Glue-Down Method

Note: THE FOLLOWING IS A GUIDELINE ONLY. CAREFULLY READ THE MANUFACTURER’S INSTALLATION INSTRUCTIONS THAT COME WITH YOUR PRODUCT BEFORE BEGINNING THE INSTALLATION.

Installer/Owner Responsibility

Hardwood flooring is a stunning natural product with inherent variations in appearance. It is the owner’s and installer’s responsibility for all products installed.

Before the actual installation, the installer and/or owner have to assume responsibility for inspecting the flooring as to grade, manufacture, color and finish. Another responsibility applies during his/her absence from the installation site. Keep in mind that if a flooring board is not acceptable, you should not install it. The next step is contacting the seller. Once a board has been nailed or glued down, it is deemed accepted by the installer and/or owner. Usually, manufacturers deny any responsibility for judgment errors and/or for poor installation quality of their products.

Tools and Accessories Needed:

• Industry Standard Adhesive
• Trowel
• Concrete nails (to secure holding block)

• Blue adhesive painters tape

Temperature, Humidity, Storage and Handling

We all know that hardwood is a living material that naturally reacts to changes of relative humidity. According to each season, hardwood absorbs or releases humidity. The heating/air-condition system must be operational for least 14 days prior to installation and thereafter at a temperature of 65°F – 75°F to reach desired humidity level. The relative humidity level at home should be controlled between 35% – 55% at all times prior, during and subsequent to installation.

When humidity is high, hardwood absorbs the humidity in the air and expands, this causing the strips/planks of wood to push against each other. The floor is cupped or “cupping”. Proper ventilation could minimize these variations.

In winter, the relative humidity level is lower due to the usage of heating system. The lower humidity level results the wood releases its humidity and the strips/planks contract or shrink. We recommend to use a humidifier to minimize extreme shrinkage effects.

Keep in mind that hardwood flooring has to be stored in a controlled environment. Furthermore, materials should be delivered 72 hours prior to installation for the hardwood flooring to acclimate. Acclimation within a closed carton may not be adequate due to lack of air movement. You have to store the flooring in a dry place and provide air space under cartons. Remember to never unload or transport flooring during wet conditions. We already explained how the wood absorbs moisture, which causes it to swell.

Job Site Requirements

The building must be completely closed in with all outside doors and windows in place while the wall and painting should be covered before starting the installation.

Furthermore, you need to make sure basements and under-floor crawl space are dry and well ventilated. In addition to that, plastering and concrete work must be completely dry with minimum of 90 days curing time.

Exterior grading should be complete with surface drainage offering a minimum drop of 3″ in 10′ to direct flow of water away from the structure and all gutters and downspouts should be in place.

Remember the overall rule which let’s us know that solid hardwood flooring can only be installed on or above ground level with a plywood subfloor while engineered flooring can be installed above grade, at grade and below grade level.

Never install hardwood flooring in bathrooms. Check with the manufacturer’s instructions to determine if your hardwood floor can be installed over an in-floor radiant heat system.

Another thing you should have in mind is that crawl spaces must have a minimum of 24″ from the ground to underside of joists. A ground cover of 6-8 mil polyethylene sheeting is essential as a vapor barrier with joints lapped six inches and taped. The crawl space should have perimeter venting equal to a minimum of 1.5% of the crawl space square footage. These vents must be properly located to foster cross ventilation. In some cases, local regulations must be met. Another important thing is that crawl spaces must be dry and well ventilated. Check the plywood (subfloor) moisture content by using a moisture meter. Delay the installation if the moisture content of the plywood (sub-floor) exceeds 12%.

Engineered flooring can be installed over a dry concrete subfloor. If you want to test the moisture level of the concrete subfloor, tape 18″ x 18″ clear plastic sheeting to the floor in two spots, sealing all sides with moisture resistant tape. Leave in place for 48 hours and then remove. If there is no condensation on the underside of the plastic sheeting, the concrete slab can be considered dry enough to install the engineered flooring. If there is moisture on the plastic sheeting, there is a problem and the flooring cannot be installed. A professionally installed moisture barrier would be required. Using the moisture meter, check the moisture content of the hardwood flooring to ensure that it is within the acceptable moisture range of 6% to 9%. The installer and/or owner has full responsibility for moisture testing the wood or concrete subfloor and the hardwood flooring prior to installation.

Job Site Requirements

• Preferred ¾” CDX grade plywood with minimum of 5/8″ CDX grade plywood over joists subfloor.
• Existing wood boards over joists subfloor and
• Dry Concrete subfloor (only for Engineered Hardwood Floors)

Note: particle board or other similar type products are not suitable sub-floors.

