Installation + Storage Guidelines
Panels, Veneer and parquet Butcher Block
countertops
The following information applies to Teragren bamboo panels, butcher block and veneer. It has been compiled to assist with finish selection and with understanding how basic wood installation, storage and finishing techniques apply to installing and finishing bamboo as countertops and tables.
Installation Precautions
Expansion and Contraction
Teragren panels and butcher block are manufactured at a moisture content of 6% to 8%. Occasionally they may take on additional moisture in transport, especially in the spring and fall, and slight warping may occur. The wider the panel, the greater the expansion. This is only temporary; once your panel has become adjusted to its new surroundings, the moisture content will equalize and the panel will straighten out. Under normal conditions the panel will return to the original dimension during the winter months and will expand during the summer months when the humidity is greater. A solid wood top that is 30" wide can expand or contract by 1⁄16" to 3⁄16" in varying weather conditions. Your custom top needs to be installed in a manner that allows for such movement.
Warping
Warping is caused by the expansion of either the top or bottom surface. For countertops, this condition is easily corrected by placing the panel on the cabinet base and drawing the panel or butcher block down to a level position by attaching screws. All counter panels or block should be attached to bases on or at least near all 4 corners. Should the warp be too severe to fasten down, allow both sides of the panel to be exposed to the same atmosphere to acclimate. Warping is a temporary condition that will be corrected as the moisture content of the panel is equalized on both top and bottom surfaces.
Attaching Countertops
Do not set the countertop with adhesive caulk; the top must be securely fastened to the base unit with appropriate length wood screws. The top should be attached in 3 places across the width (on the front edge, the middle, and at the back edge). It should also be attached at approximately 12" intervals throughout the length of the top.
Most cabinet manufacturers provide corner blocks within the cabinet for attaching the countertop to the cabinet base, and pilot holes should be predrilled through the corner blocks into the underside of the top. Be careful that you do not drill too far into the top. Where it is not possible to attach the panel to a cabinet base using corner blocks, attach several angle irons to the underside of the panel and to the inside of the cabinet casework, as close as possible to the corners. Where the top does not rest on a cabinet, it must be supported by strips of wood. If your top contains multiple pieces, ensure the corner fittings have been tightened after the top has been installed. Be sure to allow for expansion and contraction of the panel or block.
Some manufacturers of cabinets and appliances take into consideration expansion and contraction by slotting the screw holes. If your pilot holes are drilled at the extreme ends of the slots and the block expands or contracts, you negate the advantage of the slots. Where a manufacturer has not made such allowances, you should use an undersized screw with a washer or make the pilot holes oversized (3/8" larger in diameter than the screw) using a flat head screw and a large washer. Do not over tighten the screws as this will restrict the natural movement of the top. Larger panels may expand or contract as much as 3/8". Here again, the rule of thumb is the bigger the block, the greater the expansion.
If you are installing a back splash along with the countertop, it is advisable to attach it at this time. The back splash is usually attached to the surface, not to the back edge that would be against the wall.
Cut-Outs and Cut-offs
After any finish has been applied, whenever a panel is cut either for size adjustments in length or width or for sink or cook top cutouts, the cut edge needs to be finished at once to prevent possible cracking. For cook top cutouts, applying an aluminum heat reflective tape with attached insulation after the edge has been refinished will dissipate heat into the cabinet below. This also will allow the top to expand and contract more evenly.
Split Ends
This condition is caused by the contraction of the butt ends and not that of the center part of the panel. It could be a sign that your home is too dry or the panel was not properly sealed. Determine what the relative humidity is and make proper adjustments. These cracks should be filled promptly with wood filler, sanded smooth, and finished with a protective finish. Split ends can also be caused by not allowing for expansion and contraction when attaching items to the panel. Relieve tension at once by removing screws and repair splits as suggested above.
Condition and Color
Teragren bamboo panels and butcher block are unfinished and sanded to 180 grit. Profiles can be easily routed to any style. Please note that bamboo is a natural fiber and material will have natural variations in color from sheet to sheet and within sheets. Teragren is not responsible for any costs or expenses incurred during installation or removal of defective pieces due to warping, splitting or any other reasons.
