acceptable moisture levels in floor joists
Was told thats not done. Hello Enjoyed the article. Its hard to gauge anything off of a cheapo meter, but if and I mean if, we were to assume it was reading effectively, the numbers are too high. Thank you. Fix & Replace Damaged Floor Joists - How to Sister a Joist I checked it with my new moisture meter and had a reading of between 8-13.5%. You mentioned it was installed just 3 days after it was delivered. Great article! All Rights Reserved. Meanwhile, the reference scale can be used to provide qualitative moisture assessments in other building materials. %PDF-1.2 % What humidity content should cedar be at for proper gluing. I had engineered hard wood installed and it is curling at the joints. If any of these conditions occur, tell your installer right away. A Guide to Subfloors Used Under Wood Flooring Divide that difference by the sum of the on-center spacing of the floor joists: 118.5" / 16" = 7.40625. hL 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. You will also see that the healthy wood moisture levels of 10% - 16% occur when the relative humidity is between 55% and 80% at 70 degrees. They said if i wanted to spend the money, a humidifier would help keep the humidity inside the house more consistent throughout the year. So, to sum up, Moisture in crawlspaces is bad. Which Orion moisture meter model would you suggest for my application? What is an acceptable crawl space wood moisture content? If the water leak was bad enough, dry rot can occur causing possible structural integrity issues. Failure to do this will result in warping, cracking, and other problems after the construction of the wood product. 800-634-9961, or email sales@wagnermeters.com. i am baffled. I manufacture ice cream sticks and disposable wooden cutlery from European Baltic birch wood in India. Just across the threshold to a white oak floor installed in ~1914 and the MC is 15%->16%. I have a question, I have moisture in the crawl space, we insulated the crawl with closed cell, cannot get the osb subfloor below. A floor joist is a horizontal beam, usually made of wood, that is used to support and enclose the flooring above a foundation. My meter tells me anything above 12% is wet but I cannot find any source of leaking or signs of water. It seems to me the supplier is drying the Teak to 14% because that is what is needed in Indonesia. Timber logs & Lumber into India company remained actively involved in harvesting and sale of Hardwood logs of Indian origin. The water eventually came out a electric outlet located three inches off the floor. . It is also possible high moisture has entered the container during the trip to Europe. within two percentage points of the EMC where the wood is going to be used. Hello and thanks for writing in. That doesnt make much sense to me. ( 55 days transit by sea) What should be the moisture content while loading in Containers? Readings can be elevated if there is a stud directly behind the sheetrock. With a Wagner L606, I am getting MC readings 12%->15.5% . 2. 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. summary Acceptable wood moisture readings on a meter normally range from 6% to 8% for woodworking. Hope that helps. Keep monitoring it. at one spot, its 40%. The difference is the moisture meters measurement error. They need to carry a moisture meter with them under houses and probe the floor joists to measure wood moisture content. There are two main types of wood moisture meters, pin-type and pinless. As stated, fungal spores are beneath the home because they are in the air we breathe-the same air that gets circulated beneath the home. Thank you. Substructures with WMC in this range may show decay or rot in floor joist, sills, and subflooring. Wood is a hygroscopic material, meaning it picks up or loses moisture based on the ambient conditions. 2nd question, will lacquer on surface of flooring affect the reading. Any opinions. 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. info@rlcengineering.com A moisture content that is too high will also slow the cure of the SLu and can affect the subsequent floor finish. Installing Hardwood Flooring Over OSB: It's All About Managing Moisture Also, if the leak was bad enough, it will be necessary to have a contractor make sure the strength of the subfloor isnt compromised. Request Answer. Here is a link to our moisture meters, thermo-hygrometer, and Smart Logger. moisture meter testing a floor joist In this image we measure a reading of 37% in this floor joist. There will most likely be some shrinkage, so if possible, choose the clearest boards possible to lessen the possibility of any major cracking. The lumber was recently milled, although the tree had been cut months, years ago. For example, a 26 Southern Pine joist can span 12'. The National Wood Flooring Association (NWFA) has specific installation guidelines for wood flooring and how they relate to moisture content. this is an interesting read I landed upon as I was searching for MC in wood items. 