acceptable moisture levels in floor joists

Colorado is cold and dry. The boards should be no wider than 6 inches and installed on a 45-degree angle. Doesnt sound like this has been a problem in the past. There will be statistical outliers on both the low and the high end and youll want to catch these by using a quality moisture meter. look forward to your comments. If there are quite small amounts of moisture in a wall of dense plaster or brick, then a meter will probably indicate over 20% or so and this will be in the 'red zone' or beeps and squeeks may happen. endstream endobj 80 0 obj <>stream 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. Hi Larry, We are a joinery company and we have a project here in UAE which is located in another part of the emirates and the humidity in that area is very high especially during summer because it is near the coastal area. The shipping time is approximately 45 day in a 40 container to the west coast . I dont know what type of floor you have, but if it gets wet enough, about 25% moisture content or higher, mold can grow. Mold starts to grow in the mid to high 20 percent moisture contents. I would also consider the environment where the table will live. I would think at least fixing your dehumidifier is a must. I believe you are asking for the percent moisture content (humidity) of South African woods. Top 5 Causes of Cracks in Brick Veneer Homes. Finally the question I have is I-used your Wood H2O app and the humidity here (outside) is 55% and the temperature is near 70 (inside)am I correct that 10% is what Is the acceptable moisture of the wood should be for furniture building? It was such a good read. I want to use it to build a table and will be moving it to the location where I will work on it shortly. Ideally Ill wait until reaching final drying but sometimes I need to use wood before that point. There is over three foot of block above grade around the entire house. Its more important to understand that the wood is kiln-dried down to a certain bell-shaped range of MCs. Did the Contractor mention anything about the structural strength of the joists? The water was there for at most 6 hours, then we vacuumed it all and started the process of drying. Be notified when an answer is posted. This is all very helpful information, thanks! I really need to know as I am getting so many different opinions Thanks. This means your crawl space humidity goes up by about 22 degrees. 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. The process is time-consuming but produces accurate results if followed correctly. A termite repair company (also licensed contractors) told me that I needed to replace the planks on my second story deck. 800-634-9961, or email sales@wagnermeters.com. There are water stains on the particle board floor, but the flooring felt completely dry a few minutes after the reading was taken (I didnt see the reading being taken), the floor looks dry in the plumbers photo, the particle board flooring is not noticeably swollen, and it certainly has no flaking or other signs of disintegration or lessening to its structural integrity. One sheet of plywood is 25% next to a 2X4 truss reading 17-27%. I appreciate you sharing this important information with us at this time. To avoid this problem, wood flooring should never be stored where environmental conditions are uncontrolled, such as garages and exterior patios. Condensation present on the . Waterproof membrane . Are the measurements of all wood the same? Structural flooring for laying direct to joists or battens is a minimum of 19mm thick. 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. If the middle is wet, you may experience cracking/splitting if dried too fast. All that needs to be done at this home is to close-up the foundation vents during every air conditioning season and make sure the ground cover vapor barrier is spread completely over the underlying ground surface. endstream endobj 79 0 obj <>stream Here is a link to a calculator and table: http://www.csgnetwork.com/emctablecalc.html. It is also a good idea to use a moisture meter after the three weeks just to make sure. Lets go over the basics of each, Oven dry testing is the oldest method for measuring the moisture content of wood. Your email address will not be published. Cut in the spring and stacked and dried them over the summer. 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? Floor joists support most of your home's weight and play a crucial role in structural integrity. I built the tables in west Texas, but their final home is in Colorado. Thanks for the question. I-joists are strong, lightweight, "I" shaped engineered wood structural members that meet demanding performance standards. Mold and fungus in the crawl space can definitely become a problem, but dont be fooled into thinking that a Borate spray HAS to be applied in EVERY situation. Does that seem normal. During the summer months, when outdoor humidity is high, the hot/humid air enters the crawl space through the foundation vents and condenses on cool objects. 