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The Best Mold Resistant Building Materials To Mold Proof A Home

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Mold growth on any structure can pose a serious problem. Being the invasive fungus that it is, mold will grow on any building material from the floor to the ceiling. If conditions are right, mold will even make a home on the basement floors and walls.

Preventing and reducing moisture inside the home is key. Preventing leaks, using humidity monitors, and running dehumidifiers are all part of a solid mold prevention strategy. But what about the building materials themselves?

My father owned a construction company and growing up I remember him talking about the transition from quality building materials to cheaper and cheaper versions of the same materials. He was and still is a smart man and he saw the mold on the walls long before building materials began to contribute to the increased problem with water damaged buildings. Shoddy construction practices are to blame as well.

High quality, mold resistant building materials are becoming more and more common to use both in new builds and in remodels and repairs.

Why? Because preventing moisture buildup inside the home with products like paperless drywall, moisture-resistant gypsum board and proper caulking can not only increase the lifespan of the home but give it an added layer of protection against mold growth.

There are two type of building materials that can play a role in your mold prevention strategy. The first are actual mold resistant building materials. The materials actually prevent mold due to how they were manufactured or what they were treated with. The second are moisture resistant building materials.  These are materials that may resist water and flooding to some degree.

The trouble with some mold resistant building materials is that they are treated with toxic chemicals. This is why it is important to look for materials that are certified by institutions that monitor environmental impact such as Greengaurd and the LEED Green Building Rating System.

The other issue lies with moisture resistant building materials. Some of these actually inhibit drying. Resistance to moisture combined with the ability of the total component to dry is an important consideration when selecting these materials. Think tile on top of plywood. Tile itself resists moisture

In both cases, choose materials based on location, their compatibility with other types of materials, and on how the total components or systems (wall, floor) drain and dry. And please, don’t settle into a false sense of security that mold resistant building materials coupled with moisture resistant building materials are protecting your home from leaks and mold. Make sure you are following all of my mold prevention tips in your home as well!

Various mold resistant building materials

Let’s take a look at the most common mold resistant building materials on the market today!

Mold Resistant Wood

Pressure treated lumber, the most commonly used wood, is sold as being resistant to rot and resistant to wood destroying insects. However, it is very often not only wet when purchased, but is often mold contaminated with several types of mold. Don’t fall for the clever marketing scam for pressure treated lumber.

Mold resistant wood is basically 2x4s that have been treated with an anti-mold fungicide. Areas of your home that can be built with treated wood include the trusses and rafters in your attic, the floor joists for the main and top floor, and the plywood exterior that lies under your siding. Another benefit of choosing anti-mold wood is that it is also resistant to termite damage.

FrameGuard® mold-resistant wood is coated wood combining a blend of anti-mold chemicals with borate technology, alleviating problems from mold, termites and decay-causing fungi. FrameGuard wood is available in framing and truss lumber, plywood, OSB, and SIPs, as well as other engineered wood products.

Frame Gaurd Mold Resistant Plywood

In addition to its mold- and pest-resistant qualities and competitive warranty, FrameGuard wood is easily identifiable due to a green colorant that is mixed with the active ingredients.

Offering a host of environmental benefits, FrameGuard wood:

  • Prevents mold growth and associated indoor contaminants, reducing the likelihood of mold-related health problems for inhabitants.
  • Protects wood without releasing harmful levels of emissions into the building as the coating is GREENGUARD Indoor Air Quality Certified®.
  • Offers protection against mold, termites and fungal decay.
  • Uses anti-mold fungicides and borates, a low impact preservative.
  • Is listed in the GreenSpec® directory of environmentally preferable products and won an NAHB Green Building Award.
  • Wood is a renewable material that requires less energy to produce than alternative building products. Wood also sequesters carbon and growing forests absorb carbon dioxide, thus reducing emissions of greenhouse gases.
  • FrameGuard® wood is produced using plentiful, fast-growing trees grown primarily in managed timberlands (not in ancient forests or unregulated tropical rain forests). Their supply is replenished in fewer years than the service life of the coated wood.
  • Wood construction often allows the use of lower impact installation equipment than construction with heavier building products.
  • Wood is an excellent insulator, conducting less heat, noise, and electrical current.
  • The FrameGuard coating extends the life of wood, reducing demands on forests and the need for replacement lumber.

You can find FrameGaurd wood here.