Please reference the Architectural Woodwork Institute (AWI) Quality Standards on Relative Humidity and Moisture Content for additional guidance.
Finishes
Finishes enhance the beauty and extend the useful life of wood. Wood is hygroscopic which means it will take on and lose moisture throughout its lifespan. As a natural living material, wood is affected by cold, heat, and humidity. A finish inhibits and evens out the movement of moisture in and out of the panel. Without finish the wood will act naturally and attempt to move moisture within itself. If the wood dries out rapidly, its surface dries faster than the inside, resulting in cracks and checks. If too much moisture is soaked up, it swells and warps. The longer a panel remains unfinished and the greater the difference in environment, the greater the chance the panel will develop problems. This is natural and is not considered a manufacturing defect.
Finish selection is based on the qualities of wood protection and durability for the intended use. Water-repellent finishes will reduce the effects of brief periods of moisture (washing) and liquids, making the wood easier to clean. Finished wood countertops are less likely to show stains. For information on the safety and toxicity of any finish, check the label and/or contact the manufacturer.
Commonly used wood finishes include wax, shellac, drying oils (such as linseed oil or tung oil), lacquer, varnish or paint. Other finishes called "oil finish" or "Danish oil" are actually thin varnishes with a relatively large amount of oil and solvent. Water-based finishes can cause a raised grain that requires sanding down. A number of finish coats are often applied, sanding between coats. Finishes should be applied to all surfaces to maintain moisture balance.
Drying oils are some of the most recommended finishes. Drying oils penetrate the wood and harden the material. They reduce water absorption and make the surface easy to clean and resistant to scratches. Drying oils are considered some of the most satisfactory finishes for wood surfaces and they include linseed oil, tung oil and diluted varnish.
Vegetable Oils (e.g., olive, corn, peanut, safflower) are edible and sometimes used to finish wood utensils. Walnut oil is particularly suitable. These natural non-drying oils are applied heavily in several coats and can be refurbished easily. However, they run the risk of going rancid and can be a health issue.
Mineral Oil is a petroleum-based, non-drying oil that has long been used as a penetrating finish for wood utensils and food preparation surfaces. Mineral oil remains safe throughout its life. As a kitchen sealer, traditional mineral oil is both food and environmentally safe. To prevent drying, re-oiling is required maintenance but its frequency depends upon environment and use. Baby oil should not be used because it contains some ingredients that should not come in contact with food.
Paraffin Wax. One of the simplest ways to finish wood is to apply melted paraffin wax (the type used for home canning). Melt the wax in a double boiler over hot water and liberally brush on the wood surface. Excess wax may be left on or scraped off as desired. Heating the excess wax on the surface with an old iron (similar to waxing skis) helps improve absorption of the wax. Wax is often used over other finishes such as lacquer or shellac.
Seal the underside prior to installation to help resist warping and prevent moisture absorption.
Finishes may be polished or buffed using steel wool, pumice, rottenstone and other polishing or rubbing compounds depending on the sheen desired.
Give extra care and attention to sealing edges when panels or butcher block is to be used around sinks. Prolonged or constant exposure to water can cause darkening of the wood and over-saturation that in turn causes warping. Teragren recommends installing a non-porous material such as stainless steel or tile around sinks as a transition to the wood.
Due to varying application environments and situations, these guidelines do not guarantee results and should be used a supplemental source of information. It is the responsibility of the design professional to engineer the space in which fine woodwork (not to mention laminates, fabrics and wall coverings) is to be installed with appropriate controls to maintain optimal humidity for your area. As with any product, follow the manufacturer's application recommendations and test to ensure desired results.
Use and storage information
Uses
Teragren manufactures furniture grade bamboo panels and veneer for interior applications. Intended uses as architectural woodwork or casework may include cabinetry, furniture, interior paneling, counter tops, and any other interior application where hardwood products have traditionally been used.