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. Is this dry enough that Id be able to reinstall the trim over the particleboard? Keep monitoring it. The acceptable moisture levels in basement walls and floors will depend on many factors. 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). If your subfloor is a wood product, make sure the reading is less than 20% on the moisture meter. Hi, in MN where extreme temperatures are very hard on homes. I have Suar wood from Indonesia and want use to indoor furniture, how range the Moisture Content allowance for this wood. 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. Foundation Underpinning Repair: Unnecessary? During the summer months in the northeast region, wood subfloors and floor joists often measure 19. within two percentage points of the EMC where the wood is going to be used. ft., based on a standard AStM F-1869 (Calcium Chloride) test, or 80% rh, based on AStM F-2170. Writing all the way from Australia, Steven. They need to carry a moisture meter with them under houses and probe the floor joists to measure wood moisture content. Higher values could mean a wet or saturated material. 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%. My main concern here is that the flooring didnt have enough time to acclimate to the surrounding conditions. 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. Whats the Difference Between a Home Inspection and an Engineering Inspection? How long will it take to get to the ideal moisture reading and is it better to be stored in a garage or inside a house? Too dry and you get chipping out of the wood. Free Webinar The What, Why, and How of Wood Moisture Testing. -25% moisture content in a VENTED crawl space. The Building Code states that houses must be built so that a 50-year flood will not enter the building. Thank you. I have a couple questions. One note is that we did have some fungus growth in our crawlspace during the construction phase prior to the crawlspace being sealed and had the contractor come and spray and clean the floor joists and subflooring where applicable. Hi Larry, just finished a black Walnut dining room table back in November. If that is the case you need to remove the flooring and examine the subfloor. Moisture was around 25% when milled, and the ends were sealed. I really appreciate your treatise on this matter. I found your moisture levels column through a search for good wood for low humidity. As with any wood product, the environment where the finished product will Live will determine the correct moisture content. The floor (under carpet) had long-term water exposure supposedly from a shower in the adjacent bathroom (according to the plumber). moisture meter testing a floor joist In this image we measure a reading of 37% in this floor joist. What do you recommend? We really cant overstress the importance of taking plenty of moisture readings. Alternatively, you could set up a crawl space dehumidifier and draw the . Other signs of high moisture readings include surface mold, evidence of water flows in the crawl space, evidence of water stains or evaporation from foundation walls and columns, evidence of condensation on ducts and evidence of water drops impacting the soil under ducts. Once the wood samples weight stops changing, its weight is compared to what it was before the drying process began. of the average flooring moisture content that is being laid). Good luck. The plumbing was improperly installed with the wrong cement to fit the pipes and could have been leaking from anywhere between 5-29 years while absorbing into the ground. I live in Atascadero CA and had a coastal red oak tree cut down this past summer. 10 14% moisture content is too high. After you remove the old flooring, you'll need to ensure the subfloor is properly prepared before laying the new vinyl, hardwood or laminate flooring. The National Association of Home Builders Green Home Building Guidelines for solid strip flooring and wide-width flooring are as follows: summary Wood flooring installers typically want the moisture content of their wood to be between 6% to 9%. I have come across this and havent made the purchase from my friend because I am not sure about the warp or breaking it will come. Im not sure I can really answer this question. Not only did the aggressive notching doom this joist, it affected the structural integrity of the floor system above. The three main sources of moisture: Condensation, Foundation wall transfer, and leaks. Which Orion moisture meter model would you suggest for my application? I get some water seepage through an exterior wall at basement floor level as a result of heavy rain. Timber logs & Lumber into India company remained actively involved in harvesting and sale of Hardwood logs of Indian origin. We had boards that were also cracking/splitting and other places