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Mold Remediation Cost Calculator
Remediation is priced by one measurement — the square footage of affected area — at $10–$30 per square foot. Below about 10 square feet the EPA says most people can handle it themselves, and this page tells you that before it shows you a number. This prices remediation work. It is not a health assessment and nothing here says anything about species or exposure — a bigger figure means more square feet, not a worse risk.
Educational calculators — always consult a licensed professional before making financial decisions.
The area of contaminated surface — this is the only thing that sets the price.
A published cross-check on the figure above, not a surcharge on it.
$1,500–$4,000 on Fixr; This Old House and Bob Vila both say $500–$3,000. A genuine disagreement, not a rounding gap.
The one thing that genuinely adds to a per-square-foot price.
Adds nothing. The normal answer when growth is confined to a surface and the air handler has not been running through it.
Select all that apply. Both are separately ordered and separately invoiced.
Estimated remediation cost
$1,500 – $4,500
150 sq ft affected · basement · full containment
This is a price for remediation work, and nothing else. It says nothing about species, exposure, or whether anyone has been made unwell — a bigger figure here means more square feet, not a worse health risk. It also excludes putting back whatever comes out, which every publisher prices as a separate job.
Full containment. EPA recommends full containment above 100 square feet: double layers of polyethylene, a constructed decontamination chamber or airlock, and negative pressure maintained relative to the surrounding space. That level is the EPA's recommendation for your affected area and it adds $0 to the figure above — not because containment is free, but because nobody publishes what it costs. The EPA publishes no dollar figures for mold work at all, and no cost publisher prices containment as a tier. The only containment figure that exists anywhere is Fixr's hourly labour rate of $75–$120 plus equipment “usually under $100”, and no published hour count to apply it to. Inventing a containment surcharge would have made this page look more precise and be less true.
The second opinion is lower. The arithmetic above uses Fixr's published $10–$30 per square foot. This Old House and Bob Vila both publish $10–$25, and Fixr's own page quotes a restoration firm at $10–$25, contradicting its own ceiling. At the lower rate your 150 sq ft would be $1,500–$3,750 for the remediation line. Read the figure above as the conservative end. Note also that This Old House and Bob Vila both source their cost data from Angi, so where they agree with each other that is one dataset rather than two publishers.
Where the money goes
Not in your total: mold inspection and air sampling (before) ($450–$800) and post-remediation air clearance test (after) ($500–$700). The inspection is what produces the square footage this whole estimate rests on, and a remediation contractor measuring it is measuring their own job. The clearance test is the only thing that gets you a document saying the area was clear before the wall went back up, and it is what an insurer is most likely to ask for.
Putting it back is a separate bill. Remediation removes contaminated material; it does not replace the drywall, flooring, framing or cabinetry that came out. This Old House states plainly that those repairs “are often priced separately from the remediation work” and then attaches no figure. The three figures that do exist describe three different scopes and cannot be reconciled into one line: Fixr puts mold damage repair at $75–$3,000 “in addition to the remediation costs” and full restoration on severe problems at $10,000–$20,000, while Bob Vila puts significant damage at $2,000–$20,000. None of them is added above.
Your policy probably has a mold sub-limit. NerdWallet reports that insurers “usually cap payouts at $1,000 to $10,000” on mold specifically, separately from the rest of the policy, with a rider sometimes available to raise it. That is a tenfold spread in a cap, so it is worth reading your own declarations page rather than assuming. Whether a given loss is covered at all turns on what caused the water, not on the cap — this is a cost page, not coverage advice.
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The EPA's 10 square feet is the most useful number on this page
It comes before the cost tables because for a lot of readers it makes them irrelevant. The EPA's guidance, verbatim: “If the moldy area is less than about 10 square feet (less than roughly a 3 ft. by 3 ft. patch), in most cases, you can handle the job yourself.” Above that, it says to consult its remediation guide.
