Please dont pay for a Borate spray unless the buyer wants to pay for it. To achieve this, Acceptable Solution E2/AS1 says that, on near-level sites, the floor level must be no less than 150 mm above the crown of the road or the lowest point of the boundary. How Timber Reacts To Moisture. The chart below will clear things up. If low WMC readings were obtained during the winter, and other signs of high moisture levels are present, obtain additional readings during the summer. I am having a section of our 3.25 Maple hardwood floor replaced. Moisture contents of 12 to 17% is ok. You dont want to see any subfloor reach about 25% which is where mold will start to grow. If the wood would really arrive with a MC of 14%, we would not have any problems. The flooring pieces should be removed from the packaging to allow the ambient conditions to equalize the wood. The acceptable moisture levels of wood and lumber are in the range of 6% to 8% for interior and 9% to 14% for exterior wood or for building envelope components within constructed assemblies. They are putting desiccants in the container to absorb the moisture but we feel its going to be a long time enclosed in the container without any air circulation. Furniture grade wood is typically dried to a target of 6%-9%. I suggested replacing my dehumidifier (Sears brand, bucket collection) which has been inoperable this past year. Interior walls non-insulated at around 7-8% mc. i also drilled into the wood every few inches, several inches deep with a typical drill bit. What are acceptable ranges of moisture for composite materials like MDF and Plywood, for indoor furniture use? Your contractor may use something called a moisture meter to see what the approach should be for joist damage, or it may be more obvious based on the appearance of the wood. board will move twice as much as a 4-in. The wood scale provides accurate, quantitative readings of moisture over the range of 5% to 30% MC in wood. Like all wood materials, I-joists are susceptible to moisture. Wood Handbook: Wood as an Engineering Material, https://research.cnr.ncsu.edu/blogs/wpe/files/2016/08/Equilibrium-Moisture-Content-of-Exterior-Wood-in-the-US.pdf, https://www.wagnermeters.com/shop/orion-950-smart/, http://www.csgnetwork.com/emctablecalc.html, https://www.spikevm.com/calculators/logging/equilibrium.php, https://www.wagnermeters.com/shop/orion-910-deep/, https://www.google.com/search?source=hp&ei=j6WRW76_NdmT0PEPkN29kAc&q=wood+moisture+content+and+mold&oq=moisture+content+and+mold&gs_l=psy-ab.1.0.0i22i30l3.8963.15970, Restoration Expert Says Moisture Management Critical to Health of Any House or Building, Correct Moisture Content: Critical to Your Woodworking Projects, Mckinleyville Middle Schoolers Learning about Wood Moisture Content, Ambient Data Loggers: Peace of Mind in a Box for Wood Flooring Installers, 5 Things Not to Do When Measuring Moisture in Wood Flooring, Alabama Wood Crafters Share Wood Woes When Overlooking a Moisture Meter. Do you agree with this? It constantly absorbs and releases vapour into the . Why You Should Use Relative Humidity (RH) Testing, Flooring, Millwork, Furniture & Cabinet Manufacturers, How to Choose a Moisture Measurement System for Your Sawmill Buying Guide, Acceptable Moisture Levels in Wood Knowing the Moisture Content, Free Download 5 Ways Pinless Moisture Meters Save You Time and Money. 11 0 obj << /Linearized 1 /O 15 /H [ 1017 209 ] /L 26721 /E 14333 /N 2 /T 26383 >> endobj xref 11 18 0000000016 00000 n 0000000724 00000 n 0000000820 00000 n 0000000963 00000 n 0000001226 00000 n 0000001393 00000 n 0000001566 00000 n 0000001771 00000 n 0000002827 00000 n 0000002934 00000 n 0000004271 00000 n 0000005322 00000 n 0000005517 00000 n 0000007871 00000 n 0000007949 00000 n 0000009756 00000 n 0000001017 00000 n 0000001206 00000 n trailer << /Size 29 /Info 10 0 R /Encrypt 13 0 R /Root 12 0 R /Prev 26373 /ID[<2277e06d91c56aa37caf41071ab29f47><2277e06d91c56aa37caf41071ab29f47>] >> startxref 0 %%EOF 12 0 obj << /Type /Catalog /Pages 9 0 R /PageMode /UseThumbs /OpenAction 14 0 R >> endobj 13 0 obj << /Filter /Standard /V 1 /R 2 /O (D+K\r,s\n?$+%{Nhjp-!) For wide-width solid flooring (3 or wider), there should be no more than a 2% difference in moisture content between properly acclimated wood flooring and subflooring materials. The front of the . Fungus loves wet wood. He wants to install his companys system, seal all external openings around connections, etc. What do you recommend the reader to be at before insulation and drywall on new construction? I-joists are comprised of top and bottom flanges, which resist bending, united with webs, which provide outstanding shear resistance. The best way to do this is to use an accurate moisture meter. I would like to rip two slabs and glue them together to make a nice large dining room table. I so appreciate your treatise on this