where small pinholes were showing up. My plan is to make a wall-mounted headboard out of angle iron and these boards (boards will not be joined). It causes decay of the wood structure. At this home, cool objects include the air conditioning ductwork, the ground and the overlying wood floor system, which is exposed to very cool temperatures due to air conditioning duct leakage. A high reading in one area indicates a problem that must be corrected. Thanks. If this is confusing, dont worry. Most of it will dissipate. Hello I moved into my new home in June of 2018. What are acceptable ranges of moisture for composite materials like MDF and Plywood, for indoor furniture use? My thought is maybe to get one of your meter for greater accuracy? Wonder if they are trying to cover themselves. Wood Moisture Content is the weight of water in a piece of wood expressed as a percentage of oven dry weight of wood. Hello, Paul here. Readings can be elevated if there is a stud directly behind the sheetrock. info@rlcengineering.com The next sheet is 21.5% adjacent to 2X4. can be laid with falls and set downs. I am based in The Netherlands. Moisture levels in your crawl space that go beyond 70% lead to mold growth and health concerns. A 212 joist of the same species and quality can span nearly 25'. Should I wait for the slabs to be within that 6-9% to cut and glue? If the MC of plywood is above 20%, can it be redried in a kiln or would that harm the glue? Is it possible to get a 99.9% moisture reading (using a Cassain GM-200 hydrometer) on a particle board floor which looks and feels completely dry? Floor joists transfer loads to the vertical beams of the house. The thickness of flooring joists themselves will be determined by what's going on top of them. The fir windows and exterior doors will be affected by the the exterior and interior RH. I am not sure if this is pressure treated wood given its an exterior wall and if that affects what these numbers are. However, this range will vary slightly according to the geographic region because of varying RH levels. Cheers, Howard Pruden in Edmonton, Alberta where its cold and dry. For a wooden subfloor you will need to use a 2-pronged moisture meter. The front of the . Can I a cut them first, then glue them once they are dryer? These include warping, cracking, buckling, diminished wood strength, corrosion of fasteners, and even fungal growth. I used my Wagner meter and it Measured in the 10% area. Many of our customers are successfully using our hand held moisture meters on engineered flooring. Whats an acceptable moisture level for a brick wall in a house? My question: what is the complete saturation reading of wood? The normal outside equilibration moisture content (EMC) for Indiana is anywhere from 13% to 16%. This is based on a chart in Wood Handbook: Wood as an Engineering Material. Hug the ones you love when you see them! This app will tell you the percent moisture content that a given temperature and humidity will equilibrate to. The wood and varnish appear otherwise pristine, uncracked and not bubbled or clouded in any way. Why and how can I say this? 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. 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. Kiln-dried wood usually shows a moisture reading of 10% on the outside and then 25% on the inside. Best of luck with your project. Good moisture content for softwoods is 10% to 14% moisture. 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. Very educational! Add 1 to this value and round up the answer to the next whole number: 7.40625 + 1 = 8.40625 9 floor joists. 20% 28% Readings in this range indicate that conditions are border-line for decay. The floors have started cupping across the entire area with more in some parts. or finally the product will be placed where. this is an interesting read I landed upon as I was searching for MC in wood items. This method uses the oven-dry method and then compares the results to those obtained using a moisture meter. Call 256-318-0982 or, Engineering Inspection Mortgage Companies, Unnecessary Panic! In general, all wood products will swell with an increase in moisture content and shrink with a decrease in moisture content. This can be a problem once installed in furniture or a floor. Obviously, the ambient conditions within which the wood or paper is present can alter the MC% of the wood or paper. Thank You. Hello and thanks for writing in. Any advice would be appreciated. Oiling the surface does not control the moisture in the wood. Every home's foundation repair needs are different based on soil type, type of foundation problem, and climate. Crawl Space Inspections: Once a Year Keeps the Contractors Away! The subfloor registered from 12% to 17% . It is a 2-3 feet wide wet area that drains to a line connected to the city system. The size of the lumber used for floor joists is the single greatest determining factor in terms of how far a joist can span. Hardwood flooring