FAQ's ABOUT SIPS
WHAT DOES SIPS MEAN?
Structural Insulated Panel System. Each panel is a structural unit that is manufactured to a precise engineering standard. The panels consist of an outer and inner skin of a structural OSB or MgO board, which are glued to the expanded styrene foam core. Structural lumber is also incorporated for plates, door and window framing and splines. The resulting product is a laminated panel that is structurally strong and offers a high insulation value. The panels are fabricated at the factory and shipped to the building site for erection.
WHAT IS MEANT BY "STRUCTURAL INSULATED PANEL SYSTEM"?
The SIP system is a design and construction method using engineered panels to build the exterior walls and roof, rather than conventional 2 X 4 and truss construction or other methods of building. Each SIPS package is individually designed to meet the specific requirements of your home or commercial building.
The Structural lnsulated Panels are recognized by code organizations and meet local and national building code requirements. The high insulation value of the SIP System will ensure dollar savings in utility costs. The SIP system is acknowledged by most utilities for their good sense or energy wise programs.
WHY SHOULD I CONSIDER USING THE SIP SYSTEM FOR MY NEW HOME?
SIPS offer many advantages compared to conventional construction. Some of the major advantages include integrity and strength of the finished building, energy efficiency, speed of erection and overall higher quality of the completed building.
lntegrity and Strength: The laminated Structural lnsulated Panel with two skins of structural OSB or MgO provides strength to the exterior walls and roof. The outside and inside layers of OSB or MgO also provides a nailing surface throughout, which eliminates searching for studs while hanging siding, drywall, paneling, shelves, cabinets, etc., thus cutting down on time required. At the construction site the panels are joined using construction adhesive, nails and screws. As a result, the entire structure is a very strong and tight "unibody."
Superior Insulating Qualities: The foam core of the panel provides a much higher R-value in less space than fiberglass or cellulose insulation and maintains this performance indefinitely. SIPS have a THERMAL PERFORMANCE WARRANTY which guarantees the insulating performance of the panel.
SIPS inherently permit significantly less air infiltration. Wall studs in conventionally-built homes transmit some exterior temperature (heat and cold) through the walls and air leakage is common around electrical outlets and switches. The solid foam core and general absence of studs creates a tight building envelope. The precut wiring chases also help eliminate air infiltration.
Speed of Erection: A building can be dried in more rapidly than a site-built stud frame or a panelized open stud frame structure. The use of SIPS reduces labor costs at the building site, construction loan time and cost, exposure to the elements and the opportunity for thievery of loose materials.
SIPS provide structure strength, sheathing and insulation in one component. This not only reduces the number of subcontractors required, but also saves on supervision costs, and administrative overhead.
WHAT FACTORS IMPACT THE ENVIRONMENT?
SIPS are recognized as an ENERGY EFFICIENT and GREEN product. Panels supplied by Xtreme CBS use plantation grown engineered wood materials for most applications and require less dimensional lumber as a whole. This significantly reduces the need for harvesting old growth timber.
The foam core used in the panels is recyclable; thus reducing the need for raw material and reducing the amount of material that may eventually reach our landfills.
Construction scrap is kept to a minimum, thus reducing the amount of construction material waste that will be hauled to the landfill.
WHAT STYLE OF HOUSE CAN BE BUILT USING SIPS?
SIPS construction is suitable for nearly every architectural style and can be used on many types of building sites. SIPS homes can be built on basements, slabs, pilings, and other types of foundations.
CAN YOU ADAPT SIPS TO AN EXISTING FLOOR PLAN?
We can supply SIPS for almost any floor plan. lf you do not already have a plan we can help you design an original floor plan. The use of panels in the roof system provides full use of interior space and offer dramatic vaulted ceilings. Interior space that otherwise would be lost to attics, can be used for lofts and/or heated/cooled storage areas.
WHAT TYPE OF FOAM INSULATION IS USED IN THE PANELS?
