The Private Road Reserve Rate
Our letters to associations that own their streets estimate what it costs to keep that pavement up: $0.20 per square foot a year. This page shows where that number comes from, so it can be checked rather than taken on trust.
Why a rate, and not your budget
Every association’s reserve study is different, and we have not seen yours. A rate lets us price every private road in Niwot the same way, from the one thing we can measure for all of them: the square feet of pavement. If your association has a current reserve study, its road line is a better number than ours for your streets. Use it.
The derivation
A reserve study sets money aside for asphalt in two pieces: the periodic mill and overlay that resurfaces the road, and the seal coat applied between overlays to protect it. The annual amount for each is its cost divided by how many years it lasts.
| Component | Cost per sq ft | How often | Per sq ft per year |
|---|---|---|---|
| Mill and overlay, 2″ | $2.44 | every 20 years | $0.122 |
| Seal coat | $0.23 | every 3 years | $0.077 |
| Total | $0.199 → $0.20 |
- Overlay cost, $2.44 per square foot. The committee’s road cost model: the delivered contractor rate, with overhead, in 2024 dollars. It is the same rate used for every road in Niwot in the roads paper.
- Overlay life, 20 years. The low end of the 20 to 27 years that Countryside Condominiums’ 2021 reserve study (Aspen Reserve Specialties) gives for asphalt that is maintained on a regular schedule. It is the only reserve study for a Niwot private road that we have.
- Seal coat, $0.23 per square foot every 3 years. From the same study: $24,312 in 2026 for its 105,865 square feet of asphalt, with a three-year life.
Checked against the study itself
Countryside’s study recommends $6,960 a year toward its overlay and $6,888 toward seal coat: $13,848 over 105,865 square feet, or about $0.13 per square foot in 2021 dollars. Our rate is higher for two reasons, both stated here. We use a current delivered overlay price ($2.44, against the study’s 2021 estimate of $1.65 to $1.90). And we use a 20-year life instead of 27. At 27 years, our rate would be $0.17.
What it leaves out
Everything below would make the figure larger, not smaller:
- Crack filling and pothole repair, which Countryside’s study treats as an annual operating expense rather than a reserve item.
- Concrete curb and gutter. Countryside reserves about $2,000 a year for it, roughly two cents a square foot.
- Snow removal.
- Full reconstruction, which our road cost model prices at $5.67 per square foot once a road is allowed to fail.
How the letters use it
Each letter multiplies the rate by its association’s street area and divides by the number of homes. The street area is travel lanes only, not parking lots or driveways. A 13-home association with 50,582 square feet of street comes to about $10,100 a year, or $778 a home. That is the cost the town would take on if the association agreed to transfer its roads. It is an estimate of what the association should be reserving, not a statement of what it collects in dues.
The derivation is reproduced by working/roads-cost-model/hoa-reserve-studies/reserve_rate.py, which fails if the letters use a different rate. Questions to contact@niwot.town.