Mold Resistant Drywall

Mold resistant drywall

Use non paper faced gypsum wallboard, water resistant fiberglass facing gypsum wallboard or panels, or cement board. These products may provide more resistance to moisture and mold than regular dry wall faced with paper. This is because paper facing provides a food source for mold. Fiberglass facing removes the organic material making it less enticing to mold. Please know that mold resistant drywall does not completely prevent mold. It just reduces its occurrence.

The top mold resistant drywall brands are Humitek and DensArmor Plus. The easiest brand of mold resistant drywall to find is the USG Sheetrock Mold Tough Drywall.

Mold Resistant Drywall Tape and Joint Compound

Research has indicated that quick-setting joint compound and fiberglass tape may withstand leaks and flood events better than regular drywall joint compound and paper tape.

The two types of mold resistant drywall tape are:

Mold Resistant Insulation

Package of mold resistant insulation material, rock wool is wrapped in foil.

Foam or closed-cell spray foam, including extruded polystyrene or polyisocyanurate, is not damaged by water and resists surface mold growth. This kind of insulation generally allows the wall and floor systems to drain and dry when installed properly.

Fiberglass insulation inherently resists water damage and surface mold growth. However, the insulation may trap and hold water and slow drying time of wall and floor systems. In addition the panels of insulation are easily filled with organic materials that provide food for mold.There are some companies that are treating fiberglass insulation with a fungicide.

Nu-Wool manufactures a premium cellulose insulation that is treated with a fungicide approved by the EPA and is very low in toxicity. This would be my top choice for insulation.

Mold Resistant Paint

I wrote an entire post about mold resistant paint including brands I recommend so you might want to give that a read. But in short, more brands of paint are offering low VOC paints that contain fungicides. Using mold resistant paint on walls discourages the growth of mold on those painted surfaces. However, if there is already mold on the wall you can’t use the mold resistant paint to kill the mold.

Mold Resistant Carpet

Mold Resistant Carpet - black and white berber

While I don’t encourage the use of carpet since it easily traps mold spores and gives them plenty of organic material to grow on, if you must use carpet then go with a polypropylene carpet. The fibers in the carpet offer a little more resistance to mold growth than other carpets.

If you have carpet and are dealing with carpet mold, you might want to check out my post on how to remove mold from carpet.

Mold Resistant Caulk

Again, I wrote an entire post about mold resistant caulk. The post itself is pretty fun too! I think you will enjoy it.

Mold Resistant Grout

Broken record time. I wrote an entire post about mold resistant grout. This is a pretty short post so go give it a quick read.

Mold Resistant Sealants

A mold resistant sealant is basically a protective coating that can be applied to most any surface in the home. This sealant is blended with anti-microbial chemicals. There are specific sealants for the various building materials.

Here are a few of the mold resistant sealants I have used:

Endurance Bio Barrier

Endurance BioBarrier

Endurance Bio Barrier™ formulas are revolutionary water-based coatings that have been laboratory and military tested and proven to inhibit the growth of molds, mildew, and germs on the film of the treated surfaces. Our mold inhibitor products are the perfect mold prevention solution for homes, vehicles, boats, schools, manufacturing and institutional environments. Effective when both wet and dry, this liquid may be applied on virtually any surface. Formulated with zero VOCs (Volatile Organic Compounds) making it safe for your home and the environment.

Endurance Bio Barrier™ inhibits biological growths meaning that it prevents mold and odors for up to 6 months on flooring and bathrooms, 2 years on walls and ceilings, and up to 25 years in enclosed areas such as stud cavities, guaranteed!

You can read my entire Endurance BioBarrier Review post here.

Check the current price and purchase Endurance Bio Barrier here.

Wasp Botanical Antimicrobial Clear Mold Resistant Sealant

WASP Antimicrobial resistant sealant

Ready-to-use, Wasp™ surface anti-mold and antimicrobial sealer made in the US,  25(b) safe ingredients according to EPA’s (Environmental Protection Agency) federal insecticide, fungicide, and Rodenticide Act (FIFRA) under minimum risk exemption regulation in 40 CFR 152.25(f).

Wasp™ delivers long-term, interior and exterior anti-mold surface protection. Easy to apply with a brush, roller, spray, or paint sprayer. Quickly penetrates and adheres to porous and non-porous surfaces and leaves a durable, long-lasting barrier that will not blister, peel, crack, or chip, while helping to restore the integrity of water damaged materials.

  • Long lasting anti-mold sealant on exterior concrete, brick, stucco, roofing tiles and masonry materials.
  • Long lasting anti-mold sealant for interior mold remediation crawl spaces and open chases.
  • Long lasting anti-mold treatment for ducts

You can purchase WASP here. Save 5% off your purchase with coupon code PRIME5.

