different, and we tell you which one you are looking at before the job starts.
The housing numbers for Mercer County
- Homes
- 106,118
- Average year built
- 1956
- Built over 25 years ago
- 92%
- Built before 1980
- 68%
Read that carefully, because at county scale it is even easier to misuse. These figures describe the age of the houses in Mercer County, not the age of the roofs on them. A great many of these homes are on their second or third covering, and a house from 1956 may well be carrying a roof from 2015. No tax record anywhere says when a roof was last done, and anyone quoting you off a build year is guessing.
What the numbers do tell you is where roof age is worth checking. In a county where most homes are past twenty five years, the chance that yours is due is simply higher, and twenty five years is roughly when New Jersey carriers started asking for a roof condition report before renewing a policy.
The largest municipalities in the county
- Hamilton
- 29,388 homes · average 1960
- Trenton
- 20,737 homes · average 1913
- Ewing
- 10,669 homes · average 1959
- Lawrence
- 10,023 homes · average 1972
Source: New Jersey MOD-IV property tax list, residential parcels with a recorded build year, read September 2026. Aggregate counts only.
The other counties we cover
Our Certifications
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Roof work anywhere in Mercer County
A free inspection, a written report with photos, and a clear recommendation. Tell us the street and we will tell you which of our two offices is closer.