Mold and Indoor Air Quality Testing for Rental Properties
A tenant reports a musty smell, a stain or symptoms that will not go away. You have cleaned, replaced filters and maybe bought an air purifier, and the complaints keep coming. We find the cause in the building and put it in a written report you and your tenant can both read.
The calls we get from rental owners.
These are the situations we hear most, and where each one usually leads.
A musty smell, nothing visible
Usually a moisture question first. We take moisture readings and look for wet material behind finishes, then sample the air if it will add something.
A stain or spots on a wall or ceiling
A stain shows where the problem appears, not where it starts. We trace the water back to its source and mark how far the wet material goes.
Headaches, a stuffy nose or a sore throat
Symptoms can have several causes. We look at moisture, humidity, ventilation and the HVAC together, along with sources such as new materials, stored chemicals and combustion appliances.
A test came back clean, the complaints continue
One air sample shows one day. A good air result does not rule out wet material in a wall. We go back to the building and look for the moisture.
Find the moisture first. Then test.
Duct cleaning, carpet cleaning and an air purifier treat the air. If water is getting into a wall, a roof, a window or a chimney, the problem comes back. Many indoor air complaints start with moisture, so that is where we start.
- A short questionnaire first. Where symptoms are part of the complaint, we send a short questionnaire before the visit, so we know which rooms and which history to look at.
- Infrared and meters. A FLIR MR277 combines a thermal camera with pin and pinless moisture readings, to find wet material behind finishes without opening walls.
- A look behind finishes. A borescope through a small opening where the readings point behind a wall, a tub or a shower.
- Humidity and dew point readings room by room.
The right test for the complaint.
We only sample for what the walkthrough points to. When odors or symptoms point past mold, that can mean VOC and formaldehyde sampling, or surface samples for soot after a furnace puff-back. Samples travel under chain of custody to accredited laboratories.
Indoor air samples
Spore trap air samples in the rooms of concern, to see what is in the air in the unit.
An outdoor control
An outdoor sample taken the same day, so the indoor results are judged against the air outside.
Inside the air handler
Every room's air passes through the same system, so one dirty duct can explain a complaint that seems to come from everywhere.
At the supply register
Growth on a register is a sign to look further upstream, into the duct and the air handler.
Fix what the readings show. Nothing more.
The readings set the scope. Drywall and other porous materials are read as wood moisture equivalent (WME). Wood framing is read as moisture content (MC). This is the scale we report against.
A written record you can share with your tenant.
Every Prescient report follows the same structure, so a reader can find the answer fast and a contractor can price the work from it.
Plain summary
What we found and what we recommend, in plain English, at the top.
Findings and photos
Room by room, with moisture readings, humidity, photos and the moisture map.
Lab results
The results compared to the outdoor control, interpreted by an industrial hygienist.
Recommendations
In plain English: moisture repair, ventilation, cleaning, HVAC work or further investigation.
A phone walkthrough
We walk you through what the report means and what to do next.
Retesting
After the repair, an independent post-remediation verification with moisture readings and air samples.
Findings your tenant hears from someone with nothing to sell.
We do not sell remediation or repairs. The result does not change what we earn, so the findings are the same whoever reads them.
- Measurements, not opinions. Readings, photos and lab results your tenant can see for themselves.
- Neutral wording. We report what we measured and observed, with no blame on anyone.
- The building, not the diagnosis. We are not physicians and we do not make medical judgments. If symptoms are part of the picture, the tenant can share the report with their doctor.
Quick to site, quick to paper.
Call
The phone call is free. Tell us what the tenant reported and what has been tried. We quote it on the call.
Lab results
Typically 24 hours for mold samples at an accredited lab.
Report
Within two business days of receiving the lab results. A 24-hour rush is available.
For rental owners.
My tenant already had a mold test and nothing was found. Why test again?
An air sample shows one day in one spot. If the complaints continue, the next step is usually the building itself: moisture readings, infrared and a look at the HVAC. We tell you on the call whether more sampling would add anything.
Can you tell me whether the symptoms come from the house?
No. We are not physicians and we do not make medical judgments. We measure what is in the building, identify likely sources and recommend fixes. The tenant can share the report with their doctor if symptoms are part of the picture.
Do you always take air samples?
No. If the readings and the visual inspection answer the question, we tell you whether sampling would add anything.
Will you open walls?
Only where the readings point to it, and only as much as it takes to see. Most of the work is done with meters, infrared and a borescope before anything is opened.
Do you do the repairs or the mold removal?
No. We only inspect and test. That keeps the findings independent, and the report tells your contractor exactly what and where.
I own more than one rental. Can you keep an eye on a unit?
Yes. Our home mold testing subscription is four air quality visits a year at one fixed annual price, with a written report each quarter.
Where do you work?
Rental homes in Maryland and Northern Virginia, within about an hour of our Silver Spring office.
A tenant complaint that will not go away? Call us.
Weekdays 8 to 5. Tell us what the tenant reported and what has been tried, and we will quote it on the call. Maryland and Northern Virginia.