House attic mold is one of the most “popular” items in my property inspection reports. And now is time for an explanation of how to kill mold and / or how to clean mold in the attic. But before I do that, let me give you a little advice, something to consider before you sign a few (if you’re lucky) thousand dollars contract agreement with a mold remediation company.
Attic mold remediation TIP – an alternative (to consider):
Let us assume that you are in the middle of a real-estate transaction, and the home inspector just revealed to you, that your entire house attic is contaminated with mold.
If you have a brand new roof, you can only blame yourself or try to blame the roofing contractor for not checking the attic before replacing the roof (he will laugh at you unless you’ve actually asked the guy to check the attic before the roof replacement). If you have an older roof, the importance of this advice is even greater.
Call at least 2-3 mold remediation services for an estimate – specify to the representatives, that you not only want to have the mold removed, but also attic ventilation system corrected / installed if necessary / ask if the attic insulation requires replacement.
With the numbers from the mold remediation contractors, call 2-3 roofing contractors, and ask them for a quote on the roof replacement cost including decking boards / plywood (ask the roofer to check the attic area), attic ventilation improvement, and insulation if necessary.
Be cautious if they only suggest humidistat controlled power vent installation – without properly functioning soffit vents or any type of vents along the lower portion of the roof this might not be an adequate solution.
If the attic insulation replacement is not required (it most cases it will not be possible to tell without laboratory testing), make sure it’s sealed with plastic foil before the roof and its decking replacement. Fold the foil sealing its contents after the contaminated decking has been removed, and dispose of as a regular waste (EPA recommendation).
If you only have a small area of attic contaminated with mold, the roof replacement option would be more expensive. But with an entire attic that needs mold remediation, it might be cheaper (or even much cheaper) to remove all contaminated decking, install completely new roof and correct ventilation issues.
I have seen $3,000.00 – $10,000.00 invoices for the attic mold remediation process in approximately 1000 square feet of attic area.
Benefits of the roof / decking replacement over the mold removal:
- roof and decking replacement might be cheaper than cleaning of an entire attic contaminated with mold
- the real-estate transaction killing mold is gone
- attic ventilation improvement is much easier during the roof replacement and often handled with no significant / additional cost
- the buyer gets a brand new roof
Even if the roof replacement price is slightly higher than the mold remediation process, it is still worth to take it under the consideration because you are gaining a valuable house update (new roof), that will be disclosed on a real-estate listing.
In some cases, the roof decking and framing are contaminated, and replacement of the decking only would not entirely solve the problem. In such case, you’d have to clean contaminated joist or trusses.
How to kill mold and how to clean mold in the attic.
This is not a mold killing or mold cleaning case study, it is just an explanation based on my observations and EPA (Environmental Protection Agency) recommendations.
Even if you are dealing with a small contaminated attic area – 10′ x 10′ is the maximum area recommended by the EPA to be treated by non-professionals, forget about killing mold with spraying it with bleach or other disinfectants. It ‘s been confirmed by laboratory testing that it does not kill all of the spores and in most cases you’ll be just making a mess.
The best way to kill the attic mold (just like any other mold) is to remove it from the surface it’s growing on, or remove the contaminated surface!
EPA recommends four mold cleanup methods and all of them can be applied in the attic, assuming that it is a small area (up to 10 sq. feet).
- You can clean the surface by using a wet vacuum – the type you can fill its tank partially with water to contain mold residue from the contaminated surface
- Wipe the surface with a damp sponge or rag – use clean water or wood cleaner
- Use high efficiency HEPA vacuum cleaner on thoroughly dried surfaces, and dispose of the picked-up contents in well-sealed plastic bags
- Remove all contaminated material, seal it in plastic and dispose of as a regular waste. They recommend using HEPA vacuum after this, but in the attic you’d most likely have to remove the floor insulation (if contaminated). You can also cover the insulation with plastic foil, and fold the foil sealing its contents after the cleaning process.
You may or may not have any allergic reactions to mold. However, always use protective equipment, especially in the attic area where you are exposed to the insulation fibers and dust.
As a minimum protection during the mold removing procedure EPA recommends: Gloves, N-95 respirator and eye protection (preferably fully enclosed goggles). As an additional protection you can add half face respirator or full face respirator with HEPA filter, disposable full body clothing, head gear, and foot coverings.
How to clean mold if large section or an entire attic is contaminated
I personally wouldn’t even attempt to do it myself, so my suggestion is:
Use a professional mold remediation company:
- check their background and check it manually by calling their clients
- ask for clients who had their attic mold remediated approximately 1 year ago – it usually takes a winter for the mold to start growing again if the job wasn’t fully completed
- Insist on removing the mold completely instead of encapsulating it (Media Blasting methods give the best results).
- Encapsulation is simply a process of covering the mold contaminated surface with paint (paint like product) that contains (or at least some of them do) mold killing chemicals
If your attic mold is properly removed and all of the issues responsible for its growth corrected, which is even more important than mold removing, it will not re-grow / no need for encapsulating.
- Hire a different contractor for mold testing and mold remediation to eliminate conflict of interest.
- Make sure that you perform an independent clearance test after the mold remediation process completion.
- Clearance test is to determine if there are any mold spores remaining in the previously contaminated area
Extremely important – examine the attic (or have somebody do it for you) after the mold cleaning procedure is finished.