needs to acclimate at least 2 weeks, in service conditions, before it is installed. Box 1437 What % does it have to get down to before it would be usable to make a table top ? with the spring thaw, i was one of the lucky ones that got water in my basement. The wood has been kiln dried and packed in corrugate. It is not fair to ask the seller of this home to pay some pest control firm to spray Borate on the floor system. I checked it with my new moisture meter and had a reading of between 8-13.5%. summary Acceptable wood moisture readings on a meter normally range from 6% to 8% for woodworking. They are currently nearing equilibrium (around 12 MC) and are stored within the house. Since water conducts electricity and wood doesnt, the dryness of the wood can be determined by the amount of resistance to an electrical current. Thanks for the question. After reading your article and following comments, my question is : How much does the finish of a wood project for indoor use affect the moisture content? summary Wood must always be allowed to acclimate or come into balance with the RH of the end-use location. Down pour of rain onto underlayment of attached garage. Hi Larry, So a friend of mine has some pine and oak blabs at MC levels of (oak 11.5%) and Pine 13-14%. The problem is some of the water made its way under the basmenet bathroom floor which is dricor with electric heating wire on top, then tiles, and unfortunately it looks like some of the dricor wood got wet as well! Thats why I think the wood is either not dried to 14%, or it has picked up too much humidity after drying. How to test moisture /water content in cassia bark? I dont know what to believe except the company who installed the vapor and dehumidifier said the vapor barrier needs to be changed out because of all the sewage and drainage stains after the plumbing is fixed. Thank you. They are now saying that they will replace whatever boards are bad and resand and finish the floors, however Im concerned that there is an underlying issue that will resurface here? Indoor humidity is around 50%, indoor temps around 70 degrees. Softwoods, such as spruce, can have more moisture. You can check for moisture by using a moisture meter. Once wood is dried below about 28% WMC, water is not available to support decay, unless the wood is exposed to liquid water. The plywood setting is .57. Currently the RH is 76%, the residence RH will be set at around 35%. Why and how can I say this? The supplier says they dry the wood to an MC of 14%, which is according to them the standard for outdoor furniture. Step 1: Check the Floor. Subfloor material such as plywood or OSB should measure between 10 and 14% moisture content. It is best to allow the wood to equilibrate to the room environment. Should you check moisture levels on a trailor floor on a massive rainy day? This would depend on the expectations of the person receiving the product in India, how large of diameter the logs are, and some average estimate of what the conditions would be inside the container during the 55 days. 10? My question is microwaving twice turned bowls what would be the general rule of thumb for a target by weight. Best, Kyle. When the wood neither gains nor loses moisture, we say that the wood has reached its equilibrium moisture content (EMC). primer, the moisture vapor transmissions rate (MVtr) from the substrate should not be in excess of 5 lbs. On a hot, humid summer day, the air venting into the crawl space could be as much as 75% relative humidity and 85 degrees. The joists can be longer or shorter as required by space and size, and are typically spaced at either 450mm or 600mm apart. And it's important to keep in mind that a glued-up panel behaves basically as one wide piece of lumber. These are slabs roughly 2 thick. Add an answer. Screwed 2x4s parallel into the joists as added support. Percent moisture content in wood is the ratio of the weight of water compared to the overall weight of a piece of wood. Below a 17% MC of wood, virtually no microbial growth will occur on even the most susceptible materials. Can carpet be reinstalled? I would like to load eucalyptus and pine wood logs to India . We are checking moisture levels in several areas each day. The acceptable wood moisture content normally ranges from 6% to 8% for woodworkers who build cabinets, fine furniture, musical instruments, dishes, toys, decorative art, boat restoration, or various other wood products. Thank you for sharing such valuable information. 