. 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. They are currently nearing equilibrium (around 12 MC) and are stored within the house. That is still quite a wide range. Two weeks is sufficient for softwood. In contrast, Las Vegas in the drier Southwest has much lower EMC percentages than most other U.S. cities. Learn how your comment data is processed. This summer I milled several 1.25 boards from a fir log that had been cut around 10 years ago. If this is confusing, dont worry. Very simple and understandable. I requested the treated lumber be brought in a few weeks prior to build, stickered and put under cover to acclimate and dry it. Should I remove more foam to be sure. The home inspectors working for fees today seem to have one primary motive in mind: to cover their liabilities. The home inspector failed to report all the sewage stains on the plastic and organic growth on some of the joists have which had been exposed to moisture the whole time even though the dehumidifier has been mitigating the plumbing leaks. There are areas where organic growth was very active to cause deep, black discolorization. It is possible, in some species, to have a moisture content higher than 100 percent. Ev ( 55 days transit by sea) What should be the moisture content while loading in Containers? 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. Sometimes moving the air around is enough to remove moisture and dry surfaces. Its more important to understand that the wood is kiln-dried down to a certain bell-shaped range of MCs. Standard moisture contents for hardwoods are 6% 9% MC. Many thanks for your advice, really appreciate it! Maximum Moisture Content Of Concrete This is a nominal value most product manufacturers specify when concrete is dry enough to allow their product to lay down on it. 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. Such readings should alert the homeowner to look for a source of excess moisture. As far as the oil finish, the manufacturer of the oil will specify the correct moisture content for an application. 2. Although, in this example, the moisture content of the timber rarely goes above 17%, it is not uncommon for winter moisture contents, in pitched roofs, to peak above 25%. This app will tell you the percent moisture content that a given temperature and humidity will equilibrate to. I had engineered hard wood installed and it is curling at the joints. Summers are hot and dry while winters can be cool. Characteristic of this wood easy to absorb of water and have large open pore. 25-30 - Actual, and often extensive, damage is evident when readings reach this level. It is impossible for me to tell you what the percentage of furniture should be, but if you know the EMC in the area it will be kept, you can check the MC continuously until you reach its EMC. Wide-spread and often extensive moisture damage occurs in residences across the state of South Carolina and elsewhere in the Southeast due to the regions warm, humid climate. Hello, I am renovating my kitchen and installing hardwood floors. However, and unless otherwise permitted by a flooring product manufacturer, the following maximum moisture emission levels over a 24 hour period are permissible for the following floor coverings types: Reaching these moisture content levels does not mean mold growth or corrosion . This only occurs when wood changes moisture content below the fibre saturation point. Would the screws skew the measurements? We are checking moisture levels in several areas each day. If the water leak was bad enough, dry rot can occur causing possible structural integrity issues. However, the ideal humidity range in some climates may be higher or lower. Subfloor material such as plywood or OSB should measure between 10 and 14% moisture content. We dont know if we still should be having a commercial drying process? A termite repair company (also licensed contractors) told me that I needed to replace the planks on my second story deck. If the humidity is a constant 76% then the wood will equilibrate between 14 and 15% moisture content. What are Acceptable Moisture Levels in Wood? Thanks. Now would the pine be okay to use as a top cover piece to an radiator cover? A dehumidifier in the crawlspace will help but can be expensive. This is the standard in the construction industry. Also, the glue manufacturer should ideally give you some specifications for max and min moisture content. Floors-1/2" in 12' or 3/16" in 4'. Typical moisture content for furniture in a home is 6-9%. Here is a link to our new line of meters: https://www.wagnermeters.com/moisture-meters/. This is for furniture-grade hardwoods. How Timber Reacts To Moisture. Did the Contractor mention anything about the structural strength of the joists? You are correct, furniture grade hardwood is typically dried between 6 to 9%. I am not familiar with the particular moisture meter the plumber was using, but assuming it is correct, that moisture content is way too high to install new flooring. Surface molds may develop. Seattles EMC ranges from 12.2% to 16.5%. I had it milled into 2.25 slabs and I stacked it on a deck area. Wood is a hygroscopic material, meaning it picks up or loses moisture based on the ambient conditions. Typically, allow about 3 weeks for hardwood to acclimate in the environment. Be notified when an answer is posted. Wall Corners-Perpendicular within 1/4" in 10'. Its mc is 11- 12% . 12.5% is gettin there but not quite to the 6-9% mentioned in the article. Like all wood materials, I-joists are susceptible to moisture. They many times cite the need for further evaluations by what they call other so called experts. Substructures with WMC in this range may show decay or rot in floor joist, sills, and subflooring. 