Plasticlad® is a thermoplastic material, and responds differently than traditional building components in some situations. For best results, the following guidelines should always be considered when working with Plasticlad®.
Thermal Expansion and Contraction
Plasticlad® is an expanded cellular PVC product that expands and contracts with thermal temperatures. This property is called "linear thermal expansion and contraction". The movement seen in PVC foam material is similar to that of wood movement due to moisture absorption and evaporation.
The basis for determining the limits of expansion and contraction is the overall temperature range in the area where you are using Plasticlad®. For example, if the temperature varies 90 degrees over the course of an average year, your installation must take into account that the material will need to be able to expand in the upper temperature ranges and contract in the lower temperature ranges without buckling or binding.
The most important factor to consider when installing Plasticlad® is the temperature of the material, relative to the overall temperature range, at the time of application. This will determine how tightly you can join pieces, or what size gap should be utilized to accommodate seasonal expansion.
If you are working with Plasticlad® on a day that is in the upper end of the temperature range (75 to 95) the material should be fully expanded. Leaving it in the sun for an hour prior to application should help ensure that it has achieved its full expansion. In this instance, you can join pieces tight, with no gaps required. We still recommend a bevel or shiplap joint for ideal installation. The Plasticlad® will contract as the temperature drops, and some caulking may be desired to fill the resulting seasonal gaps.
If you are working with Plasticlad® on a day of moderate temperatures (55 to 75) the material will be partially expanded. You must allow for some expansion in your installation. The appropriate amount will be determined by considering your working temperature relative to the overall temperature range. An appropriately sized gap, utilizing a bevel or shiplap joint, should be installed, allowing the material to expand without buckling or binding. If desired, a recommended caulk can be used to fill the gap for appearance.
If you are working with Plasticlad® on a day in the lower end of the temperature range (25 to 55) the material will be mostly contracted. You must allow for full expansion when the temperature warms to seasonal highs. The appropriate amount will be determined by considering your working temperature relative to the overall temperature range. An appropriately sized gap, utilizing a bevel or shiplap joint, should be installed, allowing the material to expand without buckling or binding. If desired, a recommended caulk can be used to fill the gap for appearance.
The average expansion and contraction, over the total temperature range, depending on exposure to the sun, should be approximately 1/8" per 12 foot length. In cases where the material cannot be securely face nailed, the gap may need to be doubled.
Expansion and contraction are mainly a consideration over the length of a board. The expansion and contraction over the width of a board is so small that it seldom is a factor, and usually cannot even be measured.
Proper fastening is a critical element in limiting expansion and contraction. Aggressive nailing patterns, minimum 16" on center, can seriously help restrict seasonal movement of Plasticlad®. Fasteners with sufficient tensile strength in the shaft to prevent bending are recommended. Most expansion problems are the result of inadequate fastening, and can be prevented by adhering to a strict schedule of properly spaced nailing. The rule of thumb for fastening Plasticlad® is the more nails you can use to secure it, the less it will move.
When installing Plasticlad® the appropriate size of a gap, if required, is determined by the temperature of the material relative to the overall temperature range.
• Material that cannot be securely face nailed may require larger gaps.
• Material that receives direct sun exposure may be subject to a wider
• Care must be taken not to use Plasticlad® in areas that exceed the service
temperature of 140 degrees, or the plastic may soften and change
• Darker paint colors may exhibit additional solar temperature gain, increasing
expansion and contraction.
• The more nails you use to secure Plasticlad®, the more you will restrict
expansion and contraction.
• Recommended fasteners will have sufficient tensile strength in the shaft to resist
the forces of bending during expansion and contraction. (i.e. stainless steel)
• Expansion and contraction are linear, and have minimal effect on the width of
• Notch Sensitivity
• Sharp inside corner cuts, such as the base of a dovetail, and scored lines can be
easily broken. For best results, a small radius should be maintained to help avoid
any stress cracking. Scoring of the material should be avoided.
Plasticlad® can be fastened using most common fasteners utilized in securing wood to various substrates. It can be hand nailed, power nailed, screwed, and glued using accepted methods and practices. The same precautions that govern the fastening of any material should be followed when working with Plasticlad®.
Plasticlad® can be nailed just like wood. Hand nailing or power nailing is acceptable. Nails should have sufficient tensile strength in the shaft to resist bending during seasonal movement. For best results, a selection of smooth shank, screw, annular threaded, or spiral type nails that are stainless steel are recommended. Hot dip galvanized nails may also be used. Standard nails that are not protected from rusting will cause staining on the material.
The more frequently you nail Plasticlad®, the more you will restrict expansion and contraction. Aggressive nailing, minimum 16" on center, is recommended.
Use of annular threaded nails is not recommended in low temperatures. The friction build up on the threads can cause some material blow out on the back of the board.
When fastening gutters over Plasticlad Trimboards it is best to use screws. As with wood, gutter spikes can cause Plasticlad Trimboards to split when driven close to the edge.
Power nailers are acceptable, and are commonly used to fasten Plasticlad®. Care should be taken not to overdrive the nail into the material. Nail guns should be adjusted to prevent excessive nailing pressure, which can result in cracking. When hand nailing, care should be taken not to damage the board surface with excessive hammer force.
Fastening Outdoors in Low Temperature
Impact properties decrease in low temperatures, making the material more susceptible to cracking or shattering. Care should be taken to avoid excess pressure in these instances. The use of annular threaded nails is not recommended in low temperature conditions.
Bonding and Adhesives
Plasticlad® can be bonded to a variety of substrates, as well as itself. For best results, follow the manufacturer's guidelines, and keep all material clean and dry.
Plasticlad® to Plasticlad® or other PVC
PVC pipe cement or other solvent based adhesives work very well. Be careful to use one with a moderate or slow set up time. Plumber's cement is generally a fast set up time, and may bond too quickly for detail work. Proper ventilation and a clean environment are essential for adequate curing. Bonding large panels face to face requires care, as the solvent based adhesives may not cure properly.
Plasticlad® to various other substrates
There are a variety of adhesives that are applicable for use with specific substrate combinations. Contact cement, epoxy, rubber based and urethane adhesive systems are all generally acceptable. Specific formulations vary with each manufacturer, and performance is dependant on application. For best results, consult the manufacturer's recommendations, and test the application for finished suitability before proceeding.