How much defensible space do I need in Colorado?

The Colorado State Forest Service recommends a minimum of 100 feet of defensible space around a home, and more on steep slopes or in heavy fuels. It is organized into zones: Zone 0 (0–5 ft, noncombustible), Zone 1 (5–30 ft, lean and clean), Zone 2 (30–100 ft, reduced fuel) and Zone 3 (100 ft+, forest management on larger properties).

What is the most effective way to protect a home from wildfire?

Research consistently shows the single most effective step is hardening the home and the first five feet around it against embers, because most homes ignite from wind-blown embers, not the flaming front. Combine that ember-resistant zone with defensible space out to 100 feet and ongoing maintenance for the best protection.

The Complete Homeowner's Guide · 2026

How to mitigate fire risk in Colorado

Q: How do I mitigate fire risk in Colorado?

Mitigating wildfire risk in Colorado rests on three pillars: (1) create defensible space by removing and thinning vegetation in zones around your home, (2) harden the home itself with a Class A roof, ember-resistant vents, and a noncombustible 0–5 foot zone, and (3) maintain it every season. Start by checking your wildfire risk score, then complete and document the work for the state tax credit, grants and insurance.

Q: How close can trees be to a house for fire mitigation?

Keep the first 5 feet around your home (Zone 0) free of trees, shrubs and combustible mulch entirely. From 5 to 30 feet, individual tree crowns should be spaced at least 10 feet apart and at least 10 feet from the structure, with no branches overhanging the roof or within 10 feet of the chimney. On slopes, increase that spacing, steeper ground needs 20 to 30+ feet between crowns. Remove all dead, diseased and beetle-killed trees regardless of distance.

Q: Where are defensible space Zones 1, 2 and 3 located?

Zone 1 is the 5–30 foot band closest to the home (some guidance starts it at the wall and adds a 0–5 ft Zone 0). Zone 2 is 30–100 feet from the home. Zone 3 is everything beyond 100 feet, relevant on larger lots and acreage. Distances are measured outward from the structure and should be extended farther downslope because fire moves faster uphill.

Q: How do I make a moisture map for fire mitigation?

Sketch your property with the home at the center and the defensible-space zones marked out to 100+ feet. Color-code it: green for irrigated, high-moisture areas you keep watered near the home (these act as fuel breaks), and red for dry, high-fuel hotspots like cured grass, dead vegetation, woodpiles and slash. Track seasonal dryness using live fuel moisture and drought data from the Colorado State Forest Service and National Weather Service, then plan irrigation and thinning so the area nearest the home stays green and the outer zones stay thinned.

Q: Is fire mitigation tax deductible in Colorado?

Colorado offers a wildfire mitigation income tax credit equal to 25% of qualifying defensible-space and fuels-reduction costs, up to $625 per year (subject to income limits), and CSFS grants and Wildfire Partners rebates may offset more. Keep itemized invoices and before/after photos to claim them.

Everything a Colorado homeowner needs to protect their home and family from wildfire, defensible space zones, how close trees can be to your house, home hardening, firewise landscaping, a property moisture map, costs and funding. Plain-English, science-based, and built on Colorado State Forest Service and NFPA guidance.

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Start here

Fire mitigation, in three pillars

Protecting a home in Colorado's wildland-urban interface comes down to three things: defensible space (managing the vegetation around the home), home hardening (making the structure itself ember-resistant), and maintenance (keeping it up every season). This guide walks through all three, and answers the specific questions homeowners ask most.

🔥 What is fire mitigation? 📐 Defensible space zones 🌲 How close can trees be? 🏠 Home hardening 🪴 Firewise plants 💧 Make a moisture map 🗓️ Seasonal checklist 💵 Cost & funding ❓ FAQ

The basics

What is fire mitigation, and why embers matter most

Fire mitigation is the work of reducing the flammable vegetation (fuel) around a property and hardening the structure so an approaching wildfire has less to burn and is far less likely to ignite your home. In Colorado that means defensible space, tree thinning, brush and ladder-fuel removal, and home hardening.

Here's the key insight that should shape every decision: most homes that burn in a wildfire don't ignite from the wall of flame. They ignite hours before or after, from wind-blown embers that land in dry needles on the roof, in gutters, in mulch beds against the siding, or in a woodpile on the deck. That's why the first five feet around your home matter more than anything else, and why mitigation works even when a fire is intense.

Wind-driven embers igniting fuels around a Colorado home

Defensible space

The defensible space zones, explained

Colorado's defensible space is built outward from your walls. The Colorado State Forest Service recommends a minimum of 100 feet, more on slopes. Here's what each zone is and where it's located.