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. Will your meters work to find MC levels for composites? Please dont pay for a Borate spray unless the buyer wants to pay for it. These WMC readings are usually provided by pest control operators, and are included in the termite letter (form CL-100 Official South Carolina Wood Infestation Report). This author has found decay fungi in floor joists at moisture levels of 20% to 25%. The maximum subfloor moisture level for solid strip flooring or wide-width solid flooring is either 12% or 13%, depending on the manufacturer. What is the acceptable water/moisture content in cassia bark?- in south east asia. Not using the correct procedure. I have one question with regards to pinless moisture meters and wallboard/Sheetrock. Eventually, this internal moisture will evaporate by itself. And would it be normal for the MC to vary from board-to-board and one end of a board to the other? primer, the moisture vapor transmissions rate (MVtr) from the substrate should not be in excess of 5 lbs. 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. You can Google moisture content of wood necessary to support fungal growth and see for yourself. Both times, the tables were flawless, but after 2-3 weeks in their new home both table tops had major crack issues. 2-1/4", the moisture content between the flooring planks and the subfloor should not exceed 2%. The angle iron will prevent much warping, and I do plan on finishing all sides (and ends). Thanks!!! I checked it with my new moisture meter and had a reading of between 8-13.5%. Building Performance Series No. the curb is built with 3 2/4s stacked on each other. Everyone who works with wood needs to understand how wood interacts with moisture in the environment. So, is it really this wet or is our meter over-reading? Most types of wood species will mold above 25% moisture content, including pine. I have Suar wood from Indonesia and want use to indoor furniture, how range the Moisture Content allowance for this wood. Too wet and you get fuzzing. Larry Loffer is a senior technician at Wagner Meters, where he has over 30 years of experience in wood moisture measurement. Damn those shop classes I didnt take. 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. Effects of Moisture on I-Joists and LVL April 2007 P.O. I hope this helps. Hello, Paul here. A wood moisture content of 47% is too high. While the surface of the floor might feel dry, there could be higher moisture inside. Most are reading are between 13-15%. I would also consider the environment where the table will live. 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. Outdoor temp is 99*F. Is this normal? When it hits the cooler air of the crawl space, it increases the relative humidity by about 2% per degree! 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%. What do you recommend the reader to be at before insulation and drywall on new construction? We have a free app called WoodH2O for Android or iPhone. Were in northern Indiana, humid summers long cold winters. It constantly absorbs and releases vapour into the . Over a year ago, I re-shim all the piers with metal shims. Set the meter to the species that makes up the bulk, in this case, the plywood. You can use a dehumidifier when you need your crawl space drier, but it's essential to maintain proper moisture levels as much as possible. 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. Using wood with a moisture content above 14% isnt recommended because it may have detrimental long-term effects on the construction. /U (li7":-JOBHO,9UY) /P 65492 >> endobj 14 0 obj << /S /GoTo /D [ 15 0 R /Fit ] >> endobj 27 0 obj << /S 45 /T 91 /Filter /FlateDecode /Length 28 0 R >> stream Ceilings account for 35%, walls - 25% and windows 25%. Thank you. These varying humidity levels of the surrounding air cause wood to not only gain or lose water moisture but to expand or shrink as well. As the humidity decreases, the MC decreases, causing the wood to shrink. Most floor joists are single or double, and most often made with 2x6s or 2x8s. Well, tile, bricks, and stones are known to have a low water-holding capacity and therefore should be dry. Hello! Kiln-dried wood usually shows a moisture reading of 10% on the outside and then 25% on the inside. I would think at least fixing your dehumidifier is a must. What are acceptable ranges of moisture for composite materials like MDF and Plywood, for indoor furniture use? For a wooden subfloor you will need to use a 2-pronged moisture meter. I appreciate you sharing this important information with us at this time. These home inspectors are insecure and inexperienced. somewhere. Above 90% RH or 20% WMC, mold can grow on the wood. If you want, just give me a call at 800-634-9961, ext 225. This should be stuck into your wooden subfloor. In March of this year I had new white oak 2 flooring installed. The floor immediately felt stronger. Your ideal MC will also depend on the outdoor humidity levels. Utilize the chart on following page to record the environmental readings at the time of installation. These are the "safest" conditions for most types of woodbetween 60 and 80 degrees Fahrenheit and 30% to 50% RH. As a result, the normal moisture meter reading for these materials in between 0.5% and 1%. Most interior wood is in this range. If that is the case you need to remove the flooring and examine the subfloor. Mold starts to grow in the mid to high 20 percent moisture contents. 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. 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.
acceptable moisture levels in floor joists