issue. : Mold & Fungus In the Crawlspace. I have seen home built in the dead of winter, covered in snow, and still dry out enough for a successful home build. Thanks for the reply. . Any suggestions .thanks. hj0Ed=h].J-)_q},jR3$\ eH"wCk)E)J8 Mold starts to grow in the mid to high 20 percent moisture contents. As a result, the normal moisture meter reading for these materials in between 0.5% and 1%. Replaced the subfloor, which is . One of our new line of moisture meters will help locate areas of high moisture, if it still exists. Box 1437 For example, if the expected EMC ranges from a low of 6% to a high of 9%, the baseline moisture content of the wood would be 7.5%. My builder and flooring contractor asked for me to give the hardwoods a season to acclimate and they would surely move back together in june/july time frame. Fresh cut trees can have a wood moisture content over 200%, while completely dried wood will have a wood moisture content of 0%. It will continue to absorb and release moisture until it comes into balance with the surrounding air. Ideally, it should be between 7% and 9%. Make sure theyre aligned with the grain and not across it. z .XWb*QGF^v4MQ`_dRw{\;\'03Uhx-SeJlc!m\8X^,Z/hU5Ewdzz:`nZ!(7reWD4X. If the water leak was bad enough, dry rot can occur causing possible structural integrity issues. Please provide us with regular updates. Moisture was around 25% when milled, and the ends were sealed. Do you see any dangers of using poly with a MC of around 12, or am I risking adhesion failure especially if the wood does end up shrinking dimensionally? Since wood is hygroscopic, it loses or gains moisture depending on the relative humidity of the surrounding air. Im looking for the % number that will be my upper boundary for oil application Would 12% be ok? Thank You. Any time water can be absorbed into a material such as wood, drywall etc, its always a good idea to check for excessive moisture, especially if you suspect a leak. When wood is subjected to an environment that is higher in humidity, it will swell or expand. in other hardwood areas that wasnt close to the water, was measuring about 16-19%. Different joinery (currently using pocket holes)? There will most likely be some shrinkage, so if possible, choose the clearest boards possible to lessen the possibility of any major cracking. Drying equipment removed 3 days ago. Hello Brian, I am a moisture meter expert, not a woodworking expert but from your description, the problem points to the conditions, not the wood or joinery. If youre wondering how wood can have a 200% moisture content, heres how that works. The joist span tables start with 26 lumber and it goes all the way up to 212. I recommend one of our Orion models: https://www.wagnermeters.com/moisture-meters/. There was a board that cracked along a glue line. Currently reading a 12.5%. The rim joist and floor joist sit right on the block. Why and how can I say this? Use a wet/dry shop vacuum, sump pump, or rags to clean up standing water or excess moisture from the floor and from the surface of the wood. hello I been getting very sick in my home so I had my manger do a mold and moisture test which came back high level of moisture levels which a contractor wants to take the sub floor up and 2 to 4 inches of the wall but my apartment manger is not releasing to report and hes is saying the spore test didnt pick up any mold spore question is it safe for me and my family to be in the home with high level of moisture in the restroom which the floor have been really soft for over 9 months now as well as the kids bedroom where a pipe burst. They are in an unheated and currently very cold barn The moisture ranges from 11% -16% according to my meter. Because of the different materials involved, they will react differently to high heat, thus giving you an un-even plywood surface. Thank you. The door is NE facing and protected from direct Sun light and rain by a porch roof. within two percentage points of the EMC where the wood is going to be used. A contractor is measuring sill plates by driving 2 SS Screws into the wood about 1-1/2 or so inches. Floor joists are generally 6, 8, 10, or 12 inches in width, with 8 or 10 inches as the most common sizes. For joists where the rot infestation has been thoroughly dealt with: it is acceptable to leave the joist as it is. If the conditions are too wet, dehumidify, and if they are too dry, humidify. Wood is a hygroscopic material, meaning it picks up or loses moisture based on the ambient conditions. If the wood is covered by a material like MDF or other, do we take 2x the measurements? Because wood shrinks and warps as it dries, woodworkers want it to be pre-shrunk before they use it. We have had very bad cracking in sheetrock and floors. 