Let’s look into these foam board insulation R value:
| Type | R Value |
| Polyurethane | 4 to 6.5 per inch of thickness |
| Polyisocyanurate (ISO) | 7.0 to 8.0 per inch of thickness |
| Extruded polystyrene foam (XPS) | 4.5 to 5.0 per inch of thickness |
| Expanded polystyrene foam (EPS) | 3.6 to 4.0 per inch of thickness |
Full Answer
What is the best insulation are value?
The best R-Value insulation for a colder climate will be at least R-29 for an attic or loft and around R-16 for a floor. Choosing the right kind of insulation to suit the climate where you live will make all the difference when it comes to enjoying a warmer living environment and the benefit of lower energy bills.
Which insulation has the highest R-value?
Types of Insulation
- Rigid Foam or Panel Insulation. The type of insulation with the highest R-Values, with a few exceptions, is rigid foam or panel insulation.
- Foamed-in-Place. Also called “spray foam,” foamed in place is the newest type of insulation used in residences. ...
- Blanket: Batts and Rolls. ...
- Loose Fill. ...
- Structural Materials. ...
What is the best insulation foam board?
What is rigid foam insulation made from?
- Polyisocyanurate. Polyisocyanurate, or Polyiso (PIR), is a foam used as insulation. ...
- Expanded polystyrene. You may already be familiar with this type of rigid foam without even knowing! ...
- Extruded polystyrene. Extruded polystyrene or XPS comes in blue or pink rigid board form and has an R-value of 5 per inch, making it denser than expanded polystyrene.
What does a higher are value mean?
What To Know When You’re Buying Home Insulation
- Insulation Can Save You Money. Heat travels. ...
- Buying Insulation. The first thing to look for when you buy insulation is the R-value. ...
- R-value Labeling. ...
- The Right R-value for Your Home. ...
- Report Problems. ...
Does foam board have an R-value?
Foam board insulation R-value varies based on type but is anywhere from 3.6 per inch of insulation thickness to 8.0. The types of foam board insulation include polyurethane, polyisocyanurate, extruded polystyrene foam, and expanded polystyrene foam.
What is the R-value of rigid foam?
Extruded polystyrene: Extruded polystyrene (XPS) rigid foam is usually blue or pink in color, with a smooth plastic surface. XPS panels typically aren't faced with other material. The R-value is about R-5.
What is the R-value of 1/2 foam board?
STYROFOAM extruded polystyrene insulation is rated at an R-value of 5.0 per inch at 75°F.
What is the R-value of 2 inch foam board?
With an R-value of 13.1 for a 2" thick sheet only two 2" sheets are required to achieve R-25. 2. Extruded polystyrene or XPS (foam is usually pink or blue) XPS has an R-value of 5 per inch of thickness requiring 5" of insulation to achieve R-25.
What is the R-value of 3 inch foam board?
R-Value Chart for EnerfoilTM Rigid Foam Faced InsulationThickness (Inches)R-value (in I-P/Imperial)RSI (R-value in Metric)2.012.42.162.515.52.73.018.63.243.521.73.786 more rows•Dec 13, 2018
What is the R-value of 1.5 inch foam board?
R 7.5Additional InformationThickness1.5 inLength8 ftWidth4 ftEdge TypeSquareR ValueR 7.53 more rows
Is foam board a good insulator?
Foam board insulation provides good thermal resistance and reduce heat conduction through structural elements, such as wood and steel studs, according to the U.S. DOE.
What is the difference between pink and blue foam board?
Both are manufactured using the same process and contain similar chemical components. The two products also have the same insulating power. However, blue foam boards are manufactured by Dow Chemical Co. whereas the pink foam boards are manufactured by Owens Corning company.
What is the R-value of Foamular 250?
Owens Corning FOAMULAR 250 Extruded Polystyrene (XPS) Insulation is a closed-cell, moisture-resistant rigid foam board well suited to meet the needs for a wide variety of building applications....Owens Corning FOAMULAR 250 XPS Insulation Board - All Sizes.ThicknessSq Ft Per BoardR-Value4"32 Sq FtR206 more rows
What is the R-value of Dow blue board?
