Common questions related to bamboo floor installation
Glue down. While this is the most expensive and labor-intensive method, it is also considered the most stable method as the glue provides sound and moisture insulation, and the elasticity in the glue allows the floor to expand and contract naturally with the seasons. Our floors can be glued down to a multitude of surfaces. Be sure to check out the Acceptable Subfloor Types table in our installation instructions. If you're gluing down over plywood you can use a basic bamboo flooring glue, but if you're going over a slab you'll want to choose an all-in-one glue for bamboo flooring over concrete. Remember that it's important to use the correct trowel in tandem with the glue you've chosen. If you use the wrong trowel you may not get the correct spread rate, causing your floor to fail. This can be a very expensive mistake!
Floating. The advantage to a click-lock floating floor is the ease of installation as it is less time consuming to install. It is also easier to repair floating floors should you ever have a leak or other problem. The disadvantage is that, unless your home has stable indoor humidity year-around (meaning it stays within a 30% range the whole year), you are limited in the length of the continuous runs of flooring you can lay. Across the widths of the planks (tangentially) you are limited to 25 feet with engineered floating floors and 15 feet with solid floating floors. Running down the lengths of the planks (longitudinally) you are limited to 45 feet with engineered floating floors and 25 feet with solid floating floors. For this type of installation we recommend you use a 3 in 1 underlayment.
Both click-lock and tongue and groove floors can be floated however tongue and groove floors are time-consuming because you have to apply a bead of glue along the entire length of the inside bottom groove of every plank. As mentioned in the paragraph above, unless you have very stable/constant interior humidity settings year-round you'll also need to be very careful to mind the recommended maximum run lengths.
For moldings installation you may need to use a Bostich Porter 23 gage micro nailer or similar gun.
For all guns, make sure cleats and nails are set properly before continuing to the next row, failure to do so may result in goosebumps/dimpling. You may need to try several pressure/PSI settings before finding a setting that will work – test on sacrificial planks. Ensure the connector hose, seal and air compressor are fully functional and have no tears or defects.
If you do not use the correct nail gun or cleat size, you may get dimpling in your floors. Read this important document about goosebumps and dimpling in strand woven bamboo.
Do not acclimate the floors on top of concrete, carpet with concrete under it, crawl spaces or any other sub-floor that may contain moisture, without first laying a 6mm polyethelyne plastic barrier down, or the flooring will soak up the moisture from the concrete and shrink post-installation. Make sure to extend the apron/border of the plastic barrer at least 18 inches beyond the flooring boxes.
First, stack the boxes up to 5 high, with each stack located at least 3 feet away from the next. Cross-stacking is preferable if you have the space. Once the boxes are stacked, use a box cutter or sharp knife to cut each box down one entire side lengthwise, and also the end flaps. Make sure to also cut open the interior plastic so that the floors really breathe.
Ensure that the flooring is acclimated in an environment (temperature + humidity) that will closely match the environment in which the floor will used in. Remember that you must keep your interior humidity settings between 40%-60% (as for all wood floors) or you may experience increased expansion and contraction.
1) If you're gluing the floor down to plywood or any other approved substrate, you'll want to use a zero VOC 100% urethane trowel-down adhesive approved for wood flooring installation. When installing over plywood you don’t need glue that contains a moisture barrier unless there is a crawl space or other moist environment under your sub-floor. If there is a crawl space, make sure to follow our installation instructions which provide a complete set of floor prep guidelines.
2) If you're gluing the floor down to concrete or any other sub-floor that may be emitting moisture, most of these cases will require an adhesive that contains a moisture barrier. These adhesives are slightly more expensive than basic adhesives but well-worth the investment. We sell a great zero VOC adhesive with moisture barrier that works not only for bamboo but for all types of wood floors and even some tile, and it comes with the bonus of also having a sound barrier, so many of our clients use it on their upstairs floors to keep noise levels down. Important: always make sure to use the the correct trowel style and size for the type of adhesive you select or you may not get enough coverage on the floor and this will cause the installation to fail.
About Moisture In Concrete. Most concrete slabs emit moisture for up to 25 years after being poured, and installing a floor over such a slab is easy to do, however as with any other job done right you want to make sure you have the right tools, and adhesive, on hand. Moisture is measured in pounds on concrete slabs. Basic adhesives usually protect up to about 3 pounds of moisture. Meaning, if you test the concrete and it comes back higher than 3, you need an adhesive that contains a moisture barrier.
