Defensible-space work in the WUI: what the contracts require and what your policy has to say

The honest answer is that defensible-space work is landscaping and tree work and land clearing at the same time, done inside 100 feet of somebody’s house, in the part of Colorado most likely to burn. The contracts know it. A fire district’s mitigation program, an HOA’s fuel-reduction bid, and a homeowner’s cost-share job through the state forest service all arrive with an insurance exhibit, and the exhibit asks for more than a lawn-care policy carries. We write landscaping insurance in Colorado and we thin lodgepole above Bailey ourselves, so here’s who writes these contracts, what they ask for, and what your policy has to be able to answer.

Who’s on the other side of the contract

Five kinds of clients, and the paperwork gets heavier as you go down the list.

The homeowner. A cabin owner in Summit County whose insurance carrier sent a letter about the trees. Often no written contract at all, which is its own problem. Ask for one.

The HOA. Common in the mountain subdivisions around Breckenridge, Vail, and Bailey. The board has a template that asks for the association and the management outfit as additional insureds, plus a hold-harmless clause somebody’s attorney wrote for a different trade.

The fire protection district. Community mitigation programs, chipping days, roadside fuel breaks. Public-body contracts, with a public-body insurance exhibit and sometimes a bond.

The county or state program. Cost-share and grant-funded work, where the county or the Colorado State Forest Service sets the spec and the insurance minimums come with the funding.

Federal and state land. Stewardship contracts and fuel-reduction task orders on Forest Service and state land, with their own forms, their own fire-plan requirements, and their own way of counting acres.

The thing they share: they are all written by someone who has watched a mitigation job start a fire, and the exhibit reflects it.

The zones the scope comes from

Every defensible-space scope you’ll see is built on the same map.

That last part is the point. Ten years ago a lot of this was a handshake and a chainsaw. Now the same job in Eagle County can run through a permit, a plan review, and a contract exhibit that reads like a commercial GC’s.

What the exhibit typically asks for

Line by line, the pattern in this trade.

Two lines that aren’t always on the exhibit but decide the claim: pollution (chainsaw fuel, bar oil, and a tipped fuel can on a slope above a creek are typically excluded under most standard GL forms) and equipment (the tracked mulcher and the chipper are your own property and not a GL claim on any form).

What your policy has to say

The exhibit tells you what to carry. What matters more is what the policy does when a mitigation job goes wrong, and there are four ways it does.

Fire. The crew’s mulcher or a saw starts a fire that runs to the neighbor’s land. Under most standard forms the neighbor’s damage and the district’s suppression bill typically come to your general liability, subject to the limits. Multiple neighbors in a WUI subdivision are one occurrence with a lot of claimants, which is where a $1M limit gets tested and the umbrella matters.

The tree. A leaning lodgepole felled inside Zone 2 that lands on the deck, the propane tank, or the neighbor’s roof. Property damage to a third party, GL again, and the reason tree work is rated the way it is. If the crew climbs, rigs, or uses a bucket, the payroll typically rates as tree work rather than landscaping, and a policy that doesn’t know the crew climbs is a policy with an argument in it.

The crew. A climber, a saw operator, or a laborer dragging slash on a 30 percent slope of decomposed granite. Workers’ comp, and Colorado’s test for who counts as an employee is not the tax form. The 1099 climber you direct on site is generally your employee for comp purposes, and the uninsured sub article explains what happens when the sub you hired for the felling has no comp of his own.

The line. A fuel break cut past the survey stake onto the parcel next door, or the wrong trees thinned on a lot with an HOA landscape covenant. A GL claim with a trespass argument attached, and the scope drawing in the contract is the exhibit that decides it.

Three local codes worth knowing before you bid

The WUI codes are about hardening buildings, not about how you thin. But they’re why the contracts exist, and the local versions differ.

Vail. Vail's wildland-urban interface standards add Chapter 7A (Fire Resistive Construction) requiring non-combustible or ignition-resistant exterior wall coverings, decking, eaves, soffits, doors, and vents, and require ignition-resistant landscaping under Title 14 from the building drip edge out to 100 feet or the property line, whichever is less. (Town of Vail, Wildland Urban Interface Building, Planning and Development Standards Summary; Vail Town Code Ch. 7A; Title 14) A landscape crew working in Vail and Eagle County is working to that standard whether the contract says so or not, and plan review will read your scope against it.

Summit County. Summit County applies the Colorado Wildfire Resiliency Code to building permits applied for after May 4, 2026, and treats all areas of the county, including town centers, as moderate to high fire intensity requiring Class 2 structure hardening. (Summit County Building Inspection, Wildfire Resiliency) That page is about the structure. What it tells a contractor in Summit County is that any job tied to a building permit after that date sits under the new code, and the defensible-space scope that goes with the permit will be written to match.

Routt County. Routt County jurisdictions adopted four sections of the 2021 International Wildland-Urban Interface Code effective January 1, 2024, covering wildfire-protective roof assemblies, roof valley flashing, noncombustible gutters and downspouts, and vents screened to one-quarter inch, for new construction, additions, alterations, repairs, and replacements. (Steamboat Pilot, "Several wildfire resilient building codes start Jan. 1" (2021 IWUIC sections adopted by Routt County Regional Building Department)) [VERIFY] That one carries a verify badge because we’ve only seen the newspaper account, not the adopted ordinance, so confirm it with the Routt County Regional Building Department before relying on any of it. The four sections we’ve seen described are roof and vent provisions, which don’t touch vegetation work, but a Steamboat contractor bidding mitigation on a new build should ask what else was adopted.

We don’t know what every county has adopted since the state board’s deadline, and we’re not going to pretend we do. Ask the building department and the fire district which code applies to the lot, and get the answer in the contract.

Where to go from here

If you’re bidding defensible-space work this season, send us the exhibit before you sign it. The GC requirements article shows how to read one without an attorney, and most mitigation exhibits follow the same shape. Starting fresh? Get Insured lists what to have ready, and the first questions we ask a mitigation contractor are whether the crew climbs, what’s on the mulcher to put a fire out, and how close to the house the work runs. No online quote, on purpose.

Serving businesses located in Colorado. Coverage is determined by the policy language and the carrier.