The practical consequence: a patch behind a shower surround is usually under the line, and a contractor pricing it is quoting a minimum call-out rather than a measured job. Two caveats travel with the guidance and both matter — it does not apply if the water came from sewage, and Bob Vila adds that it does not apply if anyone in the household has respiratory sensitivities.
What the EPA does not publish is any dollar figure at all, for anything, on mold. Every number on this page comes from a cost publisher; every threshold and every containment definition comes from the EPA. Keeping those two straight is most of what makes this topic possible to write about honestly.
What remediation costs, by affected area
Area sets the price because area sets the material removed, the containment built and the hours worked. Fixr publishes the rate as $10–$30 per square foot, and multiplying it out reproduces its own published size table across all eight rows with zero discrepancies — the table below is theirs, not a derivation of ours. That exactness is why this calculator runs off the rate rather than off any published average.
| Affected area | At $10–$30/sq ft | At $10–$25/sq ft |
|---|---|---|
| 50 sq ft | $500–$1,500 | $500–$1,250 |
| 100 sq ft | $1,000–$3,000 | $1,000–$2,500 |
| 150 sq ft | $1,500–$4,500 | $1,500–$3,750 |
| 200 sq ft | $2,000–$6,000 | $2,000–$5,000 |
| 300 sq ft | $3,000–$9,000 | $3,000–$7,500 |
| 500 sq ft | $5,000–$15,000 | $5,000–$12,500 |
| 1,000 sq ft | $10,000–$30,000 | $10,000–$25,000 |
| 1,200 sq ft | $12,000–$36,000 | $12,000–$30,000 |
The middle column is Fixr's, verbatim. The right-hand column is the same area at the lower rate This Old House and Bob Vila both publish — $10–$25 per square foot — which is also the rate Fixr's own page quotes from a restoration firm, in contradiction of Fixr's own ceiling. The calculator uses Fixr's band, so read it as the conservative end and the right-hand column as the other publisher's view.
Be careful with the national average on this topic
Four publishers appear to converge on about $2,300, and it is worth showing why that is less reassuring than it looks:
| Publisher | Average | Where its data comes from |
|---|---|---|
| Fixr | $3,500 | Its own cost tables |
| This Old House | $2,300 | States its cost data was sourced from Angi |
| Bob Vila | $2,254 | Cites Angi and HomeAdvisor |
| NerdWallet | $2,368 | Attributes the figure to Angi |
Three of the four trace to the same upstream dataset, so the tight $2,254–$2,368 cluster is one source counted three times, not three publishers agreeing. Angi itself returned HTTP 403 to automated retrieval on 11 September 2026 and could not be checked, and HomeGuide — the other publisher that maintains an independent mold table — was also 403. That leaves Fixr's $3,500 as the only independently-sourced average retrieved, roughly 50% above the cluster. It is also why this calculator prices from a measured per-square-foot rate rather than anchoring on an average at all.
Containment: the EPA defines it, nobody prices it
Containment is what stops a remediation from spreading spores through the rest of the house, and the EPA's guidance turns on affected area rather than on how bad the growth looks. Its thresholds are below, in its own terms.
| Affected area | EPA level | What it involves |
|---|---|---|
| Under 10 sq ft | No containment required | EPA's Table 2 puts an affected area under 10 square feet in its SMALL tier, for which containment is "None required" — and the same guidance says a patch that size can in most cases be handled by the homeowner. |
| 10 – 100 sq ft | Limited containment | EPA recommends limited containment for 10 to 100 square feet: a single layer of 6-mil fire-retardant polyethylene sheeting with a slit entry and covering flap, held under negative pressure. |
| Over 100 sq ft | Full containment | EPA recommends full containment above 100 square feet: double layers of polyethylene, a constructed decontamination chamber or airlock, and negative pressure maintained relative to the surrounding space. |
Both levels must be held under negative pressure, and the EPA gives a field test for whether yours is working: “If the containment is working, the polyethylene sheeting should billow inwards on all surfaces.” Worth knowing if you are standing in your own house watching someone build one.