Our standard panels have a core of modified Expanded Polystyrene (EPS). EPS provides higher R-values per dollar than other types of foam and does not contain chlorofluorocarbons (CFC5), which are believed to damage the Earth's ozone layer. The R-value of our panels is extremely stable. In field testing over a number of decades EPS has been shown to retain vir-tually all of its original thermal and physical properties. EPS maintains a constant value in either hot or cold temperatures.
IS THE INSULATION VALUE OF THE STRUCTURAL INSULATED PANELS BETTER THAN STUD WALLS FILLED WITH FIBERGLASS BATTS?
Yes. When evaluating the insulating performance of a wall system, several factors should be considered. Most common among these is R-value. R-value is a measurement of the ability of materials to resist conductive heat transfer (movement of heat through solid material). The higher the R-value of an insulating material, the better it is able to resist heat loss or gain. We offers SIPS panels from R-17 through R-41 compared to R-9 which is common in stud built walls.
ARE THERE PROBLEMS WITH CONDENSATION?
Condensation is an area of concem in fibrous insulations. In recent years there has been growing concern about the effects water vapor has on wall systems in tightly constructed buildings. The theoretical basis for this concern is as follows: vaporized water generated by daily living activities penetrates the interior sheathing (usually drywall) and enters the wall cavity. As the vapor contacts the cold outside wall, it can condense into actual water droplets which create the potential for mold and mildew, blistering paint, degraded insulation and even structural damage due to rotted studs.
HOW DO FOAM CORE PANELS DECREASE THIS PROBLEM?
First, the combination of the foam core material used in the panels and the structural OSB skins allows the SIPS to become a vapor barrier without using expensive wraps to protect a structure.
Second, the panels are manufactured in large sheets (from 4'x 8' up to 8'x 24') consisting mostly of insulation. The seams are sealed, creating a continuous blanket of insulation uninterrupted by structural framing members (as opposed to a conventional stud wall with a break in the insulation every 16 inches to accommodate framing lumber).
Removing the framing lumber from the insulation allows full utilization of the EPS. Remember, wood is a relatively poor insulator (R- 1 per inch of thickness); and in a wall with studs every sixteen inches, wood can account for up to thirty percent of a wall's volume, significantly reducing the overall performance of a wall. The stated R-value of a SIP panel is a true refiection of its ability to resist conductive temperature loss.
Third, in SIPS the continuous mass of high density foam nearly eliminates air movement within the wall and the heat loss caused by convective looping of air within the insulation.
Fourth, EPS foam is only marginally affected by moisture condensation. In one test, EPS was force saturated to ten times its normal dry weight and still retained 80% of its insulating value. In addition, EPS insulation is an inert, organic material. lt provides no food value to plants, animals, insects or microorganisms. lt will not rot and is highly resistant to mildew.
I AM BUILDING IN A WOODED AREA. COULD I HAVE PROBLEMS WITH CARPENTER ANTS?
Possibly. If you build your nest in ant territory, they may build their nests in yours. Unlike termites, carpenter ants do not eat wood, they just burrow in it, and the softer the wood, the easier their work. That is why they like moist, rotting limbs and stumps. The OSB is a man-made product which is highly compressed and utilizes adhesives in the manufacturing process. Ants, termites and other insects are not inclined to nest or borrow in the structural OSB skins.
In areas that are particularly prone to ant problems such as heavily wooded areas or low shaded areas where the ground stays damp, consider treating the foundation with a long-acting pesticide prior to backfilling. You may also want to treat the soil around the house after backfilling and install a termite shield under the siIl. Consult a local treatment expert for further recommendations on long term control methods for your area. Structural lnsulated Panel system construction is less prone to insect infiltration than regular stud construction.
WILL EPS GIVE OFF TOXIC GASES IN MY HOME?
No. EPS begins as tiny styrene beads that are impregnated with liquid pentane, a colorless hydrocarbon which does not cause any health problems when used in the relatively low concentration levels as in this application.
When heat and steam are applied to the beads, the pentane causes them to expand to more than 30 times their original size (similar to popped popcorn). When the plastic is in its bead form, pentane accounts for about 6 percent (by weight) of the material. During the expansion process, this drops to about 3 percent: and within six weeks to two months after cutting, the pentane content declines to less than one-quarter of one percent. By the time of occupancy, the pentane content is negligible. EPS foam contains no formaldehyde.
