Foundations and interiors
Mold inspection and remediation
Mold inspection, mold removal, attic and basement mold remediation, crawl space treatment and indoor air quality testing for homes and small buildings across Canada and the US. Request a free quote online. For homeowners, landlords and property managers. Quote requests by email.
What's covered
- Mold Inspection & AssessmentAn inspection covers the places where mold usually starts: basements, attics, bathrooms, around windows and under sinks. Moisture meters, and sometimes a thermal camera, help find damp spots behind finished surfaces. The result should be a clear picture of the affected areas, the likely moisture source and what the cleanup needs to include, so the quote is based on what is actually there.
- Mold Removal & RemediationRemediation means physically removing the mold, not painting over it or spraying it and walking away. The work area is closed off with plastic sheeting and kept under negative air pressure so spores do not spread to the rest of the house. Badly affected porous materials such as drywall, insulation and carpet are cut out and bagged. Wood and concrete are cleaned, HEPA vacuumed and sometimes sanded. The area is left clean and dry before anything is rebuilt.
- Attic Mold RemovalAttic mold usually shows up as dark staining on the underside of the roof sheathing, often heaviest on the north side. The cause is almost always warm, humid air from the house leaking into a cold attic, combined with blocked soffit vents or bathroom fans that vent into the attic. Sheathing can be cleaned by scrubbing, sanding, or soda or dry ice blasting. Unless the air leaks and the ventilation are fixed, the mold comes back.
- Basement Mold RemovalBasements stay cool and often damp, which makes them the most common place for mold in a house. Finished basements can hide it behind drywall, carpet and insulation for years. Removal usually means opening up the affected walls, taking out wet materials, cleaning the framing and concrete, and drying everything before it is closed up again. The quote should also say where the water comes from: a foundation leak, condensation or a plumbing problem.
- Crawl Space Mold TreatmentCrawl spaces with bare dirt floors and open vents often run at high humidity, and mold grows on the joists and the underside of the subfloor. Treatment means cleaning the wood, removing wet insulation and debris, then controlling the moisture with a vapour barrier, sealing, or a dehumidifier. Air from the crawl space rises into the living space, so this matters for the whole house.
- Mold After a Leak or FloodMold can start growing on wet drywall, carpet and wood within a day or two. After a leak or a flood, the priority is drying the structure properly with air movers and dehumidifiers and removing materials that cannot be dried. If mold has already started, affected materials are removed under containment. If you are making an insurance claim, ask for photos and a written scope you can send to your adjuster.
- Indoor Air Quality & Mold TestingTesting is useful when you smell mold but cannot see it, when someone in the house has symptoms, or to confirm that a cleanup worked. Indoor air samples are compared with a sample taken outside, and swabs or tape lifts show what is growing on a specific surface. The samples go to a lab for analysis. Testing does not replace an inspection, and when mold is plainly visible it is often not needed before removal.
- Moisture Control & PreventionMold needs moisture, so lasting results depend on what happens after the cleanup. Depending on the cause, that can mean a dehumidifier in the basement, bathroom fans vented outside, better attic ventilation and air sealing, a vapour barrier in the crawl space, or fixing grading and downspouts. The quote should list the mold removal and the moisture fix separately so you can see the cost of each.
How the work is handled
- Moisture Source FirstMold grows because of a leak, condensation or poor ventilation. The inspection looks for that cause, and the quote says how to deal with it.
- Contained WorkDisturbing mold releases spores. Plastic sheeting, negative air and HEPA filtration keep them out of the rest of the house.
- Removal, Not Cover-UpPainting over mold or spraying it and leaving does not solve anything. Damaged materials come out, and what stays is cleaned.
- Written ScopeAffected areas, materials to remove, containment, drying, any testing and the rebuild, all written down before work starts.
- Homes and Small BuildingsSingle-family homes, condos, duplexes, triplexes, small apartment buildings and small commercial properties.