This calculator derives your containment level from your area and charges nothing for it. That is a deliberate refusal rather than an oversight. The EPA publishes no dollar figures for mold work at all. No cost publisher prices containment as a tier. The only containment money figure retrievable anywhere is Fixr's $75–$120 hourly labour rate plus equipment “usually under $100”, and there is no published hour count to multiply it by. A “full containment adds 20%” coefficient would have made this page look more precise and be less true.
Location is a second view of the same job, not a surcharge
Fixr publishes by-location bands as well as the per-square-foot rate: a bathroom at $500–$1,500, a crawl space at $500–$2,000, a basement at $1,500–$4,000, an attic at $1,500–$9,000, walls at $1,000–$12,000 and a whole home at $10,000–$30,000. Those describe what jobs of typical size for that room cost — they are a summary of the same arithmetic, not an additional charge — so this calculator prices from your area and uses the location band as a cross-check. When the two fail to overlap it says so and leaves your number alone.
Two locations carry genuine publisher disagreement rather than rounding noise. Fixr puts a basement at $1,500–$4,000 where This Old House and Bob Vila both say $500–$3,000, and an attic at $1,500–$9,000 where they say $1,000–$4,000. Where all three do agree is worth recording as the better-sourced half of this data: crawl space $500–$2,000, HVAC $3,000–$10,000, and whole home $10,000–$30,000 are identical across all three publishers.
The two things that genuinely add to the bill
The HVAC system, because a duct run is not a surface — it is a separate mobilisation with different equipment. Fixr, This Old House and Bob Vila all publish $3,000–$10,000 for whole-system remediation, the strongest three-way agreement in this dataset. Watch the scope names, though: Fixr prices a single vent at $100–$500, Bob Vila prices air ducts alone at $600–$2,000, a radiant system is $1,500–$5,000 and a furnace or air handler $3,000–$5,000. Four similar names, four different jobs.
Testing, at both ends. The inspection beforehand is $450–$800 and it produces the affected square footage that this entire estimate rests on — worth buying from someone who is not also quoting the removal. The clearance test afterwards is $500–$700 and is the only thing that gets you a document saying the area was clear before the wall went back. On that second figure, a disclosure: no publisher prices a post-remediation clearance test as its own item. That band is Fixr's mold air testing figure — the same test, ordered after the work rather than before — which is the closest published number that exists. Fixr confirms the practice without pricing it, and This Old House names third-party post-remediation testing as a cost line and attaches no figure at all.
What this calculator assumes, stated plainly
- It prices remediation, not health. Nothing here is medical information. No output says anything about species, exposure or whether anyone has been made unwell, and a larger figure means more square feet rather than a worse risk. This is the one home-cost topic where the search is frequently frightened rather than budgetary, and the honest response is to be narrow about what the number covers.
- The arithmetic is Fixr's, and its remediation page is dated August 2025. Its inspection page is dated January 2025. So the priced figures are 2025 tables read in September 2026; the EPA pages are all 2026. Fixr's page also still carries a stranded line about 2023 cost projections, which is a fair reminder that a stated update date and the vintage of every figure on a page are not the same thing.
- No species pricing, deliberately. Bob Vila publishes bands by mold genus and for “black mold”. Those are not carried here, because species is established by a lab after sampling rather than by a homeowner before quoting, and an input for it would invite self-diagnosis on exactly the topic where this site should least encourage it.
- No regional multiplier. Every publisher quotes national figures and none publishes a regional table.
- Reconstruction is excluded. Putting back drywall, flooring, framing or cabinetry is a separate job that every publisher prices separately, and the three figures that exist cover three different scopes: Fixr's mold damage repair at $75–$3,000 “in addition to the remediation costs”, Fixr's severe-problem restoration at $10,000–$20,000, and Bob Vila's significant damage at $2,000–$20,000. None of them is summed into your total.
- Insurance is mentioned, not modelled. NerdWallet reports mold sub-limits of $1,000–$10,000, separate from the rest of a policy. Whether a loss is covered turns on what caused the water, which is a coverage question rather than a cost one.
