acceptable moisture levels in floor joists

My meter tells me anything above 12% is wet but I cannot find any source of leaking or signs of water. We will be having a deck built off my woodshop. 2013-10-14 03:14:29. For joists where the rot infestation has been thoroughly dealt with: it is acceptable to leave the joist as it is. 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. "R. Kiln-dried wood usually shows a moisture reading of 10% on the outside and then 25% on the inside. 3.Vacuum and/or Wipe Excess Moisture. Here current humidity is 76%. In contrast, Las Vegas in the drier Southwest has much lower EMC percentages than most other U.S. cities. They delivered the wood one day, and began to stain and install it over the next two days, finishing on the 6th day. Before installing plywood underlayment, ensure that the existing flooring is thoroughly vacuumed, free from debris, and stripped of wax. I removed an of the foam insulation. This site uses Akismet to reduce spam. Just press the scanning plate against the woods surface, turn on the meter, and receive the reading. A 10% moisture content reading means that 10% of a wood samples weight is due to water in the wood. My plan is to make a wall-mounted headboard out of angle iron and these boards (boards will not be joined). could you please guide or on how much should be the Expected Humidity % in high Humid areas like UAE considering these are mostly for Indoor purpose where ACs are on 247 at say 24 Degrees. I found your website at just the right time. Any suggestions to this being possible to correct? A wood moisture content of 47% is too high. Question: Just to make sure that you get accurate moisture measurements, has your moisture meter been checked for calibration? Typically, allow about 3 weeks for hardwood to acclimate in the environment. Wood shrinks or swells as its moisture content changes, but only when water is taken up or given off from the cell walls. Simple and regular maintenance can prevent serious problems developing. The National Wood Flooring Association (NWFA) has specific installation guidelines for wood flooring and how they relate to moisture content. You should be able to specify a lower moisture content. Thanks! Just across the threshold to a white oak floor installed in ~1914 and the MC is 15%->16%. SE, Huntsville, AL 35802. Have I been wrong? Prior to the flooring installation, make sure your subfloor has not experienced leaks or other water damage. Im trying to find specs on treated lumber for NC. Brick Veneer Homes: Are They Really Worth the Headache? Engineering & Inspection Services, Licensed PE - Alabama & Tennessee, JADE Engineering & Inspection | 5405 Whitesburg Dr. thanks so much in advance. This is a perfectly normal moisture content and one that will not support fungal growth. If you need further clarification http://www.nwfa.org is an excellent source. I have been testing the bottom stud/sill board of an exterior wall on a slab of an old house that exposed in order to put a floor in. I have a black walnut slabbed up that has been air drying outside for 2 yrs. 1. Also, there is a risk of mold. Your help for resolving this issue would be highly appreciated . We also ship to other European countries, for dryer country like Spain the EMC could be between 12 and 14. It is best to obtain a wood moisture content that will match the environment. Looking back at pictures of the build process, they brought the hardwood bundles into my home in late October of 2017 and installed them 3 days later. Am I possibly getting false positives? If the moisture is less than 20% and the floor joists are structurally sound, like the joists at this home, there is no need to worry about any fungal staining that might exist. It is a 2-3 feet wide wet area that drains to a line connected to the city system. Or perhaps I should advise them to buy Wagner meters, for better accuracy ;-). But when you touch the pins to the embedded screws, you get between 14 and 24 % in various areas of the board. Signs Of Moisture In Basement. Foundation Underpinning Repair: Unnecessary? A termite repair company (also licensed contractors) told me that I needed to replace the planks on my second story deck. There are two main types of wood moisture meters, pin-type and pinless. The wood has been kiln dried and packed in corrugate. 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. Such readings should alert the homeowner to look for a source of excess moisture. It is possible, in some species, to have a moisture content higher than 100 percent. You are correct, furniture grade hardwood is typically dried between 6 to 9%. To the right, 13.2% in the same distance and also drops to ~ 8% after. %PDF-1.5 % Cut out a portion (approx 1/2" I think) from the top of the floor joists. Wood Rot in Crawl Spaces: Whats That Smell in My House. The joist span tables start with 26 lumber and it goes all the way up to 212. The pins are pressed into the wood to obtain a reading. Softwoods typically have higher moisture content than hardwoods. I hope that helps. I was able to get the MC down to 15%. Ive been following your in depth blog on moisture meters for around 1 year now. Should I remove more foam to be sure. For example, from 25% to 45% or from 45% to 65%. 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These are typical readings for exterior wood. Wood is a hygroscopic material that contains water, even after it is cut from a tree. 