Zone 0, Immediate (0–5 ft)

The single most important zone: the noncombustible, ember-resistant five feet right against the structure.

No wood mulch, shrubs, or stored items against siding, use gravel, pavers or bare soil
Nothing flammable under decks, stairs or attached fences
Keep needles and leaf litter off the roof and out of gutters

Zone 1, Lean & Clean (5–30 ft)

The most carefully managed living area. The goal is well-spaced, low-flammability plants and no continuous path of fuel to the home.

Tree crowns spaced at least 10 ft apart; none overhanging the roof
Limb trees up 6–10 ft from the ground to break "ladder fuels"
Relocate woodpiles and propane tanks out of the zone

A crew clearing ladder fuels near a home

Zone 2, Reduced Fuel (30–100 ft)

A thinned, broken-up landscape designed to drop a crown fire to the ground and slow its spread before it reaches the home.

Thin stands to firewise crown spacing (wider on slopes)
Break up continuous scrub and Gambel oak thickets
Mow grasses to 4 inches and remove surface litter

Zone 3, Extended (100 ft+)

On larger lots and acreage, light ongoing forest management that improves overall forest health and resilience.

Selective thinning of overcrowded stands
Slash chipping or forestry mulching
Slope-adjusted treatment, extend zones farther downhill

Forestry crew managing fuels on a Colorado hillside

Slope matters: fire moves faster uphill, so on steep ground extend each zone farther downslope of the home and widen tree spacing. A property on a 20%+ slope may need defensible space well beyond 100 feet. Read our deeper defensible space zones guide.

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Tree spacing

How close can trees be to a house?

One of the most common questions, and one of the most important. The short answer: keep the first 5 feet tree-free, keep crowns at least 10 feet from the home and from each other, and never let branches overhang the roof. Here's the full breakdown:

Distance from home	Tree & vegetation rule
0–5 ft (Zone 0)	No trees or shrubs at all. Noncombustible surfaces only (gravel, pavers, bare soil).
5–30 ft (Zone 1)	Individual trees only, well separated. Crowns at least 10 ft apart and 10 ft from the structure. No branches within 10 ft of the roof or chimney. Limb up 6–10 ft.
30–100 ft (Zone 2)	Small clumps allowed; keep 10 ft between crowns on flat ground. Remove ladder fuels and dead material.
On slopes	Increase spacing to 20–30+ ft between crowns as the grade steepens, and extend treatment downhill.
Any distance	Remove all dead, diseased and beetle-killed trees, and any tree touching or overhanging the house, deck or power lines.

Rule of thumb: picture each mature tree's crown with a 10-foot bubble around it that shouldn't touch the house, the next tree's bubble, or a continuous line of brush. Breaking that continuity is what stops fire from "laddering" up and crowning toward your roof.

Home hardening

How to build a fire-resistant home

Defensible space buys your home a chance; home hardening is what actually keeps embers from finding a way in. These are the highest-impact upgrades.

Class A roof & clean gutters

A Class A fire-rated roof and metal gutter guards stop the #1 ember trap, accumulated needles and leaves.

Ember-resistant vents

Cover or replace attic and crawlspace vents with 1/8-inch metal mesh (or listed ember-resistant vents).

Decks & the 0–5 ft zone

Use noncombustible decking or skirting, and keep nothing flammable under or within 5 feet of the deck and walls.

Dual-pane & tempered windows

Multi-pane windows resist breaking from radiant heat, which keeps embers from entering when glass fails.

Ignition-resistant siding

Stucco, fiber-cement or other noncombustible siding resists direct flame and radiant heat far better than wood.

Fence & gate connections

A wood fence is a wick straight to your house, use a metal gate or noncombustible section where a fence meets the home.

See the full service: home hardening in Colorado.

Firewise landscaping

Fire-resistant plants & landscaping

No plant is "fireproof," but moisture-rich, low-resin, well-maintained plants resist ignition. The principle that matters most is placement and spacing, not just species.

Lower-flammability choices

Well-watered, deciduous trees (aspen, maple) over resinous conifers near the home
Succulents and high-moisture groundcovers (hens-and-chicks, ice plant)
Mowed, irrigated turf or native short grass in Zone 1
Perennials and herbaceous plants kept green and trimmed

Avoid near the home

Junipers, arborvitae and other resin-heavy evergreens (notorious "gasoline plants")
Ornamental grasses that cure to tinder by late summer
Bark/wood mulch in the 0–5 ft zone, use rock instead
Dense, unmaintained shrubs touching the siding

A pro technique

How to make a moisture map for your property

A "moisture map" is a simple sketch of your property color-coded by how wet or dry each area is, a powerful planning tool, because green, irrigated areas act as fuel breaks and dry, cured vegetation is where fire accelerates. Here's how to make one:

1

Sketch the property

Draw your home at the center with the defensible-space zones (5, 30, 100 ft) ringed around it. Mark slopes and prevailing wind direction.

