Common Errors in Xactimate Roof Estimates (and How to Avoid Them)

Why I’m Writing This

I see the same Xactimate mistakes over and over.
This post is not about your insurance policy.
Bert Roofing is a contractor, not a public adjuster.
Coverage questions are outside our scope.

My goal is simple: help you how to spot write a proper roof estimaWe won’t hit every situation.
We will hit the common errors and omissions that cost money.
Most low estimates share one trait: missing line items.
Things get skipped.
Let’s fix that.

If-Incurred Items: Easy to Miss, Expensive to Forget

An if-incurred item is paid only if you actually do the work.
You’ll often see a $0 placeholder in the estimate.
Payment follows proof of completion on the final invoice.

Typical examples: permits, double underlayment on low slopes, extra tear-off layers, small deck repairs, crane time, and dumpster overages.
These get missed on final billing more than you think.

How to capture them

• Flag all $0 lines before production.
• Train crews to note triggers like low slope and hidden layers.
• Collect clear photos.
• Add the cost when you incur it.
• Audit the invoice against every $0 line.

Debris Removal: Dumpster vs. Haul-Off

In DFW, most roofers haul their own debris.
Dumpsters are not the local norm.
If you price “tear off only” and add a dumpster, the math can look cheaper.
Often, it isn’t.

Real example (about 45 squares)

• Tear off with haul-off: $3,060.
• Tear off only: $2,077.
• One 20-yard dumpster: $456.
• Combined: $2,533.
  It looks $500+ lower than haul-off.

But a 20-yard dumpster often includes about 4 tons.
Xactimate Components showed ~6.43 tons for a job this size. 
You’ll need two pulls.
Now you’re at $2,989 before any overages.
The “savings” just evaporated.

What to write

• If you self-haul, use tear off + haul-off as one line.
• If you use dumpsters, match count to weight.
• Add overage or second pull when needed.
• Keep the language neutral and accurate.

Different Trades Don’t Share Dumpsters When There’s No O&P

Gutters often get replaced with the roof.
That adds debris.
If overhead and profit (O&P) is not included, there is no GC.
No GC means no shared dumpster between trades.
Each trade should carry its own debris removal line.

Ridge Caps: Enhanced vs. Cut 3-Tab

Most homes use one of two ridge options:

• Cut 3-tab ridge, made from strip shingles.
• Enhanced ridge, like GAF Z-Ridge, TimberTex, or Seal-A-Ridge.

Both can be correct when installed per specs.
They look different and price different.
Enhanced ridge typically costs about $3 per linear foot more than cut 3-tab.
At 300 LF, that’s about $900 you’ll miss if you default to cut 3-tab.

What to write

• Add a distinct enhanced ridge line when present.
• Enter the actual LF of hips and ridges.
• Note the product (Z-Ridge, TimberTex, etc.).
• Attach a label photo for proof.
• Don’t bury ridge in “waste.”

Manufacturer references
See GAF’s product and install guides for Z-Ridge, TimberTex, and Seal-A-Ridge. (GAF, GAF Documents)

Drip Edge: Replace Eaves and Rakes, and Match Code

Many estimates replace only rake metal.
That is a common error.
Replace eaves and rakes to meet code and manufacturer guidance.

Why “rakes only” is wrong

• Underlayment layering: at eaves it goes over the metal; at rakes it goes under.
• Gutters: new fasteners rarely hit old holes.
  Leaving old eave metal creates a perforated mess.
• Size: the IRC requires drip edge at eaves and rakes, with specific overlaps and leg dimensions.
  1.5″ × 1.5″ usually fails the 2″ roof-leg requirement.
  Use 2″ × 2″ or 1″ × 2″ profiles that meet the rule. (ICC Digital Codes )

GAF technical note
GAF strongly recommends drip edge at eaves and rakes and details shingle overhang limits. (GAF Documents)

What to write

• Separate lines: Replace drip edge – eaves and Replace drip edge – rakes.
• Specify profile, size, color, and min 0.019″ thickness.
• Note that gutter replacement requires new eave metal.
• Reference the IRC section in your line note. (ICC Digital Codes)

Deep dive
The Asphalt Roofing Manufacturers Association has a current best-practice sheet on drip edge layering at eaves and rakes. (Asphalt Roofing)

Further reading
See our own write-up: “Drip Edge: The Most Common Roof Mistake.” (DFW Roofing)

Omissions: Chimneys and Crickets\

Chimney work is often missing.
That is a plain omission.
A typical chimney flashing scope is a meaningful ticket.

What to include

• Remove old apron and step flashing.
• Install new apron, step
• Seal and reglet as needed.
• Add leak barrier and underlayment per guide. (GAF Documents)

Crickets for wide chimneys
A chimney over 30 inches wide needs a cricket.
That is an IRC requirement.
Add it or mark it if-incurred pending field verify. (ICC Digital Codes)

Helpful references

• GAF guidance on chimney flashing and cricket details. (GAF Documents)

Lead Collars: Don’t Detach and Reset

Lead is very soft.
Once you bend a lead collar, it rarely returns to form.
Detach-and-reset is poor practice on reroofs.

Best practice

• Remove and replace the plumbing vent flashing.
• Use a new lead collar or a purpose-built pipe boot.
• Follow the install PDF and photo-document the work. (GAF Documents, GAF)

“Included in Waste” — No, It Isn’t

A roof has three shingle types: field, starter, and hip/ridge.
Xactimate prices them separately.
Do not bury starter or ridge in field “waste.”
You will under-scope the job and lose money.

The math

• Starter vs. 3-tab used as starter: about $160 vs. $106 per bundle.
  Delta $54 per ~75 LF.
• Ridge vs. 3-tab used as ridge: about $178 vs. $106 per bundle.
  Delta $72 per ~33 LF.
  A typical home with 3 starter bundles and 9 ridge bundles loses about $810 if you lump.

What to write

• Add three lines: field shingles, starter, and hip/ridge.
• Enter actual LF for starter and ridge.
• Note the GAF product if upgraded ridge is present.
• Keep “waste” for field only.

Manufacturer references

• GAF Pro-Start and WeatherBlocker starter instructions. (GAF Documents, GAF)
• GAF TimberTex and Seal-A-Ridge instructions. (GAF Documents)

Symbility Is Rising: Watch the Language

Xactimate is still the standard.
Symbility (an alternative to Xactimate) is gaining ground.
Used correctly, results are similar.
Used loosely, errors slip in.

Where mistakes hide

• Different line names and defaults.
• Unit confusion (LF, EA, SQ).
• Waste logic that ties to the wrong thing.
• Tear-off lines that don’t include haul-off.
• Steep/height adds that don’t translate.

How to protect yourself

• Build a crosswalk of your top roofing lines.
• Lock the units for each line.
• Add clear line notes on scope and materials.
• Attach photos and labels.
• Audit against your Xactimate baseline before you send.

Conclusion

This guide is not everything.
It covers the common mistakes I see most.
Write scopes that match code and GAF instructions.
Train your team to capture if-incurred items.
Price starter and ridge separately.
Replace drip edge at eaves and rakes.
Don’t “share” dumpsters without O&P.

One more note for Texas homeowners:
State law bars a contractor from acting as a public adjuster on the same property.
We do not give policy advice.
We give software and scope advice so your estimate reflects the actual build. (Texas Statutes, Texas Department of Insurance)

Should gutters be included?