Condo and strata flooring rules in Canada are the most misunderstood part of a renovation, and every week someone comes to us with a floor they have already bought and a bylaw they have not yet read. The short version, before anything else: no Canadian building code sets a minimum impact-sound rating for your floor. Every IIC number your building enforces comes from its own bylaw — which is exactly why the requirement varies so wildly between one tower and the next. This guide explains what IIC and STC actually measure, why the number on the box is optimistic, what boards typically ask for, and how to assemble a floor that passes. It includes the tested ratings for every acoustic underlay we stock, so you can match a product to your bylaw rather than guess.
Duracoustic 8 mm — the highest-rated acoustic underlay we stock at IIC 92, for buildings with demanding bylaws.
What the Building Code Actually Requires
This is the part that surprises almost everyone, including a fair number of people selling flooring.
The National Building Code of Canada regulates sound transmission between dwelling units. Since the 2015 edition it has done so using ASTC 47 — Apparent Sound Transmission Class — as the minimum for assemblies separating dwelling units. The word apparent matters: ASTC accounts for indirect flanking paths through the surrounding structure, not just sound passing directly through the assembly, which is a meaningful improvement over the older STC-only approach.
But ASTC is an airborne sound metric. It governs voices, music and television. Impact sound — footsteps, dropped objects, chairs dragged across a floor — has no corresponding national requirement. The code does not set an IIC minimum, and impact insulation remains an area flagged for possible future code development rather than a current obligation.
So when an article tells you that "code requires IIC 50" for your condo floor, it is wrong about Canada. Your IIC obligation is contractual, not regulatory. It comes from your condominium declaration and rules in Ontario, your strata bylaws in British Columbia, or the equivalent instrument in your province — and it is enforceable by your board regardless of what any code says.
This distinction is not academic. It explains why the required number differs so much between buildings, why a developer's original spec is not necessarily what your bylaw now demands, and why you cannot resolve the question by reading a code document. You have to read your rules.
IIC vs STC — What Each One Measures
| IIC | STC | |
|---|---|---|
| Full name | Impact Insulation Class | Sound Transmission Class |
| Measures | Structure-borne impact noise | Airborne noise |
| Real-world source | Footsteps, dropped keys, dragged chairs, pets | Voices, television, music, conversation |
| Lab test method | ASTM E492 (standard tapping machine) | ASTM E90 |
| Field test method | ASTM E1007 → reported as FIIC | ASTM E336 → reported as ASTC / NIC |
| Classification standard | ASTM E989 | ASTM E413 |
| Regulated by NBC? | No | Yes — ASTC 47 minimum |
| What your board cares about | This one, almost always | Rarely, for flooring |
Both are single-number ratings derived from measurements across a frequency band, and in both cases higher is better. Flooring disputes between neighbours are nearly always about impact noise, which is why bylaws specify IIC and why underlay manufacturers lead with it.
One limitation worth knowing: the standard tapping machine used in IIC testing is a good proxy for hard-heeled footsteps and small dropped objects. It is a poorer proxy for low-frequency thuds — a child jumping, a dropped dumbbell. Two assemblies with identical IIC ratings can perform noticeably differently against that kind of noise, which is one reason a floor can meet its number and still generate complaints.
The Rating Belongs to the Assembly, Not the Floor
This is the most commonly misunderstood point in the category, and it costs people money.
An IIC number describes a tested system: a specific slab thickness, a specific underlay, a specific floor covering, and often a specific ceiling treatment below. Change any element and the number changes. An underlay does not "have" an IIC of 72 in isolation — it achieved IIC 72 in a particular tested assembly.
The slab matters more than almost anything you control. A rating obtained on a 200 mm concrete slab will not carry over to a 150 mm slab, and a suspended ceiling with insulation below adds points that your building may or may not have. When you submit a test report to your board, the useful question is how closely the tested assembly resembles your actual building.