2

Mark green zones

In green, shade the irrigated, high-moisture areas you actively water, lawn, garden beds, succulents, especially within 30 ft of the home. These are your built-in fuel breaks.

3

Flag the dry hotspots

In red, mark dry fuel: cured grass, dead or beetle-killed trees, brush thickets, woodpiles, slash and propane tanks. These are your priority work areas.

4

Track & act seasonally

Use Colorado live fuel-moisture and drought data through the season; expand irrigation and thinning so the near-home zone stays green and the outer zones stay thinned and clean.

Data sources: the Colorado State Forest Service and National Weather Service publish live fuel-moisture and fire-danger updates, and the U.S. Drought Monitor shows seasonal dryness. Together they tell you when your landscape is curing out, and when to be most ready. Want it done for you? Our wildfire risk assessment maps your property's fuels and moisture professionally.

Keep it up

Seasonal fire-mitigation checklist

Mitigation isn't one-and-done, fuels regrow and litter accumulates. Work this rhythm every year:

Spring (snowmelt – June)

Clear winter-downed branches and dead vegetation. Remove needles and leaves from the roof, gutters, decks and the 0–5 ft zone. Mow grasses early before they cure. Schedule any tree thinning or mulching before fire restrictions begin.

Summer (peak fire season)

Keep grass mowed to 4 inches, irrigate green zones, and re-clear needles after windstorms. Move anything flammable off decks. Confirm your address is in your county alert system and review your evacuation plan.

Fall

Final cleanup of fallen leaves and needles, especially on the roof and in gutters. Stack firewood at least 30 feet from the home. Address any hazard trees before winter snow load.

Year-round

Remove dead/beetle-killed trees promptly, keep the 0–5 ft zone noncombustible, and re-photograph your work for your insurance and tax-credit file.

Set up wildfire alerts →

What it costs, and who helps pay

Cost & funding for Colorado fire mitigation

Typical project

$1.5k–8k

Most residential defensible-space projects, by lot size, slope & density.

CO tax credit

25%

of qualifying costs back, up to $625/yr (income limits apply).

CSFS grants

Grants

Cost-share for communities, HOAs, fire districts & partnerships.

Insurance

Discounts

Documented mitigation increasingly required or rewarded by insurers.

See funding & insurance options Full cost breakdown Tax credit guide

Also see: Colorado wildfire grants

FAQ

Colorado fire mitigation questions

How do I mitigate fire risk in Colorado?

Three pillars: create defensible space (thin and clear vegetation in zones around the home), harden the home (Class A roof, ember-resistant vents, noncombustible 0–5 ft zone), and maintain it every season. Start by checking your wildfire risk score, then document the work for the state tax credit, grants and insurance.

How close can trees be to a house for fire mitigation?

Keep the first 5 feet tree- and shrub-free entirely. From 5–30 feet, space tree crowns at least 10 feet apart and 10 feet from the home, with no branches over the roof or within 10 feet of the chimney. Increase spacing to 20–30+ feet on slopes, and remove all dead or beetle-killed trees at any distance.

How much defensible space do I need?

A minimum of 100 feet around the home is the Colorado State Forest Service recommendation, more on steep slopes or in heavy fuels, organized into Zone 0 (0–5 ft), Zone 1 (5–30 ft), Zone 2 (30–100 ft) and Zone 3 (100 ft+).

Where are defensible space Zones 1, 2 and 3 located?

Zone 1 is the 5–30 ft band closest to the home, Zone 2 is 30–100 ft, and Zone 3 is everything beyond 100 ft (relevant on acreage). Measure outward from the structure and extend farther downslope, since fire moves faster uphill.

How do I make a moisture map for fire mitigation?

Sketch your property with zones marked, shade irrigated/green areas (fuel breaks) in green and dry, cured, high-fuel areas in red, then track seasonal dryness with live fuel-moisture and drought data so you know where and when to water and thin.

What's the single most effective thing I can do?

Harden the home and the first five feet around it against embers, that's where most homes ignite. Pair it with defensible space to 100 feet and ongoing maintenance.

Is fire mitigation tax deductible in Colorado?

Colorado offers a 25% wildfire-mitigation income tax credit (up to $625/yr, income limits apply), and CSFS grants and Wildfire Partners rebates may offset more. Keep itemized invoices and before/after photos. See our insurance & grants guide.