A new floor in a condo or an association home has to clear two sets of rules: your municipality's and your association's. The first is usually simple. The second is where jobs stall. Here is what each one asks for, what IIC and STC actually mean, and how to put together a packet your board will approve the first time.
The short answer
Swapping one floor covering for another usually needs no building permit in the towns we work in. Naperville, Aurora and Warrenville all say so on their own permit pages. What changes that is structural, basement or remodel work bundled with the floor. In a condominium, though, the rule that actually governs your floor is the association's: most buildings require board or management approval, and many set a minimum sound rating for hard floors and the underlayment under them.
Get the association's flooring rules in writing before you choose a product, and get the underlayment approved before the installation date is booked. That order avoids almost every condo flooring problem we see.
A homeowner in a detached house can usually pick a floor, book an installer and be done. In a condominium, a townhome community or a single-family subdivision with an architectural review committee, there is a second decision-maker in the room. It is not a formality. In a stacked building, the floor you put down is the ceiling your downstairs neighbour lives under, and the association has both the authority and a good reason to care what goes on it.
This guide walks through both layers the way they come up on a real job: when your village or city wants a permit, who issues it, why associations regulate hard floors, what the sound ratings in their rules mean in plain English, which underlayments change the result, and what to send your board. If you are still choosing a material, our vinyl plank vs. hardwood comparison covers how each one looks, feels and sounds, and our installation cost guide covers what new flooring and subfloor prep run in the western suburbs.
In this guide
Start with the good news. Replacing a floor covering, on its own, is treated as cosmetic work by the municipalities we checked, and cosmetic work does not need a building permit. Three of the towns we serve put it in writing on their own permit pages:
That last condition is the useful one, because it describes exactly when a flooring job stops being cosmetic. In practice, the floor itself rarely triggers a permit. The work around it does:
Every town writes its own list. The three pages above are typical but not universal, and each one says some version of “if your project is not listed, ask.” Before structural or basement work, call your village or city building department. We flag permit questions at the estimate so they are settled before anything is ordered.
Naperville sits in two counties: the north side is in DuPage County and the south side is in Will County. That surprises people, but it does not change who handles a building permit. Inside city limits, the City of Naperville issues building permits, whichever county your tax bill comes from. The same is true in Downers Grove, Lisle, Wheaton and every other incorporated village: the village or city is the permit office.
The county only becomes your building department if your home is in unincorporated territory, outside any village's limits. Some subdivisions with a Naperville, Wheaton or Downers Grove mailing address are unincorporated, so the address on your envelope is not a reliable guide. Your property tax bill or the county's parcel lookup will tell you which jurisdiction you are in.
For a condo owner this distinction rarely matters in practice, because a floor-covering swap needs no permit either way. It matters when the floor is part of bigger work, and then it is worth knowing before you phone the wrong office.
In a condominium the floor is not just yours. Underneath your finished floor is a concrete slab or a wood-framed floor that is part of the building, and underneath that is someone else's ceiling. Carpet and pad soak up footsteps. Hard flooring laid tight to a slab does not, and the result travels.
The complaint associations hear is almost never about voices or a television. It is impact noise: heels, a dropped pan, a dog's nails, a chair dragged across the room, all transmitted through the structure into the unit below. Replace a carpeted condo with hardwood or vinyl plank and nothing else, and the downstairs neighbour often hears the difference within a week.
That is why so many condominium buildings have flooring rules, and why those rules focus on what goes under the floor. In Illinois, the Condominium Property Act gives a condo board the power to adopt and amend rules and regulations covering the operation and use of the property, after a meeting of unit owners called for that purpose (765 ILCS 605/18.4(h)). Flooring rules usually live in those rules and regulations or in the declaration itself. They vary a great deal from one building to the next, so the only rule that counts for your unit is your own association's.
Two ratings show up in condo flooring rules and in the test reports that come with underlayment products. They measure different kinds of sound.
For both, higher is better. A higher IIC means less footstep noise reaches the unit below.
The building code gives a useful reference point. Naperville enforces the 2024 International Building Code, and Section 1206 of the 2024 IBC sets sound requirements for floor-ceiling assemblies between dwelling units in buildings like condominiums. Section 1206.2 requires an STC of at least 50 when lab-tested to ASTM E90, or a field-tested Normalized Noise Isolation Class (NNIC) of at least 45. Section 1206.3 requires an IIC of at least 50 when lab-tested to ASTM E492, or a field-tested Normalized Impact Sound Rating (NISR) of at least 45 to ASTM E1007. The IBC covers multi-unit buildings. Detached houses and most townhomes fall under the residential code instead, so no IIC number applies to them.
Three things about those numbers trip people up:
Underlayment is the layer between your finished floor and the slab or subfloor, and in a condo it does most of the acoustic work. There are a few broad families, and each pairs with particular installation methods:
How the floor is fastened matters as much as what is under it. Over a concrete slab, hardwood is either glued down, sometimes onto an acoustic mat that is itself glued to the slab, or floated over a pad. Nail-down installation needs a wood subfloor, which most high-rise concrete buildings do not have. The underlayment has to be one rated for the method you are using, and the flooring manufacturer has to accept it, or the warranty is at risk.