What this means practically: ask your property manager for the slab thickness and whether there is a finished ceiling below. Two pieces of information, and they change which underlay you should buy.
Lab IIC vs Field FIIC — Why Yours Will Be Lower
Published IIC figures come from ASTM E492, a laboratory test conducted in a facility built specifically to eliminate every sound path except the one being measured. Your building is not that facility.
The field equivalent is FIIC — Field Impact Insulation Class — measured under ASTM E1007 in the actual building, with the actual structure and, in an occupied unit, the actual furniture. FIIC results are routinely several points below the laboratory IIC for the same assembly.
Good Neighbour cork underlayment, 6 mm — IIC 74 and STC 75. Cork is dense, dimensionally stable and does not compress over time the way cheap foam does.
The practical consequence: if your bylaw specifies a number and your chosen assembly tests at exactly that number in a lab, you have no margin. Where the bylaw is a hard threshold and the downstairs neighbour is already unhappy, build in headroom. Choosing an assembly rated a few points above the requirement costs very little at the underlay stage and is dramatically cheaper than relaying a floor.
Note also that some bylaws are written in terms of FIIC rather than IIC, which is a materially stricter requirement. Read the wording carefully — the difference between "IIC 55" and "FIIC 55" can be several points of real performance.
Floor tek Super Silencer — IIC 84 and STC 86 in only 4.5 mm. The best rating-to-thickness ratio we stock.
Flanking — The Path Nobody Tests For
Sound does not only travel straight down through the floor. It also travels sideways into the structure and re-radiates elsewhere — through the slab into the perimeter walls, through rigid connections at the perimeter, through gaps around pipes and around the floor's edge.
This is called flanking transmission, and it is the reason ASTC replaced plain STC in the National Building Code: the code writers recognised that direct transmission alone did not describe what occupants actually hear.
For your installation, flanking is why the perimeter detail matters as much as the underlay. A floating floor that touches the wall at any point creates a rigid bridge for impact energy. Keeping the expansion gap genuinely clear, using a resilient perimeter strip where the assembly calls for it, and avoiding hard contact at door thresholds all contribute more than most people expect. An expensive underlay pinned against the wall by a baseboard nailed through it will underperform a cheaper one installed correctly.
What Canadian Boards Typically Ask For
Since there is no national standard, what follows is what we encounter in the field rather than a rule. Treat it as orientation, and get your own bylaw in writing.
| Market | What we commonly see | Notes |
|---|---|---|
| Metro Vancouver strata | Frequently among the strictest in Canada; higher-end requirements are common in newer towers | Older buildings are often more lenient. Some strata require a test report specific to your unit's assembly |
| Toronto / GTA condos | Commonly cluster around IIC 55, with stricter figures in some newer waterfront towers | Declaration and rules are separate documents — check both |
| Older buildings generally | Sometimes no numeric requirement at all, only "adequate underlay" or a carpet-coverage rule | Vague wording cuts both ways: easier to satisfy, harder to defend in a complaint |
| Buildings with a complaint history | Higher thresholds, sometimes a required post-installation field test | A field test written into the bylaw is the strictest case you will meet |
Two patterns are worth planning around. First, some bylaws limit hard-surface flooring by area — for example requiring that a percentage of the floor be carpeted, or restricting hard surfaces in bedrooms. Second, a number of buildings require an indemnity agreement, under which you accept liability for noise complaints arising from your installation. Neither is unusual, and neither is a reason not to proceed — but both are much easier to handle before you have material on site.
How to Find Your Building's Actual Condo Flooring Rules
Ask your property manager, in writing, for these five things:
- The flooring provisions of the declaration, bylaws and rules — all three documents, since requirements are often split across them
- The required rating, and whether it is expressed as IIC or FIIC
- The slab thickness and whether there is a finished ceiling in the unit below
- The approval process and the form, if one exists
- Whether an indemnity agreement or post-installation testing is required
Keep the reply. If a complaint arises later, written confirmation of what you were told is the difference between a short conversation and a long one. And if the answer is vague — "just use a good underlay" — ask for that in writing too, then choose an assembly with genuine margin anyway.