Foster® 40-51 Sheer Defense® Mold Resistant Clear Sealer

Sheer Defense® resists the growth of mold on its surface. It is formulated with EPA registered additives and provides a water-resistant finish that is both flexible and crack resistant.

Foster® 40-60 Drip Pan Coating

This coating is for the protection of metal drip pans used in HVAC systems. The surface of Foster® 40-60 is resistant to the growth of fungus, bacteria and mold. Foster® 40-60 provides vibration dampening and will bond to clean, bare metal without the use of primers.

Mold Resistant Shower Pan

The shower pan is a waterproof barrier that is formed into the shape of a pan. It’s placed under the tile floor of a shower. The purpose of the pan is to catch any water that may seep through the tile and grout and direct it to the drain.

Tile Redi Shower Pan

TileRed produces a shower floor that is ready for tile and is set on the shower pan floor with epoxy. This product is guaranteed to be leak free and mold resistant. No further waterproofing is required when using this most resistant shower pan.

You can learn more about TileRed or make a purchase here.

Mold Resistant Stucco

Mold resistant stucco is pre-blended with a waterproofing and anti-microbial product. It is easily found at any home improvement store. Amerimix is one of the more readily available brands.

You can learn more about Amerimix here.

Now that you’ve learned more about which building materials to use in your home, let’s take a look at some other materials that aren’t mold resistant per say but that do help prevent moisture or reduce moisture.

ZIP System ® Wall Sheathing, Roof Sheathing, and Flashing Tape

The ZIP System is a one-of-a-kind structural roof and wall system with a built-in energy-efficient barrier that keeps moisture out and reduces air leakage, while still allowing panels to properly dry.

This revolutionary roof and wall system streamlines weatherization with an integrated air and water resistant barrier. The ZipSystem eliminates housewrap, has a built in barrier that won’t blow off or tear, and has moisture breathability.

ZIP SystemTape is made of an advanced acrylic adhesive, which creates a superior airtight and watertight seal that withstands harsh weather in both roof and wall applications. The tape is quickly and easily applied by hand. ZIP System Tape is ideal for both seam sealing and flashing.

ZIP System Sheating and Tape

Key Features and Components of ZIP System® Sheathing and Tape

  • High quality structural sheathing panel made of engineered wood delivers strength and durability.
  • Built-in vapor permeable water-resistive barrier eliminates the hassles of house wrap and felt. Engineered for enhanced drainage of bulk water and optimal permeability to allow water vapor to pass through and promote drying.
  • A continuous, rigid air barrier decreases unwanted air leakage for greater energy efficiency.
  • ZIP System™ tape with a specially engineered, high performance acrylic adhesive bonds with ZIP System® panels for a permanent protective seal.

You can learn more about the ZIP System at the Huber Engineered Woods website.

Moisture Resistant Wall Materials

The following types of moisture resistant wall materials can be considered.

  • Steel studs, beams, and sill plates. These should be treated with a waterproofing sealant to resistant corrosion.
  • Solid naturally decay-resistant wood
  • Cement board
  • Brick
  • Cast stone with waterproof mortar
  • Structural glazed clay tile
  • Ceramic veneer or ceramic wall tile
  • Porcelain wall tile
  • Concrete
  • Glass blocks or glass panels
  • Natural solid or veneer stone with mold resistant grout
  • Artificial non-absorbent solid or veneer stone with mold resistant grout

Moisture Resistant Flooring Materials

The following types of moisture resistant flooring materials can be considered.

  • Concrete materials such as concrete tile or pre-cast concrete
  • Latex or bituminous formed-in-place flooring can be colored, polished, and sealed
  • Non-porous stone, slate, or cast stone with waterproof mortar
  • Clay tile, quarry tile, terrazzo, ceramic tile, or porcelain tile
  • Rubber sheets or tiles
  • Naturally decay-resistant wood subflooring (redwood, cedar, some oaks, bald cypress). If there is a water intrusion, unless the finished flooring is removed immediately to allow the subfloor to dry, it may become damaged and moldy.
  • Steel subflooring
  • Solid plastic lumber (weird I know and it may inhibit drying of other materials)

Other Moisture Resistant Building Materials

  • Corrosion-resistant metal, metal clad, and vinyl window frames. The rough opening of a window should be prepared with housewrap and pan flashing, and a sill pan should be used.
  • Interior metal or fiberglass doors
  • Corrosion-resistant metal exterior doors
  • Exterior fiber-cement, vinyl, or aluminum siding, brick, cinderblock, or concrete. Brick, cinder block or cement block must have drainage provided so that water and moisture vapor behind the material can drain and dry.
  • Metal cabinetry
  • Corrosion-resistant hinges and galvanized or stainless steel nails

Remember, all the mold resistant building materials in the world won’t work unless you are practicing mold prevention! Mold resistant products + leak prevention + mold prevention = a mold proof home.