A rule of thumb that holds up: choose the underlayment and the floor together, from the association's rule backwards. Pick the floor first and you may find the only underlayment your building accepts is not approved by that floor's manufacturer.
Most mid- and high-rise condo buildings have concrete floors, and that narrows the choice. Solid hardwood is normally nailed to a wood subfloor and moves with humidity, so it is a poor match for a bare slab. Engineered hardwood, a real wood wear layer on a cross-layered core, is far more stable and can be glued down or floated over a slab with the right underlayment. That is why it is the usual answer for real wood in a concrete building. Luxury vinyl plank is the other common choice, and it is often what associations see most.
A slab also brings moisture questions, the same ones a basement does. Our basement flooring guide covers slab moisture testing, and the hardwood flooring service page covers solid and engineered wood in more depth. Older low-rise condo buildings and most townhomes have wood-framed floors, which opens up nail-down options, though the association's sound rule still applies.
Townhome communities and single-family subdivisions are a different animal. Most have no sound rule for interior floors, because there is no unit directly below. What they often do have is an architectural review process, and the City of Naperville's own permit guide reminds residents to check with their homeowners association for additional requirements.
Architectural review usually focuses on exterior changes, but some associations also want to know about interior work that affects shared walls or common areas, or that brings contractors, dumpsters and trucks into the neighbourhood. Typical requests are a short description of the work, the contractor's name and certificate of insurance, the dates, and where the trucks and debris will go. Townhomes with shared walls sometimes have rules about work hours and noise too. If your declaration is silent on flooring, a short note to the management company before the job is a courtesy that heads off a neighbour complaint.
Boards and property managers approve complete requests quickly and sit on incomplete ones. Ask your manager for the building's flooring rules and any request form, then send everything at once. A typical packet looks like this:
Approval in hand, book the installation date, not before. A floor ordered before the underlayment is approved is a floor that may sit in boxes while the paperwork catches up.
The practical rules in a condo building shape the schedule as much as the floor does. The ones that come up on almost every job:
We get asked what happens if an owner skips the process. The honest answer is that it depends on your declaration and rules, which set out the association's remedies, and those vary from building to building. What is consistent is that the burden lands on the owner: an association that receives a noise complaint about an unapproved hard floor can ask for proof of what was installed, and if the floor or its underlayment does not meet the rule, the fix can mean taking up a brand-new floor. Getting approval first costs a few weeks. Getting it afterwards can cost the floor.
If you are buying a condo with hard floors already in it, it is worth asking whether they were approved. If you are selling, having the approval letter on file is a small thing a buyer's attorney may ask for.
Most of our work is in single-family homes across DuPage, Will and Kane County, but we also install in condominiums. One of the projects in our gallery is a white oak herringbone installation in a downtown Chicago high-rise, with floor-to-ceiling windows on the lake. It is outside our usual service area, and we show it here for one reason: it is a full condo installation in a concrete high-rise, with every constraint in this guide in play, from protecting finished walls and artwork to working inside the building's rules for access and hours.
Herringbone adds its own demands in any building: each board is cut and fitted individually, and the pattern magnifies any unevenness in the surface underneath, so flattening comes first.
Before we price a condo or association job, we want to know:
Then we help you put together the packet. Our flooring installation for condos and townhomes covers hardwood, vinyl and laminate, and we work across Naperville and the western suburbs. If your association has handed you a set of rules you are not sure how to read, send them over with your estimate request.
Usually not, if the job is only replacing one floor covering with another. The City of Naperville's Guide to Building Permits lists carpeting among the cosmetic improvements that do not need a permit, and the City of Aurora and the City of Warrenville both say flooring by itself does not need one. A permit comes into play when the job includes structural repairs, a basement or other remodel, or electrical or plumbing changes. Each town writes its own list, so check with your village or city building department for anything beyond a straight floor swap; we flag it at the estimate.
Whatever your association's declaration and rules say. There is no single number for every building, and some buildings ask for more than the building code minimum. For reference, the 2024 International Building Code requires floor-ceiling assemblies between dwelling units to reach IIC 50 when lab-tested, or a field-tested NISR of 45. Ask your manager for the rule in writing, and ask whether it means a lab report for the floor assembly or a field test after installation.
STC (Sound Transmission Class) measures airborne sound such as voices and television, and depends mostly on the slab, ceiling and walls. IIC (Impact Insulation Class) measures impact sound such as footsteps and dropped objects, and it is the rating your new floor and underlayment affect most. For both, a higher number means better sound isolation. Condo flooring rules usually focus on IIC.
Yes, usually as engineered hardwood glued down or floated over an underlayment rated for that method. Solid hardwood is normally nailed to a wood subfloor and moves with humidity, so it is a poor fit for a bare slab. The slab has to be checked for flatness and moisture first, and the underlayment has to satisfy both your association's sound rule and the flooring manufacturer's warranty.
Typically the building's request form, the flooring product's spec sheet, the underlayment's spec sheet and acoustic test report, the installer's certificate of insurance with the wording the manager asks for, the rooms and square footage, the schedule and work hours, and a plan for protecting common areas and removing debris. Send it all at once, and book the installation only after approval.
No pressure, no obligation. We come to you, assess your floors, and give you an honest quote. Most responses within a few hours.