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. 1. Your cost could be more or less, depending on the size of the floor area. Hug the ones you love when you see them! My house was built in 1927. Keep indoor humidity low. We just had a hydrometer installed in the crawlspace and it is reading 38% as of today. Remember that the meter assumes it is reading timber. You can Google moisture content of wood necessary to support fungal growth and see for yourself. . Because pinless meters scan the woods surface and cover a larger area than pin-type meters, they provide a more thorough picture of the woods moisture content. Thanks!!! Kiln-dried timber should be kept dry. Based on common guidelines or recommendations, the acceptable moisture levels for wood are as follows: Wood objects used indoors: 6-8% Wood flooring: 6-9% Construction: 9-14% Keep in mind that a wood's acceptable moisture level will depend primarily on how it will be finally used and the average RH where it will be finally used. 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. Hello Folks, I am new to wood turning and do not have a ready supply of dry/seasoned (my wood is green) wood. Since the cold weather has come on, the organic growth has gone dormant, but a contractor noticed joists with distinctive moisture content where there are definitive separations between dry and wet looking wood. The sink vanity is made from typical laminated particle board, and Ive been trying to dry it in place using a dehumidifier and sealing the area off. About 5/16 penetration into the wood measures 8% using pins only. Sorry that this is so long-winded and I thank you in advance if you are willing to address this question for me. Were so sorry for the inconvenience. I do not have a hygrometer or a moisture meter as I am a hobbyist. They are currently nearing equilibrium (around 12 MC) and are stored within the house. 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. A11 - Substrate Testing - Floor Covering Reference Manual Floor Joist Calculator Cracks in Concrete Slabs: Should I Be Concerned? 3. Mold starts to grow in the mid to high 20 percent moisture contents. What would be the recommended MC for doors of my new building(under construction)? The home inspectors working for fees today seem to have one primary motive in mind: to cover their liabilities. Thank You. Did the Contractor mention anything about the structural strength of the joists? Knowing were all the piers are, I can stand on top and feel a small hump in the floors. What You Should Know About Septic Systems, Interior Slab Foundation Settlement: Evaluations and Cost of Repair. Outdoor temp is 99*F. Is this normal? Such readings should alert the homeowner to look for a source of excess moisture. Sorry, that time of year. Thanks. I would love to be able to give you the perfect answer but unfortunately, there isnt one. 12% 16% Readings in this range are common to lumber during construction, air dried lumber and healthy residential substructures (beneath first floor in crawl spaces). Subfloor material such as plywood or OSB should measure between 10 and 14% moisture content. My question for you is, now that it is stained, can I still get an accurate MC? Should it be less? Both slab-on-ground and suspended concrete floors for wet areas: are deemed impervious when steel trowel finished or polished. Here current humidity is 76%. Actually floors account for 15% of building heat loss depending on construction. Retain this information with your records. That is still quite a wide range. This means the weight of the water exceeds the weight of the wood by itself. Mold starts growing if the moisture contents reaches about 25% moisture content. Floor joists support most of your home's weight and play a crucial role in structural integrity. Your ideal MC will also depend on the outdoor humidity levels. The excess moisture source must be immediately corrected, and the situation carefully monitored until the WMC returns to the 12-16 range. the concrete was completely dry, no standing water. Brick Veneer Homes: Are They Really Worth the Headache? Two questions I need a reliable, easy to use meter that can cover all species as I now have a portable mill and that can be used for treated. The other was for a $100 retail gift card. Floor joists are generally 6, 8, 10, or 12 inches in width, with 8 or 10 inches as the most common sizes. This is a perfectly normal moisture content and one that will not support fungal growth. Logs, siding, shiplap, and T&G must be kiln-dried to stop the wood from shrinking or pulling apart. The reading was sky high in