17 and the flooring is at 6 to 7. Here is a link to our website for more information: https://www.wagnermeters.com/shop/orion-950-smart/. I had a redwood deck, and they replaced it with Douglas fir (without my approval, but thats another issue). It is important to have the same temperature and humidity during those 2 weeks that will be maintained after installation. Floors should be: level within a 3mm deviation per 1m for floors up to 6m across (measured at the furthest points across the full width of the floor) a maximum of 20mm out of level for floors over 6m across flat within a 5mm deviation, measured using a 2m straight edge with equal offsets. When questioned, he said because Room is under 200 sq feet it is not a problem. can be laid with falls and set downs. provide a good substrate for a wide range of wet area finishes. I suspect the screws may be skewing the measurements. There are areas where organic growth was very active to cause deep, black discolorization. We dont know if we still should be having a commercial drying process? The other was for a $100 retail gift card. So, is it really this wet or is our meter over-reading? Thank you so much for your time and expertise. Instead of addressing the plumbing and damaged wood, they installed a dehumidifier in 2015. Characteristic of this wood easy to absorb of water and have large open pore. That doesnt make much sense to me. Softwoods typically have higher moisture content than hardwoods. There is no balancing layer on the reverse of the panels which might obstrust breathing of the panel. endstream endobj 81 0 obj <>stream This is more likely to occur to occur in lower-grade boards, where knots and uneven grains are already present. Waterproof membrane . Will the reading be accurate? Both slab-on-ground and suspended concrete floors for wet areas: are deemed impervious when steel trowel finished or polished. Wood is hygroscopic. In fact, according to M. Steven Doggett, Ph.D. LEED AP, the founder of Built Environments, Inc., wood moisture content as high as 15% can cause corrosion of metal fasteners and at 16% may lead to fungal growth. What should be the approximate Highest MC to prevent wood problems to include finishes? They many times cite the need for further evaluations by what they call other so called experts. Here is a link to our moisture meters, thermo-hygrometer, and Smart Logger. When you do this, you not only ensure that the entire batch is okay on average, but youre also far likelier to catch boards that are statistical outliers and could cause problems. I found your website at just the right time. If your subfloor is a wood product, make sure the reading is less than 20% on the moisture meter. I think mine is +-3% Is it possible being near the door just means greater humidity and there isnt actually a leak? Download a free version of NZS 3602:2003. Just press the scanning plate against the woods surface, turn on the meter, and receive the reading. Once the summer cooling season ends, and the A/C is shut off, and the outside air cools, and the humidity drops significantly, the cool dry air now flowing beneath the home dries out the floor joists. I have an unusual question, if I was to sandwich recycled paper (similar to hardwood floor paper only heavier) between 2 layers of wood as a draft stop what should the moisture content be to avoid the paper absorbing any water and ending up with a mold issue thanks in advance for any info you can provide. Bird, who runs the School of Fine Woodworking outside Knoxville, Tennessee, says he knows wood shrinks seasonally but wants to minimize the shrinkage and expansion by drying the wood to a moisture content of about 8%. Moisture content of 11.5% for the oak is a little high for furniture grade hardwoods. The electrical current will then move from pin to pin and measure the resistance encountered. These tools will give you the confidence that you have done everything on your part to ensure the highest quality in the piece you have built. If possible, keep indoor humidity below 60 percent (ideally between 30 and 50 percent) relative humidity. After my inspection I wrote the following report: As per your request, I visited the subject residence today to evaluate mold or fungus growth on the floor joists. We appreciate you writing in, best of luck! I live in coastal South Carolina .we are definitely afraid of mold formation. The moisture content overall is almost always below 20%. The excess moisture source should be corrected immediately, and monitored until the WMC returns to the 12-16 range. We found the problem and the leak was resolve quickly! The floor (under carpet) had long-term water exposure supposedly from a shower in the adjacent bathroom (according to the plumber). My question for you is, now that it is stained, can I still get an accurate MC? 12.5% is gettin there but not quite to the 6-9% mentioned in the article. The new wood was brought in in bundles ~2 x 2 x 6 and left that way to acclimate