Demilec Attic Cleaning & Rodent Proofing in Chicago: What to Know First
Demilec attic cleaning and rodent proofing in Chicago typically runs between $1,800 and $4,200 depending on attic size, contamination level, and how much exclusion work the roof and soffits need. Most Demilec jobs in the Chicago area take two to five days from initial inspection to final blower-door verification, with the cleaning itself usually completed in one day. We give a written price before any work starts, and we document everything with photos you keep.
This page is for Chicago homeowners with Demilec spray foam insulation who have rodents in the attic, old droppings and nesting material tangled in the foam, or both. We’re Topside Attic Insulation, an independent Demilec service provider working under The Haven Standard since 2016. If you need someone out this week, call (218) 261-7714. A live person answers, 24/7, and a named technician arrives with a written scope already in hand.
How Demilec Products Fail, and How We Fix Them
Demilec spray foam does not fail the way fiberglass or cellulose does. It fails when rodents bore through it, when water gets trapped behind it, or when it was installed over an unsealed deck in the first place. Here is what we actually see in Chicago attics, and what we do about it:
- Heatlok HFO and Heatlok Soya burrowing. Rodents chew through open-cell and closed-cell Demilec foam to create nesting cavities, especially along the top plates where the foam meets the roof deck. The foam’s thermal performance survives, but the air barrier is gone. We remove the compromised section, extract the nesting material, sanitize the cavity, and re-foam once exclusion is complete.
- Sealection 500 sagging in high-humidity attics. Open-cell Demilec foam can hold moisture if a Chicago attic lacks adequate ventilation. Over time we see delamination from the deck, which creates a gap where rodents travel undetected. We cut out the affected areas, correct the humidity path, and reapply.
- AgraSphere-covered foam hiding old activity. Demilec’s AgraSphere soy-based foam gets a crust on the surface after several years. The crust hides old droppings, stains, and chew paths. Cleaning Demilec foam means working that crust carefully so we can see what is underneath before sanitizing. Power-washing or aggressive scraping destroys the foam’s integrity, so we use HEPA vacuums and low-abrasion methods.
- Chicago rodent pressure on Demilec rim joists. Most Chicago homes have unsealed rim joists at the attic knee walls where Demilec foam meets the framing. Mice and roof rats follow the gap between foam and framing. We find this on maybe a third of the Demilec attics we inspect. The fix is sealing the transition with a compatible foam and installing exclusion material at every penetration.
- Demilec foam installed over an unsealed deck. This is the one we see most often after the fact. Insulation was sprayed before the air leaks were sealed, so conditioned air kept moving through the deck, pulled in dust and rodent odor, and the foam never performed to spec. We pull the blower-door numbers, identify the leakage paths, and correct the sequencing before any new material goes in. Seal the holes first. Then add the R-value. The numbers will tell you whether it worked.
Our Demilec Attic Cleaning & Rodent Proofing Process
Every Demilec job in Chicago follows the same sequence. No exceptions under Haven Standard, because the sequencing is what decides whether the problem comes back.
- 1
Blower-door test and attic inspection. We pressurize the house and record the ACH50 reading. Then we walk the attic with a headlamp and document every chew path, dropping field, and transition gap in the Demilec foam.
- 2
Written scope and price. You get a flat price, a written scope, and a written warranty before anyone lifts a tool. We tell you exactly which foam sections come out, what gets sanitized, and what exclusion materials go in.
- 3
Attic cleanout and decontamination. HEPA vacuuming of droppings and nesting material, removal of compromised Demilec foam sections, and application of a hospital-grade disinfectant appropriate for foam surfaces. We photograph everything as we go.
- 4
Rodent proofing and exclusion. We seal every penetration at the roofline, soffits, gable vents, and knee walls. For Demilec attics we use galvanized steel mesh and compatible sealants; we do not rely on foam alone because Chicago rats chew through it in weeks.