The Approval Process, Step By Step
- Request the rules before you shop. Choosing a floor first is how people end up returning material.
- Get the slab and ceiling details, so you can match a tested assembly rather than hope.
- Select the floor and underlay together. They are rated as a system; picking them separately is how assemblies miss.
- Obtain the test report for the assembly from the manufacturer. We supply these for anything we sell.
- Submit the package — product spec, underlay spec, test report, proposed installation dates, installer insurance if required.
- Get written approval before material is delivered.
- Install to the tested detail, including the perimeter. Photograph the underlay before the floor covers it.
- Keep the file. Approval, spec sheets, test report, photographs. This is your defence if a complaint arrives in two years.
Every Acoustic Underlay We Stock, Rated
These are the eleven acoustic underlays we carry, with the manufacturer-published ratings and current pricing. As explained above, these figures come from tested assemblies rather than the underlay alone — use them to shortlist, then match the test report to your building.
| Underlay | Thickness | IIC | STC | Price / sq ft |
|---|---|---|---|---|
| Duracoustic™ | 8 mm | 92 | — | $2.29 |
| Floor tek Super Silencer | 4.5 mm | 84 | 86 | $0.69 |
| Memory Foam Underlayment | 3 mm | 77 | 76 | $0.49 |
| Good Neighbour Cork | 6 mm | 74 | 75 | $1.69 |
| Premium Silent IXPE | 3 mm | 74 | 73 | $0.39 |
| LVT & WPC Underlayment | 1.5 mm | 73 | 72 | $0.39 |
| Richmond Silent Performer | 2 mm | 72 | — | $0.69 |
| Daynamix (US made) | 2 mm | 72 | 74 | $0.49 |
| Dura-Son Rubber | 3.5 mm | 69 | — | $1.49 |
| Richmond Quiet Block | 1.5 mm | 69 | 63 | $0.59 |
| Cork Plus 600 | 6 mm | 63 | 61 | $1.59 |
Browse the full range in our acoustic underlayment collection, or see the QuietWalk range specifically. If you need a test report for any of these, ask and we will send it.
Memory foam underlayment — IIC 77 and STC 76 at 3 mm, $0.49 per sq ft.
Choosing an Underlay for Your Bylaw
Higher is not automatically better. Thickness is a real constraint in a condo, and the highest-rated product is not always the right one.
| Situation | Sensible starting point | Why |
|---|---|---|
| Strict bylaw, build height available | Duracoustic 8 mm (IIC 92) | Largest margin in the range; needs 8 mm of height and door clearance |
| Strict bylaw, tight build height | Floor tek Super Silencer 4.5 mm (IIC 84) | The best rating-to-thickness ratio we stock, and inexpensive at $0.69 |
| Mid-range requirement, long service life | Good Neighbour Cork 6 mm (IIC 74 / STC 75) | Cork resists long-term compression better than foam under furniture loads |
| Vinyl or WPC over a slab | LVT & WPC 1.5 mm (IIC 73) or Premium IXPE 3 mm (IIC 74) | Thin, rated for rigid-core floors, keeps the click joint supported |
| Modest requirement, budget-led | Richmond Quiet Block 1.5 mm (IIC 69) | Adequate where the bylaw is lenient; little margin, so confirm the number first |
A caution on soft, thick underlays under rigid floors. A very compressible underlay can allow a floating click floor to flex at the joints, which over time causes gapping and joint failure. Most rigid-core manufacturers specify a maximum underlay thickness and a minimum compressive strength, and installing outside it voids the warranty. Always check the flooring manufacturer's limit before pairing it with a thick acoustic mat — this is the single most common conflict between "meets the bylaw" and "keeps the warranty".
Does an Attached Pad Count?