- Form Only, Your PaceSend the details when it suits you. Nobody calls you before you ask for a quote.
By climate
- Long, cold winters with heavy snow and a short, warm summerSnowmelt in spring soaks foundations, and warm indoor air meeting cold attic sheathing leaves frost that turns to mold by March. Ask for moisture readings in the basement and attic, and plan remediation for spring when the source of water can be traced and fixed.
- Wet maritime weather, salt air, many freeze-thaw cycles and storm-driven rain and snowDamp sea air, storm rain and constant freeze-thaw keep basements and crawl spaces wet for long stretches. Remediation only lasts if the moisture source is handled too, so ask whether the quote includes drying, dehumidifying and checking grading and foundation leaks.
- Four seasons: humid summers, cold winters with snow and repeated freeze-thawHumid summers raise moisture in basements while winter condensation forms on cold walls and attic nails. Mold often shows up in two seasons for two different reasons, so ask the inspector to explain the cause and the prevention steps, not just the cleanup.
- Hot, humid summers, mild winters, heavy storms and in coastal areas hurricanes; pests and mold all yearMold grows almost year round, and after a storm or flood it can spread within days. Fast drying is the priority, so ask how soon the team can start, how they contain the work, and what humidity control they recommend for the home afterward.
- Desert heat, strong sun and UV, dust, monsoon downpours, very little freezingDry air keeps most homes mold free, so growth usually points to a hidden plumbing leak, a cooler drip or a roof leak from monsoon rain. A good inspection traces that one water source, and the quote should cover repair coordination as well as removal.
- Dry, high-altitude climate with strong UV, big day-night swings, snow and freeze-thawLow humidity limits mold, but ice dams, snowmelt leaks and attic condensation in cold snaps create pockets of growth. Ask for an attic and basement check after a hard winter, with a moisture map showing exactly where water got in.
- Mild, wet marine climate: long rainy seasons, moss and moisture, little hard freezing near the coastLong rainy seasons and mild temperatures keep crawl spaces, attics and window frames damp for months. Ask about vapor barriers, ventilation and dehumidifiers along with removal, since mold tends to return quickly when the space never gets a chance to dry.
- Dry summers and wet winters, wildfire smoke and ash, earthquakes, almost no snow on the coastDry summers hide problems, then the first winter rains expose roof and window leaks that feed mold in walls. Smoke and ash can also get into ducts, so ask whether the inspection covers air quality and leak tracing before any removal work.
- Extreme cold, permafrost in places, very short building season and remote freightTightly sealed homes with long heating seasons trap moisture from cooking and showers, and condensation forms on cold walls and windows. Ask about ventilation and air exchange as part of the fix, and plan work around access since specialists may need to travel in.
Every written quote covers
- Where the moisture comes from
- Areas and materials to remove
- Containment and air filtration
- Drying and cleaning steps
- Testing, if any, and why
- What gets rebuilt afterward
Questions
Can I clean mold myself?
Small patches, under about 10 square feet (1 square metre), on hard surfaces like tile, a window frame or a shower caulk line can usually be cleaned with soap and water while wearing gloves and a mask. Larger areas, mold inside walls, in insulation or in the attic, or mold that keeps coming back are worth having assessed. Bleach is a poor choice on drywall and wood: it does not reach into the material and it adds moisture.
Is black mold dangerous?
Many molds look black, and colour alone does not tell you the species or the risk. Any mold growing indoors can irritate the eyes, nose and lungs, and it is a bigger concern for people with asthma, allergies or weakened immune systems, young children and older adults. The approach is the same whatever the colour: fix the moisture and remove the mold safely.
Do I need mold testing?
Not always. When mold is visible, the inspection and moisture readings usually tell you what you need to know, and testing adds cost without changing the plan. Testing is useful when there is a musty smell but nothing visible, when someone in the house has health concerns, during a home sale, or to confirm that a cleanup worked.