DuPont™ STYROFOAM™ Scoreboard Insulation Board (Blue Board) 4 ft by 8 ft Sheet, 1" Thick, R value 5.0 A nonstructural, rigid board insulation manufactured of Extruded Polystyrene Foam (XPS).
Does foam board insulation need a vapor barrier?
Foam insulation usually does not require a vapor barrier. For some foam insulation types, such as closed-cell spray foam and foam board insulation, the insulation itself stops the movement of most water vapor.
What is the R-value of XPS insulation?
XPS Data Summary: R-value: 4.7 per inch.
Types of Foam Board Insulation & R Values
Foam board is commonly available in three variations, namely polystyrene, polyisocyanurate, and polyurethane. Let us have a brief look over their main characteristics, applications, and R-values.
Recommended R-value for Foam Board
If you’ve decided to insulate a building with foam board insulation, you’re probably curious about which rating to opt for. Here’s the thing: the recommended R-value for every area is different. The US is subcategorized into climate zones with each zone having its own R-value requirements for homeowners to follow.
Comparing Foam Board to Other Insulation Materials
Foam board insulation has its own pros and cons, but how well does it put up in competition with other popular insulation options such as fiberglass, rockwool, and spray foam?
Effect of Moisture on Foam Board R value
All products of foam board insulation come with special moisture-resisting abilities. For an insulation material, this can do wonders. Foam board insulation is almost completely impermeable. Due to this advantage, it is free from the need for a vapor barrier which is an additional cost.
Does compression affect R-value?
Compression can become a major issue during the installing process for insulation. In general, you’re not supposed to compress the material because doing so can negatively impact the R-value you’re trying to aim for. Foam board insulation cannot and should not be compressed. Hence, its R-value remains unaffected during the installation process.
Why Do R-values Differ in Foam Board Products?
You’re probably wondering how a single insulation material has different R-values. The answer to this question is quite simple. Since foam board comes in different variations with different compositions, each product has its own effectiveness in preventing heat energy loss. For instance, expanded polystyrene has a lower density and lighter mass.
Where to Use Foam Board Insulation
Deciding whether foam board insulation is right for you or not is an important decision. Foam board insulation is great at combatting moisture. Polyurethane, in particular, holds excellent moisture-resistant qualities that make it one of the best options for insulating areas where moisture would build up or pipe leaks might happen.
Foam Board Insulation R-Value Chart
R-value tells how well a foam board insulation can hold conditioned air. Be it heat or cool air. In technical terms, R value is the measure of resistance to the flow of heat.
Foam Board Insulation Types
There are basic three foam board insulation types. In the market, you’ll find only these 3 insulation foam boards under different manufacturer names.
How to choose the right type of rigid foam for your needs?
You can buy foam insulation at the local home depot. But, how do you choose most-right foam board insulation for your house? Here we get you through the buying guide in the next few minutes.
What rigid insulation has the highest R-value per inch?
Polyisocyanurate (Polyiso/ISO) rigid insulation has the highest R value per inch. It approximately ranges between 6.5 to 6.8. Also, generally, R values of rigid insulation are high. It generally has a foil facing on one side. While insulating the home one side, it adds a finished appearance to the place as well.
Final Thoughts
Foam board insulation are clever ways to insulate your home externally and internally! It truly does a great job. Though there are several foam board insulation types, choose one that fits in your needs & budget.
What is the most expensive foam board insulation?
Cost = Polyiso is the most expensive of the foam board insulation products however it’s the highest R value. Polyurethane and polyisocyanurate are both closed-cell foams. They contain low-conductivity gases in the cells (usually one of the HCFC or CFC gases.) The higher R-Values (R 7.0 to 8.0) are the result of thermal resistance ...
What is the R value of polyisocyanurate?
Polyiso is typically used with a foil facing and it has an R value of 7.0 to 8.0 per inch of thickness.
What is EPS foam?