- Labour is about 60% of a quote, per Fixr — “Approximately 60% of the project's cost is for labor, and the other 40% is for materials”. Useful for reading a quote; not used in the arithmetic, because the per-square-foot rate already contains both.
Related calculators
Mold is a symptom of water, so the useful next question is where the water came from. If it is groundwater against the foundation, the sump pump & French drain cost calculator prices the fix that stops it recurring — remediating without it is paying twice. If the basement wall is cracked or bowing as well as damp, the foundation repair cost calculator prices that side by scope of work.
If this came up during a purchase, the home inspection cost calculator prices mould sampling as one of its add-on tests, and the home insurance cost calculator is the place to start on what a policy costs — though the mold sub-limit above is the part of it that decides who pays for this.
Methodology & sources
The cost figures on this page are generated from a single, sourced cost-data file (Professional remediation of mold-contaminated material in a US home — containment, removal of affected porous material, HEPA cleaning and treatment of the area — priced from the square footage of affected area, which is the measurement every publisher prices this work by. This is a price for remediation work only: it is not a health assessment, says nothing about species or exposure, and excludes the reconstruction needed after contaminated material is removed, which every publisher prices as a separate job. Figures are US national and reflect Fixr's mold remediation cost tables as published 29 August 2025 and its mold inspection tables as published 31 January 2025. Containment levels and the DIY threshold are the EPA's own definitions and carry no cost, because the EPA publishes none.). Fixr prices remediation at $10-$30 per square foot of affected area and publishes a size table that multiplies out from exactly that rate; This Old House and Bob Vila both publish the lower $10-$25, and Fixr's own page quotes a restoration company at $10-$25, contradicting its own ceiling. The arithmetic here uses Fixr's band and shows the second opinion beside it. On national averages the published record is weaker than it appears: This Old House, Bob Vila and NerdWallet all trace their averages to Angi, which could not be retrieved on 11 September 2026, so their apparent agreement near $2,300 is one dataset counted three times against Fixr's independently-sourced $3,500. Containment level is derived from the EPA's own area thresholds and adds nothing to the total, because the EPA publishes no costs and no cost publisher prices containment as a tier. Last verified September 2026.
- Fixr.com — Mold Remediation Cost (page last updated 29 Aug 2025) — retrieved 2026-09-11
- Fixr.com — Mold Inspection Cost (page last updated 31 Jan 2025) — retrieved 2026-09-11
- US EPA — Mold Cleanup in Your Home (the 10 sq ft DIY threshold; page last updated 4 Jun 2026) — retrieved 2026-09-11
- US EPA — Mold Remediation in Schools and Commercial Buildings Guide, Chapter 3: containment levels (page last updated 29 Apr 2026) — retrieved 2026-09-11
- US EPA — Mold Remediation Guide, Chapter 5, Table 2: remediation guidelines by affected area, credited to IICRC S500 (page last updated 14 Apr 2026) — retrieved 2026-09-11
- This Old House — How Much Does Mold Remediation Cost? (page updated 11 Mar 2026; its cost data is sourced from Angi) — retrieved 2026-09-11
- NerdWallet — Does Homeowners Insurance Cover Mold? (page updated 11 Jun 2026) — retrieved 2026-09-11
Frequently asked questions
How much does mold remediation cost?+
Fixr publishes mold remediation at $10–$30 per square foot of affected area, which is how the work is actually priced — so a 50 sq ft patch is $500–$1,500 and a 300 sq ft job is $3,000–$9,000. By location the published bands run $500–$1,500 for a bathroom, $500–$2,000 for a crawl space, $1,500–$4,000 for a basement, $1,500–$9,000 for an attic and $10,000–$30,000 for a whole home, giving an overall $500–$30,000 span. This Old House and Bob Vila both publish the lower $10–$25 per square foot, so read Fixr's band as the conservative end. Be careful with published averages on this topic: This Old House, Bob Vila and NerdWallet all trace their roughly $2,300 average back to Angi, so the apparent agreement between them is one dataset counted three times rather than three publishers agreeing.