DOES THE ADHESIVE IN THE OSB CAUSE ANY HEALTH PROBLEMS?
In the late 1970's, when concerns about the health effects of out-gassed formaldehyde came to light, many pressed board manufacturers switched to phenolic glues. These glues do contain a minute amount of formaldehyde, but in a molecular form that does not allow it to out-gas. The structural OSB in our panels is made exclusively with phenolic and urethane glues, and do not pose any known health hazards.
IS EPS FOAM A FIRE HAZARD?
We use modified EPS which contains flame retardant additives that retards its burning characteristics as compared to the EPS variety we are familiar with in our disposable cups and packaging materials. EPS products will progressively distort, soften, and melt when exposed to temperatures in excess of 175� F. As exposure temperatures continue to increase, combustible gases given off by molten residue will ignite in the presence of an ignition source. This temperature level, referred to as the flash ignition point, is approximately 700� F for modified EPS. This value may be directly compared to flash ignition temperatures for white pine and Douglas fir which is 500� F.
Unlike wood however, EPS makes a very small fuel contribution because it contains only about 3% combustible material by volume.
IN CASE OF FIRE, DOES EPS FOAM GIVE OFF TOXIC GASES?
When EPS bums, it produces smoke consisting mainly of carbon particles (soot). The only potentially toxic product of EPS combustion is carbon monoxide (CO). The concentration of CO is considerably less than that given off by equal volumes of wood and other common substances.
HOW ARE SIPS PANELS INSTALLED?
Each panel is designed for a specific wall or roof location per the supplied shop drawings. Installers use construction adhesive, nails and screws to permanently secure each panel in place.
HOW MUCH DO THE PANELS WEIGH?
Weight varies with the panel thickness and sheathing configuration. Our most widely used wall panel is 4 1/2" thick and weighs approximately 4 lbs. per square foot.
WILL XTREME CBS INSTALL PANELS FOR ME?
Yes, XTREME CBS offers this service as part of our package to the homeowner or contractor. We have trained crews and supervisors who travel throughout Louisiana, installing our SIPS for homes and commercial buildings. We also offer as an option, one senior installer on site to assist your crew.
HOW DOES A SIPS HOUSE COMPARE IN COST TO A CONVENTIONALLY BUILT HOUSE?
If you compare the cost of building two equal structures - one using conventional methods and one using SIPS - the difference in the price will be a negligible amount. However, the structure built with SIPS will provide a higher quality structure and the cost of maintaining a comfortable interior temperature (utility cost) will provide very significant savings for years to come.
Remember that the panel envelope accounts for only a fraction of the cost of construction, and that the degree and quality of finish materials determine the majority of the cost. With all these factors in mind, it is safe to say that if conventional methods are used to build a home that is insulated to the same degree as a SIPS home there will be little cost difference. We would add that while there is a small initial cost difference, there is a significant difference in value.
CAN SIPS HOMES INCORPORATE PASSIVE SOLAR DESIGN?
Certainly. However, passive solar design is a deceptively simple concept. In its simplest form, it is the application of certain techniques to collect and store the sun's heat in order to reduce the demands for purchased energy to heat and cool a building. In its simplest application. passive solar design techniques appear as wedge-shaped walls of glass an the south elevation that in theory collect free energy from the sun and keep the occupants warm all winter long. The more glass, the more heat.
SIPS construction can greatly simplify an energy efficient design due to the outstanding thermal efficiency of the structural envelope. Simple passive solar design principals can have a great impact. If the site or lifestyle of the occupants does not lend itself to solar design, the home can still perform extremely well due to its extremely small relative heat loss.
DOES PASSIVE SOLAR DESIGN THEORY CHANGE FOR SUPER-INSULATED HOUSES?