Expanded polystyrene foam (EPS) is the cheapest and least used foam board product on the market. This product typically has an R value of 3.6 to 4.0 per inch of thickness. Expanded polystyrene insulation is similar to the foam used for packing “peanuts” and it’s typically used for insulated concrete forms also knows as ICF’s. It is also sometimes used on commercial buildings for roof and wall panel insulation which is typically sandwiched between light gauge metal.
Is 6" of fiberglass insulation needed?
In most areas there are minimum required insulation values for cathedral ceilings and attics. 6″ of fiberglass even with 2″ foam won’t likely get enough r value. Sistering a 2×10 will only make the roof stronger, not weaker, and that will get you closer.
What is R value?
R-values are a key metric used to assess insulation products. But what exactly do they measure? And why are they important? In this post, we’ll find out what R-values are, why they’re crucial to the homes we build, and how various insulation products compare in R-values. YouTube.
How are R values measured?
How are R-values Measured? To get a fair comparison between different foam board insulation (FBI) products, the initial R-value is measured at the time of production, with a standard temperature of 75°F. That said, some FBI panels keep more of their R-values as time goes on, and fare better in extreme temperatures, than others.
How hot should polyiso boards be?
Polyiso offers solid initial R-values of R-5.6 to R-6 per inch. But there’s a catch: you’ve got to keep these boards warm, preferably above 50°F if you don’t want them to lose these R-values. Unlike most rigid foam boards, they ironically lose their thermal resistance as temperatures fall.
What is the flaw in polyiso insulation?
The other flaw of polyiso is that its R-values diminish over time. Similar to XPS, polyiso is known to lose 10% of its R-value in the first 5 years of service. Impermeable just like XPS, polyiso should not be used as continuous exterior insulation when the interior has a vapor barrier.
What is GPS board made of?
GPS boards are made of expanded polystyrene foam (EPS) that is infused with graphite particles. The graphite in these foam boards reflects radiant heat, complementing the foam air bubbles’ ability to block conductive heat. This unique function gives them a relatively high initial R-value of 4.7 per inch.
What does higher R mean?
Higher R-values mean less heat loss, more comfort, and a reduced load on heating and cooling systems. As you’ve seen, different rigid insulation products have distinct R-values, and not all of these last as time goes by.
Can XPS boards be used as continuous insulation?
Because of this drawback, XPS boards should not be used as exterior continuous insulation where there’s a vapor barrier on the interior. Such a composition could cause the “double vapor barrier effect”, where a minor imperfection can lead to moisture build-up inside the wall cavity.
Table of Characteristics of Various Insulating Materials
These tables give R-values of all sorts of materials, in alphabetical order with direct links to some popular insulating materials; give the insulating value of any material of interest in constrution, for example: air, fiberglass, masonry mateirals, mineral wool, cellulose, foam insulating board, UFFI, soil or dirt, vermiculite, wood, & most other building materials..
Complete Table of Insulation & Other Building Material Properties - Alphabetical Order
The R=0.87 value for the first value in this Air R-value table subsection: -does not consider internal convection effects. -does not consider presence / absence of reflective barriers. -does not consider directions of heat flow up or down nor winter/summer conditions. Also note that there are differences for inside vs outside air films. For all of these air space R-values also see Masonry citations below..
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About This R-Value Table
The following table provides typical R-values (and RSI) for various materials.
Check with the Manufacturer
When calculating the R-value for a real-life installation, always refer to the manufacturer’s data sheets for the actual, specific product you intend to use, or contact the technical department of the product manufacturer or material provider.
R-Value vs. RSI
R-value is used in the United States. RSI (R-value Système International ) is the metric equivalent.
R-Value and Energy Codes
Please note that the R-values for roof membranes, shingles, tiles, air films, and roof deck materials will probably not be permitted by your local code to be included when total roof assembly R-value is being calculated for the purpose of satisfying energy code requirements.
R-Value Chart
Note: While the R-Value for a material is typically given per inch, the RSI is typically given per millimeter, so please be aware that the R-Values and RSI values for the materials in the following table are not for equivalent thicknesses.