Handling & Storage Recommendations
Carry light weight panels on edge or support horizontally to prevent cracking along the grain. The following basic steps in handling and storage are recommended to help avoid or minimize some of the problems associated with wood movement.
Panels should be stored flat on raised runners of equal thickness. ▫ Humidity and temperature controls that are capable of maintaining a constant 40 to 60% relative humidity and 65 to 75°F should be installed. ▫Extremes of heat or cold as well as dry or humid conditions should be avoided. ▫Panels stored in an uncontrolled environment should be brought into the fabrication area 24 to 48 hours prior to being processed. Again, they should be stacked flat on raised runners of equal thickness. Evenly distributed weighting of the stack will help the panels acclimatize uniformly.▫Sanding by the fabricator prior to finishing is always recommended. ▫ All exposed panel surfaces should be sealed. ▫Allowance for expansion and contraction should be incorporated into the design of the product. ▫ Panel products should not be taken to a job site until the site is completely ready for the product to be installed. They should be allowed to acclimate to the job site before installation. ▫ Wall panels should not be installed over wet or unfinished drywall.▫ The finished product should not be installed until after the Heating, Ventilation, and Cooling (HVAC) system is on line and functioning. Source: A Complete Guide to Hardwood Plywood and Face Veneer, Trouble Shooting Common Problems Chapter VIII
Recommended Cutting Instructions
Sharp carbide tip blades are recommended. Bamboo machines easily in the long direction with the grain. It can splinter when crosscutting, coping and tenoning across the end grain. If a crack develops, due to the linear-fiber grain structure, it can run the entire length of the board. Bamboo sands well with a wide belt sander or a profile sander.
Finishes & Adhesives
Bamboo takes a sealer and finish very well. Many finishes and adhesives suitable to the cabinet and furniture manufacturing industry have been used successfully with bamboo. Independent testing was performed to ensure the adhesive between the bamboo slats on the panels is compatible with Methyl Alcohol and Methyl Ethyl Ketone-based products. The adhesive used to adhere the backing of our 1/42” paper-fleece backing meets specifications as a D-4 waterproof glue. Veneer must be bonded to a suitable substrate of a reliable quality. MDF (medium density fiberboard) is the most stable substrate, followed by industrial particleboard, veneer-core plywood, and the least stable substrate - hardwood. Direct application to drywall, plaster walls, concrete walls or cardboard products is not recommended as delaminating may occur. Veneer should be applied to MDF substrate to cover these surfaces. Installation over substrates that have been treated with a fire-retardant agent is not recommended. If using a hot press method to laminate veneer, the best temperature is 120 degrees Celsius. For hot pressing panels 1/8” and thicker it is best to use temperatures under 100 degrees Celsius. When applying finishes, follow manufacturer’s suggested temperature and thickness for application. Testing the adhesive or finish you wish to use to ensure the overall compatibility between the treatment, the panel, and the installed environment is recommended. Please note that the adhesive used to manufacture our standard panels and veneer is not food grade. If the surface is to be used for food preparation, a food grade sealer is recommended. Our butcher block is manufactured as food safe and all panels and veneer may be special ordered with a food safe adhesive.
Dimensional Stability of Teragren Bamboo Panels
1’x6’ Single Ply Panels: ASTM D 1037: dimensional change coefficient: 0.0014. 4 x 8 x ¾” Multi-ply Panels: AR/50/90 ASTM D 1037: 90% RH: Avg. perpendicular linear expansion .063%, Avg. parallel linear expansion .086%, Avg. perpendicular thickness swell .746%, Avg. parallel thickness swell 1.061%. Delivered moisture content approximately eight (8) percent.
Due to varying application environments and situations, these guidelines do not guarantee results and should be used as a supplemental source of information only. Please review our Product Specifications and Material Safety Data Sheets for further information. All information is available on our web site at www.teragren.com. For more information about relative humidity and its relationship to moisture content, please reference the Architectural Woodwork Institute (AWI) web site at www.awinet.org and the Hardwood Plywood and Veneer Association (HPVA) website at www.hpva.org