Passive solar design theory (and practice) does change when it is incorporated into a super-insulated building such as SIPS. Because of the extremely low heat loss of these structures, there is rarely a need for a vast expanse of glass on the south wall. However, all houses have windows for lighting, views, ventilation and egress, and these windows, unless shaded, will transmit some heat from sunshine. In a super-insulated house, the windows are the passive solar collectors, and the sizing and placement of the windows make up the passive solar design.
DO SIPS HOMES REQUIRE SPECIAL FOUNDATIONS?
No. They can be built on block, slab, piling or treated wood foundations.
WHAT ABOUT INTERIOR WALLS?
Interior walls are built using wood or metal studs in the conventional manner.
HOW ARE WINDOWS AND DOORS INSTALLED IN FOAM CORE PANELS?
Openings for windows and doors are cut and framed in the manufacturing process at the plant. They are located per the approved drawings.
WHAT KIND OF EXTERIOR FINISHES CAN BE USED?
Almost any kind of exterior finish can be used. The OSB or MgO laminated skin of the panel provides a sound nailing base for attaching conventional wood or vinyl siding. With the addition of a brick ledge to the foundation, the exterior walls can be finished with brick and/or stone. Stucco products are being used extensively on SIPS homes throughout the United States.
WHAT KIND OF ROOFING CAN I USE?
SIPS homes require no special roofing materials. Fiberglass, asphalt, wood, clay tile, concrete and metal are all suitable, but check the manufacturer's warranty before you buy fiberglass or asphalt shingles. Some shingle manufacturers have been hesitant about warranting their products when applied to unvented roof systems, claiming that unvented roofs could produce high shingle temperatures and thereby reduce shingle life. However, recent studies at the University of Illinois and Florida Solar Energy Center concluded that roof ventilation has little or no effect on shingle or sheathing temperature (Energy Design Update, Nov. 1990).
HOW IS ELECTRICAL WIRING INSTALLED IN FOAM CORE WALLS?
Wiring a foam core wall is not difficult, but does require planning. Although much of the wiring will be run in the conventionally-framed interior walls, there will certainly be some wiring in the panelized exterior walls. Our wall panels are manufactured with a wire chase at 18", and 54" above the floor. When we develop your shop drawings we locate and cut openings in the walls for outlets and switch locations. Our shop drawings also show wire chases in the ceiling and location of light or fan outlets.
WHAT ABOUT PLUMBING?
As with any construction, outside walls or the shell of a house has some plumbing requirements. In developing our shop drawings we identify the areas that have vents or water pipes for fixtures and outdoor faucets and accommodate them in the panel design. Our installation crew addresses these needs during the installation of the panel system.
WHAT KIND OF HEATING SYSTEM CAN I USE?
SIPS homes require no special type of heating system. Forced-air, electric, solar, radiant and wood-burning systems are all suitable, though some are more appropriate than others for a specific home design. Keep in mind that central air conditioning requires ductwork and is therefore most compatible with forced-air heating systems. Because of the home's tight construction, the fireplaces, wood burners, furnaces and any other combustion appliances should be provided with an outside source of combustion air. No matter what type of system you choose, the home's inherent energy efficiency means you will not need as big a unit as you would with a typical conventionally-framed building of equal size. Larger is not better. In our expenence, a SIPS home requires a HVAC unit about 50% of the size required by a conventionaly built home.
DO I NEED TO MAKE SPECIAL PROVISIONS FOR VENTILATION?
Yes. A properly constructed SIPS home has a very low air infiltration rate. That's great for reducing heating and cooling costs, but it isn't always healthy for the home or its occupants. We strongly recommend that a whole-house ventilation system be installed at the time of construction, and certainly before the first heating season. New homes are filled with new materials, and many of those materials, whether construction products, furnishings or finishes, will out-gas various pollutants. Emissions will decrease with time - many products are stabilized within six months of manufacture - but extra ventilation may be needed in the meantime.
There are several types of ventilation systems that can correct these problems effectively and efficiently. Some are exhaust-only units; others incorporate heat recovery devices. Some are self-ducted and others connect to forced-air heating systems. Your heating contractor should be able to help you choose and install the right system for your home.