Keep in mind that moisture tests only test the moisture on any given day. A slab may read 8 lbs per square foot one day but then it rains for a week and the moisture rating jumps to 14. Our glue with moisture barrier mentioned above protects your floor up to 15 pounds of moisture per square foot which is very high and usually more than enough for all jobs. There are also unlimited vapor barrier glues on the market but they are very expensive and typically only used for "wet" slabs.
As to the direction of the flooring planks in relation to the joists below the sub-floor, this depends on several factors mostly related to the current condition of the sub-floor. If the subfloor is observed to be sagging, it is recommended that you install the planks in a perpendicular direction compared to the joists. This is a call you'll want your installer to make as he/she will need to inspect the sub-floor prior to installation.
Important Note About Crawl Spaces: Many wood floors fail due to the failure of the installer to address moisture in crawl spaces. If you have a crawl space under your home or new flooring, you must properly remedy this moisture.
You must have a high quality vapor barrier or moisture insulation (with 100% blockage) or the moisture coming up from the crawl space will damage the flooring. A ground layer cover is required - must be 6mm minimum black polyethylene with joints overlapping at least 6 inches, and sealed with moisture-resistant tape.There must be a minimum of 18′′ from the ground to underside of joists, the polyethelene should also extend at least 6" up the block walls and be sealed there as well, and it should have perimeter venting equal to at least 1.5% of the crawl space total square footage. The vents should be properly placed for cross-ventilation. We recommend you read this document about what happens when crawl spaces are not sealed.
Important Note About Installing Over An Unconditioned Space (such as a garage): Subfloor moisture penetration of improperly sealed sub-floors over unconditioned spaces is a common cause of wood floor failure. If you are gluing the floor down over such a space, you must use a 100% urethane adhesive that contains a moisture barrier. If you are nailing the floor down over such a space, you will need to follow these steps:
In an unfinished space, staple a 6mm plastic sheet to the ceiling of the unconditioned space with joints overlapping at least 6 inches, and seal with moisture-resistant tape. In a finished space, coat the ceiling with two layers of high-gloss paint.
Lay down two layers of 15 lb asphalt saturated felt paper at a 90 degree angle to each other over the plywood before beginning the nail down installation. Thus, lay down the first layer and be careful not to overlap the rolls as this may cause an un-level surface. Once the first layer is down, install the second layer at a 90 degree angle and care not to overlap
Our solid (wood all the way through) floors can be put under cabinets if they are being nailed down or glued down. Floating floors of any kind should not be installed under cabinets. This is because you do not want to pin down an entire side of a room of floating floors as it will inhibit their ability to expand and contract naturally.
Properly manufactured bamboo and eucalyptus floors (like ours!) are similar to mid-range hardwoods when it comes to dimensional stability, so they can be installed in all climates whether very dry or very humid. Our floors have been installed around the world from the jungles of Kenya to the heights of the Rockies.
All wood flooring expands and contracts with the seasons due to changes in humidity - there are no exceptions. The key is to control your interior humidity as to avoid excessive swings in humidity throughout the year, as these will cause expansion and contraction in your wood/bamboo. The recommended humidity setting for our floors is 40%-60% in humid climates and 35%-55% in dry climates but even dryer and more humid settings may suffice as long as your humidity is stable (within a 20% range) throughout the year. We do recommend to try to keep the humidity above 20% in most cases. In very humid or very dry climates, just follow these tips and you will be all set:
a. Acclimate your flooring for at least 10-14 days prior to installation (instead of the normal 72 hours) in the environment in which they are going to be lived on. Ensure all boxes are opened properly so that the planks can breathe.
b. Glue the flooring down. The elasticity in the glue allows the floors to breathe easily through humidity changes.
c. Make sure to leave ¼ - ½ inch of expansion gap around your flooring perimeter at the time of installation.
d. Try to keep your interior humidity setting consistently in the same 20% range year round (opening windows for a day won't hurt the floors), even via the use of humidifiers/dehumidifiers if necessary. If you allow big humidity swings, larger gaps may develop between your planks during dry spells and they'll close during wet spells.
Although many of our clients have installed our floors over radiant heat over the yeasr, we don't provide a warranty for such installations. The reason is because there are many different types of radiant heat systems on the market,and some can be more difficult to control than others, resulting in extreme temperatures and damage to wood floors.