the pan and up two tiles high on the wall. Example: 1.2mm Hickory wear layer 9mm thick plywood compose of 7 layers, 2 layers acacia, 4 layers of Eucalyptus\2 layers Acacia and one layer Poplar. What % does it have to get down to before it would be usable to make a table top ? Dryer wood produces more resistance than wetter wood. Building Performance Series No. The purpose of the vapor barrier is to keep moisture away from materials that expand and contract. Would you be able to say anything about the optimal MC range for this specific situation? A study by Imamura and Kiguchi (1999) showed that wood moisture content in excess of 20% can cause a 5% loss of nail shank diameter in four years and a projected 25% loss in 30 years. If you know such International or Amercan or any other standard please let me know. Lacquer will not make a reading difference as long as there are no metallic components in the lacquer itself. 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 would think it would vary depending on the contents. Are the measurements of all wood the same? The moisture content of freshly cut wood is typically somewhere between 40-200%. This week, I notice the next pier on the same beam is starting to push up, warping the floor. My plan is to make a wall-mounted headboard out of angle iron and these boards (boards will not be joined). Thank you. Characteristic of this wood easy to absorb of water and have large open pore. Studies have shown, however, that mold growth can occur on wood at moisture content levels above 15 to 18 percent, and corrosion of metal fasteners in treated wood can occur when moisture content exceeds 18 to 20 percent. RH where they were built is about 29-30%. The manufacturer of the oil-based poly should have a specification on the maximum allowable moisture content of the wood. For instance, the subfloor may appear to be dry on the surface, but still have elevated moisture within the panels. We have a free App called WoodH2O that will tell you the moisture content given certain temperature and humidity conditions. We are manufacturer of eng wood flooring. Box 1437 28% and above Readings in this range are often accompanied by decay damage. Am I possibly getting false positives? Its never constant. With the WoodH2O-app I could deduct the EMC for The Netherlands would be between 15 and 16. 12.5% is gettin there but not quite to the 6-9% mentioned in the article. . It is best to replace the particle board subfloor. Condensation present on the . Before installing carpet, you will need to dry the subfloor first. When wood is subjected to an environment that is higher in humidity, it will swell or expand. However, this range will vary slightly according to the geographic region because of varying RH levels. The general process for using pin-type moisture meters is as follows. This will stop the wet/dry cycle that exists every year, in every ventilated crawl space containing A/C ductwork in the SE United States, over their lifetime. endstream endobj 79 0 obj <>stream Wood shrinks or swells as its moisture content changes, but only when water is taken up or given off from the cell walls. If the middle is wet, you may experience cracking/splitting if dried too fast. I may have missed this already but I have a few quick questions. Condensation on the inside of a windowpane. 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? If decay or WMC readings over 28% are present, find and fix the sources of liquid water quickly. Hope this helps. But this wetness is only surficial. 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 have 1 1/2 thick cherry boards that I had milled from a tree in my yard last fall. 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. Should I add a vapor barrier to floor joists under crawl space - Quora Its always a good idea to check with the manufacturer of the finish also. Ideally, it should be between 7% and 9%. 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. During the summer months in the northeast region, wood subfloors and floor joists often measure 19. PDF Solid Wood Flooring Installation - Mullican Flooring The supplier says they dry the wood to an MC of 14%, which is according to them the standard for outdoor furniture. If a wooden sample has moisture content range of 2-6% only and if it has moisture content of 9 or 10% then what does this mean?? What do you recommend? This means your crawl space humidity goes up by about 22 degrees. Installers should also measure the moisture in wood subfloors and concrete slabs as they can also affect wood flooring. 