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. My question is regarding finishing. The company they hired measured 47% in the wood and declares that this must be ripped out and replaced. ie SW=Starting weight, TW=Target weight, using T%=Target percentage My calculation ( T% X SW = TW). It is also a good idea to use a moisture meter after the three weeks just to make sure. in other hardwood areas that wasnt close to the water, was measuring about 16-19%. The photo shows a floor that is out of level over four or so boards adjacent to the external wall. Building Performance Series No. at one spot, its 40%. The builder's warranty representative came out and measured the moisture levels with a moisture meter. Hi, we live in a coastal area, had a recent water leak, and a hard wood floor MC is measuring about 25% the water did not contact this area directly. Percent moisture content in wood is the ratio of the weight of water compared to the overall weight of a piece of wood. We also have an Orion 950 moisture meter that will automatically give you EMC (Equilibrium Moisture Content) and other useful statistics. Once the wood samples weight stops changing, its weight is compared to what it was before the drying process began. The cedar I have is now at 12-16%. What is the acceptable moisture level for plywood? I would love to be able to give you the perfect answer but unfortunately, there isnt one. How Timber Reacts To Moisture. 0 WM=8DBaHh10tIKR/OH}X5Kpt'_]4Mfg9@w8~ n$R Heres how it works. The reading was sky high in the pan and up two tiles high on the wall. Wood is used to clean model railroad tracks. If the subfloor is not acceptable, it can often be overlaid with 1/2 -inch plywood. I dont know what type of floor you have, but if it gets wet enough, about 25% moisture content or higher, mold can grow. Structural flooring for laying direct to joists or battens is a minimum of 19mm thick. I took readings of the moisture of the sub floor at the edges of the wall and it ranged from 5 to 16, problem is i cant take it in the middle of the floor unless i rip the floor out. Are the measurements of all wood the same? )IS0i 1P *V? U? moisture will typically measure 7-10%. You can determine the correct percent moisture content by using our free app called WoodH2O. Here is a good source for mold and wood: 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..206760.0..0.100.1475.25j10.1..gws-wiz..0..0j0i131.PkfEQYRef9I. The Building Code states that houses must be built so that a 50-year flood will not enter the building. In your blog I read that furniture for outdoor is dried to a MC between 9 and 14%. Im on a grade-level concrete slab, and the water made its way over (under the tiles) to my sink vanity. 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. 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! I had a pin meter but found I had to put the pins in the ends or try to find an area that wouldnt be seen, so Im thinking a pinless might be better. However, many building materials may have been dried down to about 15% moisture content. An MC in this range, therefore, is considered sufficiently dry for exterior in-service wood. I would not recommend re-drying finished plywood. The solution seems to be drying the wood longer & bettter, to a lower measured MC. About 5/16 penetration into the wood measures 8% using pins only. And it really helps to pay an HVAC contractor to better seal and insulate the A/C ducts so they dont leak cold air!!! we had a problem with our shower curb. Repair is often required when WMC readings are in this range. Im down to ~13-19% MC near floor level, based on a cheapo moisture meters readings. 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. They many times cite the need for further evaluations by what they call other so called experts. my question is, is there a possibility that the wood will shrink because of the weather condition?the wood that we used for the door frames and bidding is beechwood. 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. Interior walls non-insulated at around 7-8% mc. 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. Other than causing structural damage, too much water can result in mold growth. Hello! wood using pins while the MDF uses pinless? If the MC of plywood is above 20%, can it be redried in a kiln or would that harm the glue? 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? The SG setting is on the card that comes with the meter. Kiln-dried timber should be kept dry. Why Do So Many Homes Have Cracks in Their Brick Veneer? I have a question. we are getting hardwoods from our Uk Suppliers and accoya coming in at 2% and once we use the timber we are reading 0% we have tested the reader and its accurate even joinery grade sapele wood and Tulip wood coming in at 0% we cover these in 3 coats of sikkens paint and sometimes we get jobs where we are having to go back as our joinery is moving and we are guessing its because of these moisture levels and had never checked previously. Limit the length of notches to 1/3 of the joist's depth. The substructure may show decayed areas, ranging from small to very large, of rotten floor joist, sills, and . I am building a farm style dining table with pecan 2 thick X 8-0 long boards. Floor joists support most of your home's weight and play a crucial role in structural integrity. Accuaracy is of course more important.. In their warehouse, and perhaps partly also in the container. Thank you for the well described article. This summer I milled several 1.25 boards from a fir log that had been cut around 10 years ago. 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. I want to use it to build a table and will be moving it to the location where I will work on it shortly. The manufacturer of the oil-based poly should have a specification on the maximum allowable moisture content of the wood. 2. Hi Larry, just finished a black Walnut dining room table back in November. Would the screws skew the measurements? I suspect the screws may be skewing the measurements. There are areas where organic growth was very active to cause deep, black discolorization. Room size, L-shaped, is 21.5 x 12.5 and leg of L is 8.5 x 11.