If you do choose to install our floors over radiant heat we recommend you read the National Wood Flooring Association's protocols for installing hardwoods over radiant heat subsystems, and follow the guidelines below.PRIOR TO INSTALLATION – RADIANT HEAT SUBFLOORS
-6 days prior to installation, the temperature of the radiant heat system should be set close to or at its maximum temperature and kept hot for 72 hours. This is very important because it allows enough time for any remaining moisture to evaporate from the system, attaining its final moisture content.
-At least 72 hours before installation, the heating system must be reduced to a suitable temperature of at least 65° Fahrenheit. If the temperature of the surface slab is below 65° Fahrenheit, the adhesive bond will be affected when the floor is installed by glue-down method.
-Make sure to leave 1/4" - 1/2" of expansion space between the flooring and the walls.
-The temperature of slab should always be maintained at a minimum of 65° Fahrenheit.
-A stove or any other item that can affect the temperature of the ground should not be used at the job site.
-The flooring must be acclimated over the radiant heat with the system turned on. The same acclimation preparation must be followed as always, including cutting the boxes open and stacking them as prescribed in the Acclimation section of this document.
-If the radiant heat system is encased in concrete or another substrate that releases moisture, a 6mm polyethelene barrier must be placed between the flooring boxes and the substrate so that the flooring does not absorb moisture during acclimation
AFTER INSTALLATION / MAINTENANCE
-During the first three days after installation, the concrete slab temperature should be maintained at a minimum of 65° Fahrenheit. After that, the temperature can be set warmer, by 1.5° Fahrenheit each day, with a maximum temperature of 85° Fahrenheit.
-The temperature of the sub-floor must never exceed 85° Fahrenheit and the radiant heat system liquid must not reach more than 112° Fahrenheit during the life of your floor.
-The radiant heat system cannot fluctuate in temperature rapidly. Room temperature should vary no more than +/-7 degrees Fahrenheit year round.
-Slight changing of color is expected for hardwood flooring installed over a radiant heating systems
The U.S. Green Building Council actually ranks varnish and lacquer as two of the worst offenders in terms of VOC off-gassing, so your wood furniture may be emitting more than your wood floors. Federal laws call for varnishes to include less than 450 grams of VOCs per liter, and they require less then 350 grams per liter for lacquers. All of our products meet the CARB Phase 2 indoor air standard and we test them on a yearly basis, at random, using a third party U.S. laboratory. Click here to see all of our test results.
We recommend that you only use 18 gauge cleats. If you use 16 gauge cleats they are likely to cause dimpling on your floors, as described in this article: https://www.ambientbp.com/pdf/avoiddimpling.pdf
Furthermore, they may cause cracks and splits in the tongue that will cause further issues down the road.
We see what you're trying to accomplish but there really are no vapor barrier underlayments used under nailed down floors because once you nail through any underlayment it nullifies it as a vapor barrier. The 3 in 1 underlayments are only used under floating floors, they don't work under nail downs because the compression of the foam results in nails coming loose over time.
Usually in a finished basement the humidity doesn't affect the hardwoods on the main level above it, unless the basement is excessively wet due to a high water table, uncovered ground layer, or similar problem.
That being said, if there is any concern about a basement having excessive humidity, we recommend putting a portable dehumidifier right in the basement. Different humidifiers will condition different sized spaces so make sure you buy one that's big enough for your entire basement. We've also heard of folks taping 6mm or thicker polyethelene sheeting (tarp) to the ceiling of the basement but that can get tricky.
In cases where the basement humidity is slightly elevated we've also heard of installers laying down two layers of 15 lb felt paper under the flooring first (on top of the subfloor), with the second layer of 15 lb felt being laid in a perpendicular fashion to the first, to help "wick away" moisture from the floors. Please note however that the 15 lb felt paper is definitely not considered a vapor barrier, it just helps wick away some moisture.
If you have a humidity modulator in your home that will keep your indoor humidity at a level of 40%-60%, you do not have any run limits on your floating wood floor. This can also be achieved via the use of a portable humidifer or dehumidifier. Also, some areas in the Southern United States have relatively stable humidity year around (like Southern California or Florida) so this usually isn't an issue in those areas. However, if you live in an area with seasons, and you don't have a way to control your humidity, you will want to ensure to follow the guidelines in the diagram below.