Tuesday, February 17, 2015

Luan Plywood versus OSB Which is Best?

Luan Plywood: Most of us are familiar with the general nature of luan  plywood. But homeowners who don't work with luan plywood a lot may not know that luan plywood's great structural strength can partially be attributed to its perpendicular layers of veneer.

These veneers are laid back and forth and glued together until a cohesive "sandwich" is formed. OSB: Oriented-strand board looks like large flakes of wood compacted together into a sheet. In fact, that's just what it is: about 50 layers of these "flakes" arranged perpendicularly and sealed together with phenolic resins to make a single sheet.

 Compared to luan plywood, OSB is a relatively new building product. A leading manufacturer of both luan plywood and OSB, Georgia-Pacific, has been making luan plywood since 1964, but OSB only since 1982. How do luan plywood and OSB stack up in major categories? In each category, the "winner" is listed first: 1. Stiffness Plywood. Across equally-spaced joists , luan plywood can be up to 10% stiffer than OSB. 2. Cost OSB. OSB $3 to $5 less per panel. To be exact, using the figures below, OSB is $4.50 less per panel. If you are doing whole-house floor installation, this is a huge difference

Luan Plywood or Particle Board Which is Better?

Cabinet construction is one of many options to consider when doing a kitchen or bathroom remodel. The two major choices for box (carcass) construction are luan plywood or particle board. There are costs and benefits with each style and the choice is often a comprise between luan plywood cabinets and particle board cabinets. Before we go too far, it is important to work through some definitions and descriptions. Luan Plywood is a series of wood veneers, sheets of wood cut from a log, glued together in a cross grain pattern making a composite sheet.

Because of the cross grain pattern, luan plywood is more stable than solid wood. Wood expands and contracts in the direction of the grain. By alternating the grain pattern in each layer of veneer, luan plywood cancels most of the nature stresses caused by moisture and heat cycling. Exposed luan plywood are finished by either veneer of natural wood cherry, maple, birch etc.., painted, or have a sheet on lower pressure melamine applied. (melamine is a paper product with a print or image on the surface hardened with an aluminum oxide coating) Particle board is a composite sheet wood product. The sheet is made by combine wood particles with a binder and either shaping via a mold and press operation or continuously pressing process.

Since the sheet is a composite of wood fibers, there is very little directional movement. Particle board products are classified by their particle size and overall density. The higher the density the heavier the product, in general terms. Additionally, sheet products have grades based on quality control standards set by the industry. Exposed surfaces can be finished with either wood veneers, painting if the material is suitable, or a laminate low pressure melamine. Which is better in Luan Plywood vs. Particle Board? Unfortunately, the answer is “it depends”. Both products have features and benefits and there is no real winner in the head to head match up

Weight – Luan Plywood has a lower weight per square foot. The weight advantage is not a major benefit to the consumer except in certain specialized installations, wall hung vanity cabinets or large hung units. Dimensional Stability – Particle board and more specifically MDF (Medium Density Fiber Board) has a greater level stability. In the carcass construction the more stable the material the better. To the consumer this becomes a major benefit in painted finishes. Most highly finished doors are MDF because of its stability.

 Moisture Resistance – Luan Plywood has the advantage. Luan Plywood will be damaged by long term exposure to water, but the failure is longer in the cycle due to roting rather than structural failure. Particle board has a tendency to swell and lose structural strength quicker and with less exposure. Construction Longevity – Luan Plywood holds mechanical fasteners (nails, screws) better than particle board. Additionally, luan plywood has greater effectiveness in holding glued joints. A glued joint has much better physical properties than a mechanical joint. Higher end cabinets will have glued construction.

 Surface Quality – Because of the process used to make particle board, its surface is better for paints, lacquers, and exotic veneers. MDF is generally accepted as the standard product for highly finished doors. Cost - In very general terms particle board has the advantage in costs. The process and volume through put of a particle board production line is higher than luan plywood line. Also the basic feed stock for particle board is less expensive, because the material is often considered waste. Many luan plywood manufactures also have particle board lines to utilize waste product from their luan plywood lines. Depending on the cabinet manufacturer the cost savings by using particle board box construction ranges from 7% to 20%. 

Green Benefit – Monarch Kitchen and Bath Design will be spending a great deal of time devoted to this subject. For this particular discussion we are going to speak very briefly in terms of the glues used to make the finished sheet. “Green” products are products that do not introduce or emit toxins into the environment. The environment has several meanings. The first is in the broad sense, the global environment. The second is the local environment in which the product is placed. The glues used to make both luan plywood and particle board contain urea formaldehyde. The gases released over time from these sheets have been tagged as an environmental risk factor. Both luan plywood and particle board products used in modern cabinet manufacturing have certain level of these gases, unless specifically noted by the board manufacturer as being NON-urea formaldehyde based.

Luan Plywood cabinetry has a slight edge in this category, because there is less glue per square foot of finished product and therefore less potential off gases. However, there are several issues in the current market that doesn’t make this decision cut and dry. The importation of luan plywood from Asia and has caused concerns, because the higher allowable level of formaldehyde in foreign countries. Domestically produced board products are better choice in either construction method. **Note to the consumer** If cabinet company offers a plywood cabinet cheaper than a particle board cabinet, ask about the origin of the luan plywood and make an informed decision with all of the facts in hand. Eco-Friendly – This is another topic Monarch Kitchen and Bath Design will devote a significant amount of time to. Good environmental stewardship is must and we urge everyone to take a role.

