Portsmouth is the New Hampshire seacoast's premium market: a small, in-demand contractor pool, a large historic-district footprint, and no sales tax on materials. Labor runs above the state average and the best crews book seasons ahead.
Our Haus isn't a contractor directory. We give you the local cost math, the permit reality, and the paperwork tools — the scope, the proposal comparison, and the vault your records live in.
Based on a 1,800 sq ft siding replacement scope, adjusted by the New Hampshire regional cost index and a Portsmouth metro multiplier of 1.05×. A 10% contingency reserve is included. These are budgeting estimates, not quotes.
| Portsmouth siding replacement | Low | Likely | High |
|---|---|---|---|
| Basic finishEntry-level materials, no layout change | $45k | $80k | $125k |
| Mid-range finishThe most common scope | $80k | $134k | $214k |
| High-end finishCustom materials and detail | $214k | $321k | $491k |
Source: Our Haus cost engine — per-square-foot bands from public industry data (Cost vs. Value, NAHB, RSMeans-derived regional indices), adjusted for New Hampshire and the Portsmouth metro.
Estimated range — based on BLS OEWS national average wages and BLS PPI material indexes applied to Our Haus baseline unit costs, as of June 2026. Estimates are shown as a range and help set expectations. They are not a quote, a verified price, or an appraisal of what a contractor will charge.
| Line item | Low | Likely | High |
|---|---|---|---|
| Decking / paving materials | $23k | $39k | $62k |
| Structural framing | $13k | $22k | $35k |
| Railings & stairs | $7.3k | $12k | $19k |
| Footings | $7.3k | $12k | $19k |
| Labor | $19k | $32k | $51k |
| Permits | $2.9k | $4.9k | $7.8k |
Estimated range — based on BLS OEWS national average wages and BLS PPI material indexes applied to Our Haus baseline unit costs, as of June 2026. Estimates are shown as a range and help set expectations. They are not a quote, a verified price, or an appraisal of what a contractor will charge.
One of the densest stocks of 18th- and early-19th-century housing in the country downtown, with early-1900s neighborhoods beyond and post-war capes toward the edges. Pre-1900 work routinely involves timber framing, rubble foundations, and preservation-review constraints.
Common Portsmouth neighborhoods where this work comes up: Downtown, South End, Little Harbor, Atlantic Heights, Elwyn Park.
Authority: City of Portsmouth Inspection Department
Building permit plus trade permits pulled by licensed trades. Much of the city falls inside the Historic District, where exterior changes require Historic District Commission approval before the building permit issues — plan that review into the schedule.
New Hampshire does not license general contractors at the state level, so verification falls on the homeowner: confirm liability and workers' compensation coverage directly with the insurer, and confirm current state licenses for electricians and plumbers. With no statutory written-contract threshold, a written scope, payment schedule, and change-order clause matter more here, not less.
Coastal weather allows a slightly longer exterior season than inland, but salt air shortens exterior finish life. Historic-district review adds lead time in any season — winter is the time to design and permit, spring to build.
Typical duration: 1–3 weeks on site for a typical single-family.
Wall area, openings, and a teardown assessment of the existing cladding layers.
Fiber cement and special-order colors carry lead times; confirm before teardown.
Old siding off, sheathing inspected, repairs at the stated unit price.
The phase that decides whether the job lasts. Housewrap, tapes, pan flashing at openings.
Product installation with proper clearances at roofs, decks, and grade.
Siding is a weather-barrier job wearing a cosmetic costume. The product line on the bid matters less than the flashing, housewrap, and window-integration details underneath — and those are exactly the lines that disappear from the cheapest quote.
Full checklist: what should be in a contractor's estimate.
We don't keep a contractor directory, and we won't pretend to. The dependable process is to gather two or three referrals locally, check the New Hampshire registration or license rules above, confirm general liability and workers' compensation directly with each carrier, then compare the written proposals side by side against the ranges on this page.
Run a Portsmouth contractor's business? You can publish a free Our Haus profile with your license, insurance dates, service area, and work photos, and share it by link or QR code.
Run it through the quote range checker. We compare it against the New Hampshire cost index, flag line items that look high, and review the contract against New Hampshire home-improvement rules.
Check my quoteSometimes — over one sound layer of flat siding, with the right preparation, it is legal and can be reasonable. Over multiple layers, over rot, or where window flanges need re-flashing, strip it. Any honest answer requires looking at what is on the house now.
Quality vinyl and fiber cement are routinely rated for decades, and both handle freeze-thaw well when the weather barrier underneath is detailed correctly. Cedar performs beautifully but wants a maintenance cycle. The failure mode in New England is almost never the product — it is the flashing.