- 5
Foam repair and re-insulation where needed. Removed Demilec sections get replaced with a compatible foam. We source materials from Demilec, Owens Corning, Johns Manville, Knauf, Rockwool, CertainTeed, Icynene, and GreenFiber, so you are never locked into a single product line.
- 6
Post-work blower-door test and documentation. We re-test, record the new ACH50, and hand you a printed report with pre- and post-readings, installed R-values by zone, and a photo log of every air-sealing location. The 365-Day Done Right Promise applies to all completed work.
What Demilec Attic Cleaning & Rodent Proofing Costs in Chicago
Most Demilec attic cleaning and rodent proofing jobs in Chicago fall between $1,800 and $4,200. A straightforward cleanout with sanitizing and light exclusion on a 1,200-square-foot attic usually lands around $2,200. A heavily contaminated attic with foam removal and re-foaming along the top plates will push toward $4,000 or more, especially if the ridge vent or soffit areas need re-flashing.
What moves the price: the square footage of Demilec foam that needs removal, how much exclusion material the roof geometry requires, and whether we need to pull permits for structural access. We give one flat written price before any work starts. Call (218) 261-7714 and we will put the number in front of you, in writing, with no pressure.
Why Chicago Homeowners Call Topside Attic Insulation for Demilec Work
Wes Okafor, our owner and lead building envelope technician, grew up on the Northwest Side about six blocks from the Portage Park field house and has been doing insulation work in Chicago for over twenty years. He learned at Truman College’s building technology program that air movement and thermal performance are two sides of the same problem. That is why every Demilec job here starts with a blower-door test, not a sales pitch.
We have sealed and insulated over 9,000 Chicago-area homes since 2016, every one with a written price before work started and a documented record when the crew left. Our techs are background-checked and uniformed. We answer the phone 24/7 with a live person. And when your Demilec attic needs repair, we will tell you honestly whether the existing foam is worth saving or whether replacement makes more sense. We also service Reflectix attics, so multi-brand homes are not a problem. Under Haven Standard: you get a named technician, a text when they are on the way, and a written warranty in hand before anyone lifts a tool.
FAQs
In our experience, Demilec’s warranty language covers manufacturing defects in the foam product itself, not damage from rodents, water intrusion, or installation errors. As an independent Demilec service provider, we cannot speak for the manufacturer’s claims process, but we have never seen a rodent-related attic claim paid out. The practical answer is that remediation and exclusion are on the homeowner. We give you a written scope so you have documentation if you choose to pursue a claim.
We schedule Demilec attic cleaning and rodent proofing work in Chicago within the same week in most cases. Emergency calls, like a raccoon that tore through a section of Demilec foam and is still in the attic, get same-day or next-day attention. Call (218) 261-7714 and a live person will give you a straight answer on scheduling.
We can repair most Demilec foam in place. The sections that need to come out are those compromised by rodent burrowing, moisture-saturated open-cell foam, or foam that has delaminated from the deck. Healthy Demilec foam stays. We will show you photos of what we removed and what we left, so you are not paying for unnecessary demo.
We source materials from Demilec, Owens Corning, Johns Manville, Knauf, Rockwool, CertainTeed, Icynene, and GreenFiber, with no proprietary product lock-in. For Demilec repairs, we aim to match the existing foam type and density with a compatible product. If matching the exact Demilec line matters to you, we will tell you upfront what that costs and what lead time it adds.
Cleaning and proofing a Demilec attic usually runs $1,800 to $4,200, while full foam removal and re-insulation in Chicago starts around $6,000 and goes up from there. If the foam is intact and only the surface and nesting material are the issue, cleaning is the better financial call. If the rodents have tunneled through more than a third of the foam’s coverage area, replacement often costs less than piecemeal repairs. We will run the numbers both ways and give you the written comparison.
Written by Wes Okafor, Owner & Lead Building Envelope Technician, Topside Attic Insulation at Topside Attic Insulation, serving Chicago and nearby areas.