for ~2 weeks. This week, I notice the next pier on the same beam is starting to push up, warping the floor. Would the screws skew the measurements? Thats why I think the wood is either not dried to 14%, or it has picked up too much humidity after drying. And it's important to keep in mind that a glued-up panel behaves basically as one wide piece of lumber. When it comes to the moisture content of plywood or dimensional lumber, an MC of 17% to 19% reduces the overall strength of plywood, and an MC of 20% or more reduces the strength of dimensional lumber (i.e., lumber cut to certain predefined sizes, such as 2x4s). My first question is how to determine the MC of eng wood flooring which composite of different species layer, face and different species to form plywood core. The EMC in the recommended temperature/humidity range coincides with the 6% to 9% range used by most flooring manufacturers during the manufacturing and shipping process. Based on common guidelines or recommendations, the acceptable moisture levels for wood are as follows: Keep in mind that a woods acceptable moisture level will depend primarily on how it will be finally used and the average RH where it will be finally used. Screwed 2x4s parallel into the joists as added support. Add 1 to this value and round up the answer to the next whole number: 7.40625 + 1 = 8.40625 9 floor joists. Writing all the way from Australia, Steven. I have Suar wood from Indonesia and want use to indoor furniture, how range the Moisture Content allowance for this wood. The general process for using pin-type moisture meters is as follows. Thanks in advance for your input! Ideally, you want to check the EMC in the area you will be working on your slab, along with the area it will live in. Joists that sit below end matched joints must be at least 35mm thick. Its more important to understand that the wood is kiln-dried down to a certain bell-shaped range of MCs. Keep indoor humidity low. The boards have dried nicely so far with minimal warpage or checking. Here is a link to a moisture meter I recommend: https://www.wagnermeters.com/shop/orion-910-deep/. Was told thats not done. In general, 12% moisture or above is too wet to install flooring. What is the acceptable moisture level for plywood? i used my dremel with a shaping bit about 1/8 in to cut vertical slits or vents about an inch deep and a couple of inches tall into the bottom 24 and have kept a commercial floor blower on the wood several hours a day for more than a week yet, the number is not going down. He, of course, said that type of product is insufficient. If the middle is wet, you may experience cracking/splitting if dried too fast. These include warping, cracking, buckling, diminished wood strength, corrosion of fasteners, and even fungal growth. Any advice would be appreciated. Colorado is cold and dry. I would like to load eucalyptus and pine wood logs to India . Divide that difference by the sum of the on-center spacing of the floor joists: 118.5" / 16" = 7.40625. Why and how can I say this? I checked it with my new moisture meter and had a reading of between 8-13.5%. A floor joist is a horizontal beam, usually made of wood, that is used to support and enclose the flooring above a foundation. Too dry and you get chipping out of the wood. My meter tells me anything above 12% is wet but I cannot find any source of leaking or signs of water. Whats an acceptable moisture level for a brick wall in a house? Any suggestions to this being possible to correct? This building was constructed around 1966 and this little space appears very dry, in spite of a recent leak from an nearby hot water tank. This will drastically speed up the drying process. They are currently nearing equilibrium (around 12 MC) and are stored within the house. Typically, allow about 3 weeks for hardwood to acclimate in the environment. Thank you for sharing such valuable information. The water wasnt properly dried and organic growth was discovered by previous owner. When determining the acceptable moisture levels in wood flooring before installation, the NWFA states that the flooring professional should establish a baseline for acclimation. Any thoughts as to what the issue was with the first install so we dont have the same issue again next year after we go through a new install? It causes decay of the wood structure. Hello, I am renovating my kitchen and installing hardwood floors. I really need to know as I am getting so many different opinions Thanks. However, this time I was planning to use oil based poly rather than the spar urethane to reduce the amount of yellowing. Hello Enjoyed the article. Readings can be elevated if there is a stud directly behind the sheetrock. The ideal moisture content for hardwoods is between 6% and about 9%, depending on the ambient conditions around the wood. Be on the lookout for flooring failures