Most rigid-core vinyl now ships with a factory-bonded IXPE or cork pad, typically 1 to 1.5 mm. It is genuinely useful — it improves underfoot feel and smooths minor subfloor irregularity — but it is designed for comfort, not compliance.
In our experience an attached pad alone rarely satisfies a numeric bylaw. Most boards want a separate rated underlay and a test report for the full assembly. Before you plan to add one, check two things: whether your flooring warranty permits an additional underlay beneath the attached pad (some explicitly do not), and whether the assembly you are proposing has actually been tested in that configuration.
Floor tek Butchart SPC tile — Snowfrost. A 7.5 mm rigid-core tile with an assembly rating of IIC 73.
How Each Floor Type Behaves in a Condo
| Floor | Condo behaviour | What to watch |
|---|---|---|
| SPC / rigid core | Very common. Thin build height, floats over slab, waterproof | Dense core transmits impact readily — the underlay does the work |
| WPC | Quieter and warmer underfoot than SPC | Thicker build; softer core dents more easily under furniture |
| Engineered hardwood | The premium condo choice; floats or glues over slab | Glue-down changes the acoustic assembly entirely — get the right test report |
| Laminate | Workable but the hardest to quieten | HDF core transmits impact efficiently; expect to need a thicker underlay |
| Cork | Naturally the quietest hard surface | Not waterproof; dents under heavy furniture |
| Carpet | Always passes; some bylaws mandate it in bedrooms | Rarely the aesthetic people want, but it ends the argument |
Twelve Oaks Wishbone luxury vinyl — one of 38 floors in our apartment and condo range.
Build Height, Doors and Transitions
Adding a rated underlay adds height, and in a condo that height has consequences. An 8 mm acoustic mat plus a 6 mm floor is 14 mm — enough to bind an interior door, foul a closet track, or create a trip lip at the entry.
Measure before you buy. Specifically: the gap under every interior door, the clearance at the entry door (which usually cannot be trimmed without board involvement, since it is often a fire door), the height at any tiled threshold, and the clearance under built-in cabinetry. If build height is tight, that is the argument for a high-performance thin underlay such as the 4.5 mm Super Silencer at IIC 84 rather than the 8 mm Duracoustic.
Five Expensive Mistakes
- Buying the floor before reading the bylaw. The most common and most avoidable. Restocking a special-order floor is rarely free.
- Assuming the attached pad is enough. It usually is not, and finding out after installation is the worst time.
- Matching the number with zero margin. Lab IIC is a ceiling, not a promise. Field results run lower.
- Ignoring the perimeter. A floor in hard contact with the wall flanks impact energy straight into the structure and undoes the underlay.
- Skipping written approval. Verbal approval from a manager who later leaves is worth nothing in a dispute with a board.
Full-Service vs. Supply-Only — What We Offer
At YaleTown Floor we work two ways — pick the one that fits your project:
Supply Canada-wide. Order flooring and rated acoustic underlay together and we ship anywhere in Canada, with the test report for your board. See delivery across Canada for lead times.
Full-service renovation in the Lower Mainland. In Metro Vancouver and the Fraser Valley we handle the whole job including the strata paperwork: assembly selection, test documentation, submission support, installation to the tested detail, and photographs for your file. Get a fixed-price quote at yaletownfloor.com/pages/consultation-installation.
Why Trust YaleTown Floor on Condo Flooring?
We install in Metro Vancouver strata buildings every week, which means we deal with the paperwork side of this as often as the flooring side — reading bylaws, matching test reports to slab thicknesses, and occasionally telling a customer that the floor they have chosen will not pass and why. That is also why this guide opens by correcting the building-code claim rather than repeating it: getting that wrong sends people looking for a code obligation that does not exist instead of reading the document that actually governs them. We stock eleven rated acoustic underlays and will supply the test report for any of them.
Frequently Asked Questions
What IIC rating does my condo require?