How much mold can I clean up myself?+
The EPA draws the line at about 10 square feet, and its wording is worth quoting exactly: "If the moldy area is less than about 10 square feet (less than roughly a 3 ft. by 3 ft. patch), in most cases, you can handle the job yourself." Above that it directs you to its remediation guide. Two caveats attach: the EPA's guidance does not apply where the water came from sewage, and Bob Vila adds that it does not apply if anyone in the household has respiratory sensitivities. This is the single most useful figure on the topic, because below it the honest answer is that you should not spend anything at all — a contractor pricing a 3-by-3 patch is quoting a minimum call-out fee, not a measured job.
What is the difference between limited and full containment, and what does it cost?+
The definitions are the EPA's and they turn on affected area, not on severity. Under 10 square feet, EPA's Table 2 requires no containment. Between 10 and 100 square feet it recommends limited containment: "a single layer of 6-mil, fire-retardant polyethylene sheeting" with a slit entry and covering flap. Above 100 square feet it recommends full containment: "Double layers of polyethylene should be used ... A decontamination chamber or airlock should be constructed." Both must be held under negative pressure, and the EPA gives a field test for whether it is working — the sheeting should billow inwards. What none of that comes with is a price. The EPA publishes no dollar figures for mold work anywhere, and no cost publisher prices containment as a tier; the only containment figure retrievable is Fixr's hourly labour rate of $75–$120 plus equipment "usually under $100", with no published hour count to multiply it by. So this calculator tells you which level the EPA recommends for your area and adds nothing for it, rather than inventing a surcharge.
Does mold remediation include repairing the wall afterwards?+
No, and this is the commonest way a mold budget goes wrong. Remediation removes contaminated material and cleans the area; it does not put back the drywall, flooring, framing or cabinetry that came out. This Old House states it directly: those repairs "are often priced separately from the remediation work" — and then publishes no figure for them. The figures that do exist describe different scopes and cannot be added into one line: Fixr puts mold damage repair at $75–$3,000 "in addition to the remediation costs" and full restoration on severe problems at $10,000–$20,000, while Bob Vila puts significant damage at $2,000–$20,000. None of them is included in this calculator's total, and the page says so rather than leaving you to find out when the invoice arrives.
Does remediating the HVAC system cost extra?+
Yes, and it is the one thing that genuinely adds to a per-square-foot price, because a duct run is not a surface. Fixr, This Old House and Bob Vila all publish $3,000–$10,000 for whole-system HVAC remediation — the strongest three-way agreement in this dataset. Smaller scopes with confusingly similar names: Bob Vila prices air ducts alone at $600–$2,000, Fixr prices a single vent at $100–$500, This Old House and Bob Vila both put a radiant system at $1,500–$5,000 and a furnace or air handler at $3,000–$5,000. Establish which of those a quote actually covers before you compare two of them.
Will homeowners insurance pay for mold remediation?+
Sometimes, usually partially, and almost always with a cap that is separate from the rest of the policy. NerdWallet reports that insurers "usually cap payouts at $1,000 to $10,000" on mold specifically, with a rider sometimes available to raise it. A tenfold spread in a sub-limit is the kind of thing worth reading on your own declarations page rather than assuming from an article. Whether a loss is covered at all turns on what caused the water rather than on the cap, which is a coverage question and not a cost question — this page prices the work. One practical note that does connect the two: the $500–$700 post-remediation clearance test is the document an insurer is most likely to ask for, and it is the line homeowners most often skip.
Mold Remediation Cost Calculator is built and maintained by the RealCostIQ editorial team. Cost ranges and rates are checked against published industry data and contractor quotes, and revised when the underlying figures move. Read our data methodology or more about who builds this. Every calculation runs in your browser — no account, and none of your inputs are stored.
Cost ranges and rates here are checked against contractor quotes and published industry data. If a number still looks off, email Support@RealCostIQ.com and we'll review and fix it.