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. Below 12% Readings in this range are common to kiln or oven dried woods and furniture grades of wood, and represent dry conditions. Perhaps better drainage around your house will do the trick or treat. Thank you so much for your time and expertise. I suspect the screws may be skewing the measurements. Mobeen, If a wooden sample gains moisture, then the sample will increase in size. If the moisture content of the product is well outside the range of optimal MC, the wood flooring should not be accepted because it will lead to shrinkage, bowing, cupping, and other physical problems. Moisture content in floor systems - Structural Inspections - InterNACHI Or perhaps I should advise them to buy Wagner meters, for better accuracy ;-). With a degree in Computer Systems, Larry is involved in both hardware and software development of wood moisture measurement solutions. As with the hardwood flooring, it is essential to check the OSB's moisture content using a moisture meter. My question is regarding finishing. The floor (under carpet) had long-term water exposure supposedly from a shower in the adjacent bathroom (according to the plumber). Obviously, the ambient conditions within which the wood or paper is present can alter the MC% of the wood or paper. 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%. The water was there for at most 6 hours, then we vacuumed it all and started the process of drying. We have industrial fans going 24/7 to try and dry out the room and also have a dehumidifier running, Ive had the heated floor running in hopes that it could help dry any of the wet wood directly below. 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. For joists where the rot infestation has been thoroughly dealt with: it is acceptable to leave the joist as it is. A dry reading will be 16% MC (Moisture Content) or below. Thank you. In your area, wood that has been in an environment to a duration of time would be between 6-11%. Standards and tolerances guide | Queensland Building and Construction 2. What Are Safe Moisture Levels for Hardwood Floors? - Delmhorst Good luck. If this is confusing, dont worry. Most are reading are between 13-15%. Thanks in advance for your input! PDF Subsurface Tolerances and Floor Flatness Requirements A Case for We dont know if we still have leaks? look forward to your comments. for a mere $4900. The normal moisture content of wood (or EMC) varies from 7%-19% depending on the RH in the air. 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. 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 . summary Wood must always be allowed to acclimate or come into balance with the RH of the end-use location. The fir stock was originally KDd to around 8% but has been covered and stored outside for over a year and currently MC is around 12%. A moisture content of less than 20% indicates that your joists and beams do not have the necessary moisture content for mold or fungus to survive. Kiln-dried wood usually shows a moisture reading of 10% on the outside and then 25% on the inside. Three years ago, the floor sank in a heavy traffic area and an engineer told me Masonite was used to shim and had compressed. Wood used indoors will eventually stabilize at 8-14% moisture content; outdoors at 12-18%. Accuaracy is of course more important.. Prior to the flooring installation, make sure your subfloor has not experienced leaks or other water damage. We are very arid where the tops were built so I figured the tables would be just fine knowing that it is arid where they were goingbut that doesnt seem to be the case. The thinner veneers wont have much bearing on the reading. The ideal moisture content will depend on the humidity indoors. Furniture grade wood is typically dried to a target of 6%-9%. When exposed to a constant RH, the moisture content of wood or lumber will come to equilibrium with its environment, resulting in an EMC for that species of a wood-based composite. 10? -XF% All houses now use perimeter foundation so outside contact temperature stays at about 55 F all year. What is an FHA Permanent Foundation for Manufactured Homes? endstream endobj 81 0 obj <>stream Treatment levels for timber and timber-based materials used under tiles in wet areas where the waterproofing membrane cannot easily be inspected or maintained should be: H1.2 for timber floor joists and wall framing around showers; H3 (CCA treated) for plywood. Many thanks for your advice, really appreciate it! It is best to obtain a wood moisture content that will match the environment. 