Only your bylaw can tell you. There is no national or provincial minimum, so the figure comes from your declaration, strata bylaw or rules. We see anything from IIC 50 to IIC 70+, with many Ontario boards clustering near 55. Get it in writing from your property manager.
Does the National Building Code of Canada require an IIC rating?
No. The NBC regulates airborne sound between dwelling units via an ASTC 47 minimum. Impact sound has no corresponding national requirement, so any IIC figure your building enforces is a bylaw obligation, not a code one.
What is the difference between IIC and STC?
IIC measures structure-borne impact noise — footsteps, dropped objects, dragged chairs. STC measures airborne noise — voices, music, television. Flooring disputes are nearly always about impact noise, which is why boards specify IIC.
Is the IIC rating a property of the floor or the whole assembly?
The whole assembly — slab, underlay, floor covering and often the ceiling below. A plank or underlay has no meaningful IIC on its own, which is why a rating from a 200 mm slab does not transfer to a 150 mm one.
Why is my measured sound worse than the rating on the box?
Published figures come from ASTM E492 laboratory testing. The field equivalent, FIIC under ASTM E1007, runs several points lower for the same assembly because real buildings have flanking paths laboratories do not. Treat lab IIC as a ceiling.
Do I need board approval before replacing my condo floor?
In most Canadian buildings, yes, for any hard surface. Expect to submit the flooring spec, the underlay spec and a test report, and sometimes an indemnity agreement. Installing without approval risks being ordered to remove the floor.
Which acoustic underlayment gives the highest IIC?
Of what we stock, Duracoustic 8 mm at IIC 92, then Floor tek Super Silencer at IIC 84 in only 4.5 mm, then memory foam at IIC 77. Highest is not always best — thickness affects doors, transitions and click-joint support.
Can I install hardwood or laminate in a condo?
Usually, if the assembly meets the bylaw. Engineered hardwood floats over a slab with an acoustic underlay and is common in Canadian condos. Laminate is the hardest to quieten because its HDF core transmits impact efficiently, so budget for a thicker underlay.
Does an attached pad on the plank satisfy a condo bylaw?
Rarely on its own. Attached pads are 1–1.5 mm and designed for feel, not compliance. Most boards want a separate rated underlay plus a test report — and check whether your flooring warranty even permits an underlay beneath the attached pad.
What happens if I ignore the flooring bylaw?
The board can require removal and reinstatement at your cost, usually triggered by a complaint from below. Since approval normally costs nothing but a form and a spec sheet, it is an avoidable risk.
Get a Real Quote in 24 Hours
Send us your bylaw and we will spec the assembly. Tell us the required rating, the slab thickness if you know it, the rooms and approximate square footage, and how much build height you have under your doors. We will come back with a floor, a rated underlay, the test report your board will ask for, and a real installed number — not a range.
Shop acoustic underlay →Shop condo flooring →Request a quote →
About the author
Max manages YaleTown Floor, a Canadian flooring retailer and full-service renovation team headquartered in Burnaby, BC. The team installs in Metro Vancouver strata buildings weekly and handles acoustic assembly selection and board submissions as part of the job. Questions on this guide? Reach the team via our consultation page.
Shop the Collections
- Acoustic Underlayment — all 11 rated underlays
- Apartment & Condo Vinyl Flooring
- QuietWalk Underlayment
- All Flooring Underlayment
- SPC Vinyl Flooring
- WPC Vinyl Flooring
- Engineered Hardwood
- Cork Flooring
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- What Is SPC Flooring? The Complete Canadian Guide (2026)
- SPC vs. WPC Vinyl Flooring in Canada (2026 Buyer's Guide)
- Underlayment Flooring — Options, Need and Benefits
- The Essential Guide to Vinyl Flooring Underlayment
- Cork Flooring in Canada: Is It Right for Your Home?
- Laminate vs. Vinyl Flooring in Canada (2026 Buyer's Guide)
