Compare Insulation R-Values


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Compare Insulation R-Values 

The main purpose of insulation in a home is to reduce or prevent heat flow.  Remembering that heat always goes to cold, heat flow, or transfer of heat, occurs when it's cold outside and the heat escapes from your home.  And when it's hot outside the heat comes inside.  Ultimately, the goal is to maintain a comfortable living environment while saving energy and ultimately money.

When comparing insulation R-values *, it's important to understand that not all insulations are alike.  Some wall and roof insulations are better at resisting heat flow than others.  Consequently they have a higher resistance value or "R-value".  The higher the R-value the better resistance and less insulation thickness is required to achieve the insulating effect you desire.  The chart below can help you compare some of the more common materials and approaches to insulating homes along with their corresponding R-values. 


 Compare Insulation R-Values to SIPs RAYCORE

With most types of insulation, as the temperature drops the R-value increases, but some perform much better than others.  It is important that, when you compare the R-values of different insulations, you know at what temperature the product was tested. In the US, the apples-to-apples R-value standard is ASTM C518, and the test results are reported a temperature of 75°F. In colder climates where your heating costs are high, you might be more interested in the insulation's R-value at maybe 60°F or 40°F or maybe even 20°F, but for this comparison chart, RAYCORE will use the ASTM C518 Standards at 75°F.


Comparing Insulation R-Values of RAYCORE SIPs  to Sandwich Panels

 Compare Insulation R-Values SIPs to RAYCORE Thickness

In the real world, most of us live where the average daily temperature is less than 75°F. Most insulations perform better, sometimes significantly better, as the temperature drops. For this reason, in the ASTM C518 testing process, insulation R-values are recorded at other temperatures.  This graph above shows insulation values of RAYCORE SIPs and Sandwich Panels at the more commonly reported real-world R-value of 40°F as will be found on most SIPs Panel manufacturers websites.


Does Panel Thickness Matter?


It does to RAYCORE and it should to you too! 

Cost & R-value - Most sandwich panel suppliers price their panels by thickness, not R-value.  Unless you specify to them a particular R-value, most likely you will be quoted for a 6 1/2" thick panel.  Most pre-prepared sandwich panel SIPs house plans will specify a 6 1/2 inch thick panel.  There are reasons this panel is most commonly specified and quoted.  Ultimately, it all comes down to cost.  RAYCORE's 5 1/2 inch panel is almost twice the R-value and could be half the price of the sandwich panel SIP.

Sandwich panels are competing with other insultations and types of panels.  These types of panels are generally 2 to 3 times more expensive than other insulations.  The thinner the panel, the lower the price.  A 6 1/2 inch thick EPS sandwich panel has an R-value of 24.  RAYCORE's 5 1/2 inch thick polyurethane SIP panel has an R-value of 42.  That's 75 percent more R-value for half the price!  To reach a similar R-value with a sandwich panel, you would have to purchase their 10 1/4 inch thick panel with an R-40 or their 12 1/4 inch thick thick panel with an R-48 insulation value.  If the 6 1/2 inch thick sandwich panel costs 2 to 3 times more, how many times more do their 10 1/4 inch or 12 1/4 inch thick panels cost to achieve a similar R-value?

Secondly, the thicker the panel, the greater the cost of almost every material associated with closing-in the outside walls and roof of the house.  These materials are not included in the sandwich panel package.  Thicker panels, mean larger framing materials for top and bottom wall plates, windows and doors framing, roof framing, fascia and more.   All sandwich panels result in a nonstandard wall thickness.  Your windows and doors will all need expensive window and door jamb extensions or special materials and labor to trim them out on-site.  The thicker the wall, the greater the cost. 

RAYCORE SIPs use standard framing materials, standard roof framing, facia and more.  Window and door jambs are standard, so never any added cost.


Other Costs You Might Not Have Thought Of:


  • Costly Engineering:  All sandwich panels require special and costly engineering. Whether you use the sandwich panel manufacturer's engineer or hire your own, this sometimes will add twice the cost to the package price.  RAYCORE Structural Insulated Panels are considered by code as standard framing.  No special and costly engineering is required to use RAYCORE SIPs. Simply have your plans prepared by your designer, builder, architect or engineer, or go online and purchase an affordable plan from one of the many architectural house plan sites.


  • Window and Door Cutouts:  Sandwich panel suppliers are always excited to tell you that they will do the window and door cutouts for you.  That may sound great, but you need to remember this isn't free.  First, whether you know it or not, you are purchasing their panels at a per-square-foot price.  You pay for that panel that they will cut out and throw away for you.  Secondly, they don't do the work for free. You will pay factory labor prices for the work to be done. And, what if they cut it wrong or you decide to make a change?  These panels are engineered.  You can't just fill the hole in and cut a new one in a different place.  If it is their fault, they will replace it for you, but if not, the cost is on you.  You will have to purchase a new panel, wait for it to be engineered, manufactured, and shipped all at a very high cost to you.  All this will be costing you time and money.  RAYCORE SIP Panels are modular, no ups, downs, rights or lefts. Window and door openings are cut out and framed onsite with affordable onsite labor.  And the panel material cut out... you will use the material elsewhere in the wall or roof assembly, reducing the cost of the SIPs and saving the waste.


  • Special Accessories and Tools:  A variety of special accessories and special tools are needed for installation which you may need to purchase from the supplier.  RAYCORE uses conventional framing practices, so no special tools or accessories are required.


  • Freight Expense:  Sandwich panels freight class is one of the highest and most costly rates. Very heavy, and usually shipped in larger sections, it could take twice or more the trucks to deliver sandwich panels. Twice the trucks, three times the price per pound...  RAYCORE panels are classed at a very affordable shipping rate, and because the panels are lightweight and can be efficiently loaded on a truck, RAYCORE shipping costs are minimal in comparison to sandwich panels.


  • Special Builders:  Do you want a warranty?  If the sandwich panel company offers a warranty (some don't), for it to be effective you must use one of their certified builders. Availability may not be good in your area.  Travel, housing and special labor rates all will add to the cost of your build.  RAYCORE insulated wall and insulated roof panels require no special or certified builders. Choose one you know and trust or contact the local builders association. Even do-it-yourself-ers can build with RAYCORE SIPs and if installed right, the structural insulated panels will remain structural and will last the life of your structure - we back this up with our lifetime warranty.


  • Onsite Crane for Installation:  Sandwich panels are heavy and often come in large sections, requiring several days of very expensive by-the-hour crane time.  RAYCORE panels are lightweight and easy to handle. No cranes are required.


 * R means resistance to heat flow. The higher the R-value, the greater the insulation power. See RAYCORE SIP Panel Specification Sheet or Fact Sheet



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