12.5% is gettin there but not quite to the 6-9% mentioned in the article. If the leaks have damaged the sub floor or joists, call a licensed general contractor for repair. Replaced the subfloor, which is . For instance, the subfloor may appear to be dry on the surface, but still have elevated moisture within the panels. Accuaracy is of course more important.. It depends on the size of the project, but anytime you put a waterborne urethane on the wood you are adding moisture to your project. I hope that helps. From a strictly static MC%, 16-20% MC for long duration is going to promote mold growth. So, to sum up, Moisture in crawlspaces is bad. It is not uncommon for wood to expand or contract as much as a 1/8 per foot of width, so maintaining a stable environment is important. Perhaps better drainage around your house will do the trick or treat. Mold starts growing if the moisture contents reaches about 25% moisture content. Different joinery (currently using pocket holes)? of water/day/1000 sq. Pinless meters are non-penetrating and read the moisture content via a non-damaging electromagnetic sensor that scans the wood. This week, I notice the next pier on the same beam is starting to push up, warping the floor. We are shipping some acacia chopping board to colorado ( US) with moisture ranges from 10-14% while shipping from India but once product received all get cracked . for a mere $4900. Damn those shop classes I didnt take. 1. in Indonesia there are a lot of raw materials consisting of natural fibers, such as: pandanus, water hyacinth, rattan etc. 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. P.O. Im in Milwaukee, wi if that matters. Larry: I recently had my annual termite inspection. According to Dr. Eugene Wengert, professor and specialist in wood processing at the University of Wisconsin-Madisons Department of Forestry, wood should be dried to a water MC thats within two percentage points of the EMC where the wood is going to be used. And it really helps to pay an HVAC contractor to better seal and insulate the A/C ducts so they dont leak cold air!!! Here is a link to our website for more information: https://www.wagnermeters.com/shop/orion-950-smart/. Most types of wood species will mold above 25% moisture content, including pine. If the subfloor is not acceptable, it can often be overlaid with 1/2 -inch plywood. The National Wood Flooring Association (NWFA) has specific installation guidelines for wood flooring and how they relate to moisture content. Grain orientation matters . I was thinking 10% MC would be ok but after reading your article Im not sure. If a board reads 100% (Difficult to measure accurately) then the weight of the water equals the weight of that wood. Signs Of Moisture In Basement. A general rule of thumb for the coastal regions of FL would be 11-13%MC. 12% is good for softwoods, but again, it depends on the relative humidity and temperature where the finished product will be kept. Chris. There are two main types of wood moisture meters, pin-type and pinless. I installed a sump pump and 6 mil vapor barrier, but the barrier is not sealed around piers and the ground is moist under the barrier all year. We are manufacturer of eng wood flooring. While the surface of the floor might feel dry, there could be higher moisture inside. Do these levels seen appropriate considering the recent rainfall. Use a level to determine if the floor is level within 3/16-inch change per 10 feet. Make sure theyre aligned with the grain and not across it. These home inspectors are insecure and inexperienced. As a result, the normal moisture meter reading for these materials in between 0.5% and 1%. Please dont pay for a Borate spray unless the buyer wants to pay for it. In contrast, Las Vegas in the drier Southwest has much lower EMC percentages than most other U.S. cities. The optimal humidity in a home is generally 35%-55% and anything under 20% is actually considered unhealthy, as it dries out the skin. Avoid unnecessary moisture exposure of all wood components by enclosing the frame against adverse weather as soon as feasible. In this case, what Built in # that I can use to measure flooring. Is your electrical outlet that is 3 inches above the floor inside the house? What would be the recommended MC for doors of my new building(under construction)? 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. I have 1 1/2 thick cherry boards that I had milled from a tree in my yard last fall. Thank you. We appreciate you writing in, best of luck! A dry reading will be 16% MC (Moisture Content) or below. 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 he is using a high-quality product from companies such as Delmhorst, they provide a slide hammer pin attachment, and they need to use insulated-shaft pins. The maximum subfloor moisture level for solid strip flooring or wide-width solid flooring is either 12% or 13%, depending on the manufacturer. hellow! I gladly obliged. You mentioned it was installed just 3 days after it was delivered. water leaked over the edge. Unless something is so out of whack shimming in back of the sheetrock won't suffice it's OK here. As a general guideline, an emission rate of 1.4 kg/100m (3 lbs/1000 ft) or less is considered acceptable for most floor coverings. 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. My house is 24 years old. The NWFA recommends testing wood subfloor moisture in at least 20 locations per 1,000 sq.