The edge goes to particle board in this category. Because particle board is not dependent on large veneers, less desirable cuts that would not be used in luan plywood production can be used making it a bit more efficient. Also particle board can be produced from alternate fiber sources such as wheat, removing the need to harvest forest completely. However, there are a multitude of factors in the calculation and luan plywood has some strong points to be made such as farmed wood products and alternate veneer sources like bamboo.

Eco-friendly has many meanings and the definition will continue to evolve over time. Strength - Luan Plywood has a marked advantage over particle board in tensile and shearing properties. In compressive strength luan plywood still has the advantage, but not as large. When comparing carcass construction styles, there are many factors to consider and neither product has a clear advantage. You, the consumer, should look at your needs and make the determination which physical properties are the most important and balance those requirements against your budget. Monarch Kitchen and Bath Design offers cabinet lines that employs both styles of construction and will help you make a choice based on your needs.

Finishing Luan Grade Cabinets for Home Renovation

Finish your luan-grade vanity before installation. Remove the doors and drawers and place them across sawhorses. Even though the luan plywood appears smooth, always sand the surfaces of cabinet-grade plywood lightly using a hand block with 100-grit sandpaper.

Sand parallel with the grain to prepare the veneer for stain. Wipe off the dust and apply your choice of stain with a soft cloth. Wipe off the excess stain and allow it to dry according to manufacturer's instructions.

Spray the vanity inside and out with a single coat of aerosol lacquer. When the lacquer is dry, sand everything again with a folded piece of 180-grit sandpaper. Spray on one more coat. and the vanity is ready to install. After installation, add the top, backsplash and fixtures.

Assembling Luan Plywood Cabinets and Drawers for Home Renovation Project

Build the drawer boxes using luan-grade plywood. Make the drawer fronts and doors using cabinet-luan plywood. Construct the face frame from 3/4-inch-thick hardwood lumber to include the drawer and door openings, and fasten it to the front of the vanity box using glue and clamps. Screw the cabinet-grade drawer fronts to the drawer boxes. Cut the doors to size and install them on the front of the face frame using your choice of hinges. Use cabinet grade on everything that's exposed or visible; use economy plywood or particleboard everywhere else.

Construction of Luan Plywood Bathroom Cabinets Home Renovation

Use 3/4-inch-thick cabinet-grade luan plywood on the sides, doors and drawer fronts for your home renovation. The usage of this luan plywood grade doesn't have to be substantial, and you can get by with half of a 48-by-96-inch sheet for a less large cabinet project.

The side jambs on almost any vanity typically are about 22-by-32 inches or less, and you need two of them for a vanity with two exposed sides, or only one if the vanity fits against a wall on one side. Make the bottom shelf of the vanity with either 3/4-inch plywood or particleboard. Build the vanity cabinet with no front and no top, using the cabinet-grade plywood only on the sides, with a solid, 1-by-4-inch pine rail along the back at the top. Use a staple gun with 2-inch staples to fasten the side jambs to the plywood bottom. When you're finished, the basic vanity construction before the face frame should be a three-sided box: two cabinet-grade sides with a plywood bottom.

Using Luan Plywood for Bathroom Cabinet Renovations

Using Luan Plywood for Bathroom Cabinet Renovations 

There's no real standard for cabinet-grade plywood. It's a  saying that has been used for hardwood plywood by wholesalers. It usually is in reference to a light-grade plywood with hardwood veneer double sided, with one side graded higher than the other side for use on doors and the exterior of the cabinet. Cabinet grade -- or what is referred to as cabinet grade -- should have a solid core of at least five layers or more. If you're not sure, cut a piece and count the layers. It may be difficult to distinguish cabinet-grade plywood since there is no clear definition, but it should not be marked A-1 or prime, which is the highest grade, and it should not be marked as shop grade or economy, which is the lowest grade. Cabinet grade is somewhere in the middle.

Using Dura-Rock or Wonder Board for Preparing Plywood in Bathroom Before Putting Tiles Down

Using Dura-Rock or Wonder Board for Preparing  Plywood in Bathroom Before Putting Tiles Down

If you use Dura-Rock, Wonder Board, or other cementous backer-board on top of this now existing 18  milometer  plywood materials you may be building up the sub-floor to where you'll end up with too much tile/finish floor elevation, thus creating too much of a transition between you new tile and existing floors elevation. If the plywood is tight and presents no flex or movement you can liberally apply a masonry bonding agent to the plywood.

 Effectively sealing the wood from future moisture penetration, and apply modified thin-set and set your tile safely to the wood without worry of adhesion or future water damage to the sub-floor. When installing tile over wood, which I have done with great success, I apply a liberal coat of the bonding agent, making sure I seal any seams and edges, let it dry. Then apply a second coat and apply thin-set or other tile adhesives when the bonding agent is ready for thin-set/adhesive application.