such as swelling, buckling, cupping, etc. The interior home conditions are, AC running at 68-70*F. Exterior wall condition 104*F as checked with an IR thermometer of East wall not in the sun. The engineered wood floor appears ok. Call JADE today for a crawlspace inspection and we can give you definitive answers to your crawl space problems! Dryer wood produces more resistance than wetter wood. Here is a link to a calculator and table: http://www.csgnetwork.com/emctablecalc.html. But the table will be inside? While playing around with my pinless meter and checking the interior East and west walls on hot days, I notice the moisture content being very high 60% mc to off scale. I live in Charlotte, NC. This app will tell you the percent moisture content that a given temperature and humidity will equilibrate to. 12% is good for softwoods, but again, it depends on the relative humidity and temperature where the finished product will be kept. Building Performance Series No. It is also possible high moisture has entered the container during the trip to Europe. During the summer months in the northeast region, wood subfloors and floor joists often measure 19. -XF% On truss/joist spacing of 16" (406mm) o/c or less, the industry standard for single- panel subflooring is nominal 5/8" (19/32", 15.1 mm) CD Exposure 1 Plywood subfloor panels ( CD Exposure 1) or 23/32" OSB Exposure 1 subfloor panels, 4' x 8' sheets. Were looking to replace the floor in an old (unheated) hay barn with treated tongue & Groove 26 flooring and need to know if the advertised 19% MC will be ok and not shrink too much. He asked if I could double-check the findings of another home inspection company that requested expert advice on some mold/fungus they found in the crawl space of the home. We found out that RH at the final location was under 20%. Add an answer. The manufacturer of the oil-based poly should have a specification on the maximum allowable moisture content of the wood. I would love to be able to give you the perfect answer but unfortunately, there isnt one. 15% is too high, at least for hardwoods. Its never constant. Unless something is so out of whack shimming in back of the sheetrock won't suffice it's OK here. Wood in buildings usually has a wood moisture content of 5% to 15%. During my visit, I crawled to the four main corners of the crawl space and probed the floor system with an electronic moisture meter during this traverse. 78 0 obj <>stream The other question is what should the moisture content be on treated lumber that will be for the framing of the deck? Having performed multiple (>500) soil moisture and density Sieve and Proctor, so I am well versed in moisture calculations (both add and subtract). It is also a good idea to use a moisture meter after the three weeks just to make sure. Notice that the EMC of the in-use location is the same as the MC: So, using this chart, we know that in an area of the country where the RH inside a home or office is anywhere from 26-32%, both the EMC of the in-use location and the wood moisture content kept in that location will be 6%. i dont understand how the bottom beam looks like swiss cheese from all the holes ive drilled and has had a commercial blower on it for days yet the number is still high despite there being no visible water to keep the wood wet. I dialed the 800 number for Wagner meters and all I got was two sales pitches for a Life alert type device. Thank you, In wood products manufacturing, 6-8% is pretty much the norm, at least in North America. Which Orion moisture meter model would you suggest for my application? The optimal humidity in a home is generally 35%-55% and anything under 20% is actually considered unhealthy, as it dries out the skin. The substructure may show decayed areas, ranging from small to very large, of rotten floor joist, sills, and . Also, there is a risk of mold. If the MC of plywood is above 20%, can it be redried in a kiln or would that harm the glue? We have had an abnormally wet spring and part of summer. Now would the pine be okay to use as a top cover piece to an radiator cover? For example, if the moisture content of the delivered wood is 12% and the optimal MC is 6%, then physical problems will occur during the acclimation process. Therefore, in order to avoid post-construction problems, a woodworker building a cabinet for this particular interior environment would need to dry his wood to a moisture content of 8- 9% beforehand and then keep it that dry during the construction process. hL The interior was 3/4 BW the tables dimensions were 40x 70 . Call 256-318-0982 or contact us today. Wagner has a free app called WoodH2O to help you determine the proper moisture levels based on consistent humidity and temperature. There is only so much moisture a piece of wood can give up, over time, before a failure occurs. Best of luck with your project.