Various mold resistant building materials in a hardware store

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10 Comments

  1. Hempcrete is a great one to add!

    1. Thank you!!! I will add that one.

      1. What are your thoughts on Steel beams for construction and going wood free on the home Construction. Curious your thoughts or earth materials and mold resistance – such as metals, glass, and stone.

        1. Metals are fantastic in terms of their mold-resistance. However, they amplify EMFs so if you are someone who is super sensitive to those and/or your home is in a saturated area (think next to a substation or a military facility) then this might be problematic. Stone/brick/cinder block are also great in terms of their mold resistance provided they are done correctly and maintained. Outdoor mold can grow on stone and concrete so maintenance is important. In additional, a lot of people still put drywall over the stone on the inside of the house. So that is still a mold risk. Glass is probably the most troublesome seeing it needs to be properly sealed and framed in. I see a lot of moisture intrusion in home with a lot of large windows and floor to ceiling style windows.

  2. Mackenzie says:

    Thank you for your detailed and knowledgeable posts. I have CIRS and have moved more times than I can count in the last few years due to mold (WDB). I will be building a house in the near future, and I was wondering if you could answer this question to the best of your knowledge: is it preferable to build a two-story house (no basement) to have at least one level up away from the moisture-containing ground? OR can a one-story house (with concrete foundation on grade) be just as healthy, even though you are on ground level 24/7 with more spores coming in and potential for moisture to seep in? I would really appreciate any input, as my health practitioners aren’t very informed on mold prevention building practices. THANK YOU!

    1. Hi Mackenzie! There is no right or wrong answer here as it depends on the climate you live in, the type of soil you are building on, whether you have a high water table or not, if you live uphill or downhill, etc… In general, two story homes open you up to a greater potential for moisture intrusion and mold. One story homes are much easier to practice good mold prevention in. Slab on grade isn’t the worst case scenario provided it is done correctly. The concrete needs to be sealed. The thicker the pour the better. Raised floor construction with a crawlspace has a different set of issues but typically is the better option. However, you need to make sure that your contractor REALLY knows how to construct a proper crawlspace. Avoid carpet at all costs. Doors and windows need to be framed and installed properly. That is where a lot of moisture intrusion comes in regardless of the type of foundation. In addition, the foundation MUST be level so the frame of the house sit tight against it. You would be surprised how big of an issue this is. Blows my mind that contractors are “ok” with gaps between the foundation and the frame. Sigh.

  3. Wow! What a great and informative page. Thank you for this!
    My family has a lot of issues with mold, to the point where normal levels of mold bother us. We are about to build a home and have a lot of options for materials to use. The biggest question I have right now that I really hope you can help with is whether or not to build with standard building materials (wood, etc.) or to go with a metal building and then put paperless drywall in it, etc.? I am leaning more toward a metal building, but my concern with a metal building is condensation. So I was hoping you could shed some light on that. Do metal buildings tend to form condensation with changing temperatures? And if so, does this frequently lead to mold growth? Is there a material to pair the metal with that would discourage mold growth the most? Is there a certain thickness/gauge of metal sheeting that is less likely to have condensation/ allow mold growth? Also, which flooring is the best of all of the hard flooring options for discouraging/preventing mold growth? Any info you can provide on this would be tremendously appreciated!

    1. Hi Heather! Metal buildings are not my area of expertise. I suggest you reach out to Matt Risinger. He is an expert in this area. https://risingerbuild.com/

      Porcelain tile will be your best option for flooring, paired with grout that has a mold inhibitor added into it.

  4. Tom Neidecker says:

    Thank you for this article. Do you know any architects with experience designing mold resistant homes? I am looking for an experienced architect in this area. Are you familiar with “breathable walls” to reduce mold and allow the wall spaces to stay dry?

    1. Hi Tom! Somehow your comment was marked as SPAM. I always check at the beginning of each month so as to not miss anything. So sorry! Yes, I am familiar with breathable walls but unfortunately most contractors are not. https://risingerbuild.com/ is your best best for finding an architect to design a mold resistant home.