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? I used my Wagner meter and it Measured in the 10% area. Should I wait for the slabs to be within that 6-9% to cut and glue? Let's repeat that again. Floor levels and clearances | BRANZ Weathertight Colorado is cold and dry. So, when looking at the relative humidity of the space, spaces left above 70% RH for extended periods will also promote mold growth. As with plywood subfloors, if there is movement or squeaks, refasten the subfloor to the joists and set protruding fasteners into the subfloor. Thank you for your very informative knowledge about all of the items on this page. Whats an acceptable moisture level for a brick wall in a house? Thanks for the question. What Are Acceptable Moisture Levels in Wood? - Wagner Meters They are in an unheated and currently very cold barn The moisture ranges from 11% -16% according to my meter. Hello, Paul here. A Homeowner's Guide to Floor Underlayments | Hunker The best way to do this is to use an accurate moisture meter. Where are you located? Truss Uplift: Who Would Have Ever Thunk It? Im planning on using some of it to build a new front door for the house and was wondering what MC I should be shooting for. I strongly recommend using a moisture meter, along with a thermo-hygrometer, or even a smart logger before you start building, to ensure the wood is at an optimal moisture content in an environment that has an acceptable relative humidity and temperature range. Floor Joist Sizing and Span In Residential Construction - Weekend Builds Production, storage, delivery and construction and in-use conditions that will prevent exposure to external or internal moisture or conditions that would allow the moisture content to exceed 18% at any time: Untreated Douglas fir: Framing in a low-risk building and meeting the requirements of B2/AS1 paragraph 3.2.2.2: Where there is a risk of . Down pour of rain onto underlayment of attached garage. These are the "safest" conditions for most types of woodbetween 60 and 80 degrees Fahrenheit and 30% to 50% RH. 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. meter readings of up to 2.0% and in-slab relative humidity (RH) below 75%. Continue reading MC in the home. Copyright - RLC Engineering, LLC. You can now understand the meaning of moisture content 5.5%, 15 g/m2/24 hours, and relative humidity 75% with these facts. Perhaps there is something different about the East and West walls. I am based in The Netherlands. 2-1/4", the moisture content between the flooring planks and the subfloor should not exceed 2%. The thickness of flooring joists themselves will be determined by what's going on top of them. It is also a good idea to use a moisture meter after the three weeks just to make sure. Additional care is necessary if laying parallel to the joists and sheet subfloors can sag between the joist. How to Level a Floor - Lowes If you need further clarification http://www.nwfa.org is an excellent source. Box 1088, Roseburg, OR 97470 Tel. Moisture In Crawl Space - How To Prevent and Fix The Problem ie SW=Starting weight, TW=Target weight, using T%=Target percentage My calculation ( T% X SW = TW). 2. Sometimes moving the air around is enough to remove moisture and dry surfaces. He wants to install his companys system, seal all external openings around connections, etc. The National Wood Flooring Association (NWFA) has a chart that indicates the moisture content of wood at any given combination of temperature and humidity. Most types of wood species will mold above 25% moisture content, including pine. Yes, the wood can still be read for MC with a stain on it. Does coating wood with oil stabilize the moisture content in wood? In contrast, Las Vegas in the drier Southwest has much lower EMC percentages than most other U.S. cities. They many times cite the need for further evaluations by what they call other so called experts. Both times, the tables were flawless, but after 2-3 weeks in their new home both table tops had major crack issues. Top 5 Causes of Cracks in Brick Veneer Homes. Since wood is hygroscopic, it loses or gains moisture depending on the relative humidity of the surrounding air. We also have an Orion 950 moisture meter that will automatically give you EMC (Equilibrium Moisture Content) and other useful statistics. Screwed 2x4s parallel into the joists as added support. Interior walls non-insulated at around 7-8% mc. The more specific way to know would be to measure the relative humidity and temperature in your homes air and then plug the numbers into a calculator like this https://www.spikevm.com/calculators/logging/equilibrium.php This will tell you what the MC% should be based on your specific environment. Houses with timber-framed floors can be at risk of having poor underfloor ventilation. This is all very helpful information, thanks! The crawl space must be a minimum of 18" to the bottom of the floor joists, and the soil in the crawl space covered with a heavy duty plastic moisture barrier, and sealed at the seams. And would it be normal for the MC to vary from board-to-board and one end of a board to the other? If the humidity is a constant 76% then the wood will equilibrate between 14 and 15% moisture content. 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. Surface molds may develop.