Sub-flooring has to be clean, smooth and free of wax, paint, oil, sealers, adhesives, curing agents and other debris. Another rule is that sub-flooring has to be straight, flat and leveled. Sand high areas or joints. Flatten low spots with layers of builders felt, plywood or shims. Furthermore, sub-flooring must be structurally sound. Nail or screw any loose areas that squeak. Keep in mind to replace any damaged, swollen or delaminated sub-flooring.

Another rule is that the sub-flooring must be completely dry and respect the moisture content requirements. Sub-floor preparation is one of the most important steps before the installation of your new floor. Remember that the hardwood floor is only as good as what is underneath it. Laminated rosin paper or construction paper acts as a moisture retarder. This could be used to reduce the movement caused by changes in subfloor moisture. It could also reduce sound transfer and prevent noise.

General Instructions Before the Installation

• It is recommended that the flooring should be installed at a 90 degree angle to the joists for wood subfloors.
• An additional 5% flooring must be added to the actual square footage. This is needed for cutting and grading allowance.
• The flooring should be installed from several cartons at the same time. This ensures good color and shade mixture.
• Remove any existing base molding, other moldings, door sills and old floor covering where applicable. By using a hand saw, undercut the bottom of door frames 3/4″ to slide hardwood board beneath.
• It is the installer’s/owner’s responsibility to ensure that the conditions of the flooring are acceptable prior to installation. So do not use flooring pieces with obvious defects. Manufacturers generally decline any responsibility for flooring which is installed with obvious defects.

Glue Down Installation Guidelines (Only For Engineered Floors)

• Make sure that all the conditions from above have been respected. Now just determine a starting point. Begin the layout from the straightest wall (which is usually an outside wall). Now you need to measure out from this wall at each end the width of two boards (including the tongue) and then add an additional 3/4″ for expansion. You next have to mark a chalk line parallel to the starting wall, this being the starting line for the placement of the floor. Note: The working area between the starting wall and the chalk line will be the last floor area installed. We recommend holding block to be nailed down or secured between the chalk line and the outside wall to secure the first row of floor. This has the purpose of preventing movement.
• Apply the adhesive to the sub-floor area in accordance with all manufacturer’s instructions. The adhesive has to cover the width of approximately the first two rows of planks. Make sure that the room is well ventilated and spread the adhesive holding the trowel at a 45 degree angle to the sub-floor. Remember to limit the application of adhesive to the subfloor to the area which can be covered in 30 minutes in order to prevent drying out of the adhesive. Anyway, the drying time might vary.
• Use the longest, straightest boards for the first two rows and leave a ¾” gap alongside both the left wall and right walls. They are perpendicular to the starting line to serve as expansion gaps. You need to install the first row of planks along the chalk line/holding block with the tongue side propped against the holding block, and press the board down for adhesion to the subfloor. Make sure that a long board is chosen as the last board of the row. The cut portion of the last board can be used as the starting board of the next row.
• Carefully start the second row after making sure that the first board which was used for the second row is at least 6″ longer (or shorter) than the board of the first row. You now need to insert the tongue end of the second row board into the board groove of the first row board and slide securely into place. The next step is pressing the board down for adhesion to subfloor.
• Follow the same method for the installation of subsequent rows. Remember to be careful to stagger the end joints by at least 6″. Remember not to walk on the freshly installed floor. Apply blue adhesive painters tape perpendicularly to the seam of adjoining rows to prevent the rows from spreading apart. Any adhesive which gets on the surface of the flooring should be removed immediately by using damp, clean towels and followed by drying the cleaned surface. Replace the towels for effective cleaning.
• When installing the row adjacent to the end wall leave an expansion space of approximately ¾”.
• After installing the end wall row, go back to the area between the starting wall and the chalk line. You have to remove the holding block and proceed to glue down the first two rows between the chalk line and the starting wall. Your measurement from the starting wall already should have provided for a ¾” expansion space. After finishing the installation wait 24 hours before walking on the floor. You can now move back your furniture and additional objects.

Complete the Installation

• On of the final steps of the installation is vacuuming and cleaning the floor with proper wood flooring cleaner on a soft, cloth mop.
• Now wipe the area clean in order to remove loose dirt or soil.
• Reinstall all base and/or quarter round moldings. Nail the moldings into the wall, not the floor.
• Don’t forget to install any transition pieces that may be required (such as reducers, T-moldings and stair nosing).
• In the end remember to keep a few spare boards in the event of future repairs.