You're three weeks from closing on your Colorado home. The title company asks if you want an ILC or a survey. You have no idea what the difference is, so you pick the cheaper option.
Six months later, you're building a fence and discover your neighbor's shed sits two feet onto your property. Now you're looking at a boundary dispute that could cost $10,000-$15,000 in legal fees and surveying work.
The ILC vs. survey decision matters more than most buyers realize. Colorado is one of the only states that offers Improvement Location Certificates, and understanding when each document is appropriate can save you thousands of dollars and years of headaches.
What Is an ILC (Improvement Location Certificate)?
An ILC is a Colorado-specific document prepared by a licensed surveyor. Think of it as a visual inspection of your property that shows where improvements (house, garage, shed, deck) sit in relation to the approximate boundary lines.
An ILC shows:
- Property lines with dimensions and bearings
- Major permanent structures with measurements
- Apparent easements
- The posted address
- Any obvious encroachments
- Found survey pins (if visible)
What an ILC does NOT do:
- Establish exact legal boundaries
- Set or locate property corners
- Provide legal standing for boundary disputes
- Allow you to build a fence (Colorado law prohibits this)
An Improvement Location Certificate is essentially a snapshot that helps identify potential problems. It's not a legal determination of where your property actually ends.
What Is a Full Property Survey?
A property survey (also called an Improvement Survey Plat or Land Survey Plat) is the definitive document for establishing your property boundaries. A licensed surveyor researches deed records, locates original monuments, and physically marks your property corners with stakes or pins.
A survey provides:
- Legally established boundary lines
- Physical markers at property corners
- Documentation that holds up in court
- The foundation for fence construction
- Resolution of boundary questions
When you have a property survey, there's no ambiguity. Those pins in the ground are your legal property limits.
ILC vs. Survey: The Cost Difference
Here's where the decision gets interesting:
- ILC in Colorado: $200-$400 for most residential properties
- Full survey: $600-$1,200+ depending on lot size and complexity
The ILC costs roughly half to one-third of a full survey. That savings is real, but it comes with limitations you need to understand before you choose.
Here's the good news: If your ILC reveals a potential encroachment and you need a full survey, most surveyors will apply your ILC payment toward the survey cost. You're not starting from zero.
When is an ILC enough for Colorado homebuyers?
An ILC is typically sufficient when:
- You're buying a standard residential property with no known boundary issues
- Existing fences appear to match property lines
- The title commitment shows no survey exceptions or easement concerns
- You have no immediate plans to build fences, additions, or structures near property lines
- The property has been surveyed previously and nothing has changed
Most Colorado residential closings use an ILC rather than a full survey. Title companies and lenders are generally comfortable with an ILC for standard transactions.
When do you need a full property survey in Colorado?
You should insist on a full survey when:
- The ILC reveals a potential encroachment (neighbor's fence, shed, or driveway appears to cross the line)
- You plan to build a fence (Colorado law prohibits using an ILC for fence construction)
- You're adding structures near property boundaries (deck, garage, ADU)
- The property is irregular (unusual shape, multiple parcels, or unclear boundaries)
- There's any hint of a boundary dispute with neighbors
- You're purchasing vacant land where improvements haven't defined apparent boundaries
- The title company requires survey exceptions removed from your title policy
The Fence Rule: Why It Matters
Under Colorado Revised Statutes (C.R.S. 38-51-108), an ILC cannot be used to construct a fence. This isn't a suggestion. It's state law.
Why? Because an ILC doesn't establish legal boundaries. If you build a fence based on an ILC and it turns out to be six inches on your neighbor's property, you've created an encroachment. That fence might need to come down, and you could be liable for damages.
If there's an existing fence and it appears to be on the correct boundary, an ILC can confirm that the fence aligns with apparent property lines. But if you're installing a new fence or replacing one where the boundary is uncertain, you need a survey.
What happens if the ILC shows an encroachment?
If your ILC reveals that a neighbor's improvement (or your seller's improvement) appears to cross the property line, you have several options:
- Order a full survey to determine if the encroachment is real
- Negotiate with the seller to resolve the issue before closing
- Request a price reduction to account for potential disputes
- Require the seller to obtain a boundary agreement with the neighbor
- Walk away if the issue is significant and unresolved
Never close on a property with a known encroachment unless you understand exactly what you're inheriting. Boundary disputes don't go away. They get more expensive.
How much does a boundary dispute actually cost?
If an encroachment turns into a legal dispute, you're looking at:
- Full survey cost: $800-$1,500
- Attorney fees: $3,000-$10,000+ depending on complexity
- Court costs: $500-$2,000
- Potential structure removal: $1,000-$15,000+
- Damaged neighbor relationship: Priceless (in the worst way)
The extra $400-$800 for a survey upfront looks pretty reasonable compared to a $15,000 legal battle.
What Your Agent Should Tell You
A good buyer's agent will review your ILC when it comes back and flag any concerns. They should be asking:
- Do any improvements appear close to boundary lines?
- Are there any noted encroachments or overlaps?
- Does the existing fence match the apparent boundary?
- Are there easements that affect how you can use the property?
If your agent just forwards the ILC without comment, they're not doing their job. This document requires interpretation, and potential issues need to be addressed before you close.
Questions to Ask Before Ordering
When deciding between an ILC and survey, ask yourself:
- Do I plan to build a fence in the next five years?
- Are there any structures (mine or neighbor's) within 10 feet of apparent boundaries?
- Is there an existing fence, and does it look professionally installed?
- Does the property have an unusual shape or multiple parcels?
- Has the seller mentioned any boundary discussions with neighbors?
If you answered "yes" to any of these, lean toward the full survey. The peace of mind is worth the extra cost.
Key Takeaways
- An ILC is not a survey. It shows where improvements sit relative to apparent boundaries but doesn't establish legal property lines.
- ILCs cost $200-$400 in most Colorado markets; full surveys run $600-$1,200+.
- Colorado law prohibits using an ILC to build a fence. You need a full survey to install new fencing.
- If your ILC shows an encroachment, order a full survey before closing to determine if the issue is real.
- Most routine residential closings use an ILC, and that's fine for standard transactions with no red flags.
- A boundary dispute can cost $10,000-$15,000+ in legal fees, surveys, and structure removal.
- Spend the extra $400-$800 upfront if there's any doubt. It's the cheapest insurance against future disputes.
The Blue Pebble Approach
At Blue Pebble, we review every ILC that comes back on our buyers' transactions. If something looks questionable, we flag it immediately and discuss your options. We'd rather have an uncomfortable conversation before closing than watch you inherit a boundary dispute.
Most of the time, an ILC is all you need. But when it's not, we'll tell you, and we'll explain exactly why the extra investment makes sense.
That's what having someone in your corner actually looks like.
Have questions about your ILC or survey options? Schedule an appointment and let's talk through your specific situation. Or take our buyer quiz to see what kind of support makes sense for your purchase.