How much does mold removal cost?
It depends on the size of the affected area, where it is (an open basement wall is easier than an attic or a crawl space), how much material has to be removed, the containment needed, any testing, and what has to be rebuilt afterward. A small bathroom job and a full attic are very different projects. The only reliable number is a written quote after an inspection.
Why does mold keep coming back after cleaning?
Because the moisture is still there. Attic mold usually comes from warm, humid air leaking out of the house and poor attic ventilation. Basement mold comes from foundation leaks, condensation or high humidity. Unless the source is fixed, cleaned surfaces get recolonized. A proper quote covers both the removal and the moisture problem.
Can we stay home during mold removal?
Usually, yes. The work area is sealed off with plastic and kept under negative pressure, so air is drawn out through filters instead of into the house. For large jobs, or if someone in the home has a respiratory condition, you may prefer to stay elsewhere for a day or two. The specialist can tell you what to expect for your job.
Do you handle condos, rentals and small commercial buildings?
Yes. Owners of condos, duplexes, triplexes, small apartment buildings and small commercial properties are welcome to request a quote. Mention the building type and whether tenants live there so the right specialist reviews it.
How do I get a quote?
Email us your city, the service you think you need, and what you are seeing or smelling, including where it is and roughly how big the area looks. A specialist who works in your area follows up to set up an inspection. Requesting a quote is free and there is no obligation to go ahead.
Cities
British Columbia
New Brunswick
Newfoundland and Labrador
Northwest Territories
Nunavut
Ontario
Prince Edward Island
Quebec
- Laval
- Terrebonne
- Mascouche
- Repentigny
- Blainville
- Boisbriand
- Sainte-Thérèse
- Mirabel
- Saint-Eustache
- Deux-Montagnes
- Montréal
- Plateau Mont-Royal
- Outremont
- Westmount
- Mont-Royal
- Saint-Laurent
- Anjou
- LaSalle
- Verdun
- Pointe-Claire
- Dollard-des-Ormeaux
- Kirkland
- Beaconsfield
- Dorval
- Rosemont
- Longueuil
- Brossard
- Boucherville
- Saint-Hubert
- Québec City
- Gatineau
- Sherbrooke
- Trois-Rivières
- Saguenay
- Lévis
- Saint-Jérôme
- Drummondville
- Rosemère
- Bois-des-Filion
- Lorraine
- Sainte-Anne-des-Plaines
- Sainte-Marthe-sur-le-Lac
- Oka
- Pointe-Calumet
- Saint-Joseph-du-Lac
- Charlemagne
- L'Assomption
- Saint-Sulpice
- Lachine
- Montréal-Nord
- Saint-Léonard
- Mercier–Hochelaga-Maisonneuve
- Ahuntsic-Cartierville
- Villeray–Saint-Michel–Parc-Extension
- Le Sud-Ouest
- Côte-des-Neiges–NDG
- Ville-Marie
- Pierrefonds-Roxboro
- Rivière-des-Prairies–Pointe-aux-Trembles
- L'Île-Bizard–Sainte-Geneviève
- Côte-Saint-Luc
- Hampstead
- Baie-D'Urfé
- Sainte-Anne-de-Bellevue
- Senneville
- Montréal-Est
- Montréal-Ouest
- Saint-Lambert
- Saint-Bruno-de-Montarville
- La Prairie
- Candiac
- Sainte-Catherine
- Saint-Constant
- Chambly
- Carignan
- Saint-Basile-le-Grand
- Beloeil
- Mont-Saint-Hilaire
- Varennes
- Vaudreuil-Dorion
- L'Île-Perrot
- Pincourt
Yukon
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Colorado
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Delaware
District of Columbia
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Massachusetts
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Mississippi
New Hampshire
New Jersey
New Mexico
Oklahoma
Pennsylvania
Rhode Island
South Carolina
South Dakota
Tennessee
Texas
Utah
Vermont
West Virginia
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