Technical Report. Prepared For: JEP Management, LLC Attention: Mr. John Propst 3219 East Camelback Road #524 Phoenix, AZ 85018

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1 NVLAP Lab Code Technical Report Estimated Heating/Cooling Envelope Loads in Selected Cities for a Building Using Continuous Insulation Panels Produced by JEP Management Prepared For: JEP Management, LLC Attention: Mr. John Propst 3219 East Camelback Road #524 Phoenix, AZ R & D Services, Inc. P.O. Box 2400 Cookeville, Tennessee Report: RD13529 David W. Yarbrough, PhD, PE August 27, 2013 The test results in this report apply only to the specimens tested. The tests conform to the respective test methods except for the report requirements. The report includes summary data but a full complement of data is available upon request. This report shall not be reproduced, except in full, without written approval of R & D Services, Inc. This report must not be used by the Client to claim product endorsement by R & D Services, Inc., NVLAP, NIST or any other agency of the U.S. Government.

2 Estimated Heating/Cooling Envelope Loads in Selected Cities for a Building Using Continuous Insulation Panels Produced by JEP Management Background The building component concept that uses specially coated seven-inch thick polystyrene board stock to construct continuous insulation wall panels is extended to include roof panels in this report. Roof panels with an eleven-inch thickness of polystyrene with an embedded 3 by 6 inch structural element in each four-foot wide panel are specified for the construction of 1200 ft 2 residences initially intended for use in Arizona. This report contains estimates of the cooling and heating loads resulting from heat transfer across the building envelope for twelve cities across the US. Basis for the Calculated Loads The load for a structure includes several factors: heat gain or loss across the envelope, conditioning of incoming air, heat gain or loss from the ground below the structure, and internally generated heat. The present calculation deals only with the heat gain or loss across the building envelope (walls, doors, roof, and windows). This component is directly related to the thermal properties of the walls, roof, windows, and doors. Description of the Residential Unit A 30 by 40 ft. single level structure was selected for this estimate. The walls are made using JEP wall panels with seven-inch thick polystyrene panels that are over 85% continuous insulation while the roof is constructed with eleven-inch thick polystyrene panels that is primarily continuous insulation. The roof will be built with a 4/12 pitch with no added thermal insulation below the roof panels. The important design parameters are listed in the following table. Table 1. Design Parameters for Model Residence Floor area 1200 ft 2 (120 m 2 ) Wall area 1120 ft 2 Window/door area 10% of wall area Opaque area 90% of wall area Wall R 20.5 to 33.9 ft 2 h F/Btu depending on the type of polystyrene used. Roof R 31.2 to 51.6 ft 2 h F/Btu depending on the type of polystyrene used. Window/door R 3 COP 3 for air conditioning or heat pumps Furnace efficiency 90% for fossil fuels Page 2 of 10

3 Climate Data City State CDD 65 HDD 70 San Jose CA Sacramento CA San Diego CA Phoenix AZ Houston TX Austin TX Las Vegas NV Orlando FL Atlanta GA Miami FL St. Louis MO Mobile AL Climatography of the United States No. 81-Supplement No. 2 Load Calculations Calculations of annual cooling load (Kwh per year) have been done using the total UA for the model residence. The factors included in the total UA are the opaque wall, windows, doors, and roof. This means that cooling loads from the ground and air exchange are not included. The total UA depends on the R* (R per inch of thickness) for the polystyrene that is used. Table 2 contains the UA terms for the three primary elements of the building envelope. The load due to the relatively low-r windows/doors is a major contribution to the total load. Table 2. UA Values by Component (90% Opaque Wall) R* UA (Btu/hr F) UA Roof Opaque Wall Window/ Door Total Summer Winter Summer Winter Summer Winter Summer Winter Table 3 contains the calculated annual Kwh required for an all electric unit as described above. Table 4 contains calculated cooling load in Kwh (for COP 3) and heating load in millions of BTUs (for furnace efficiency 90%). Page 3 of 10

4 Table 3. Calculated Kwh with COP 3 (all electric) City R* Winter Summer Total (Kwh/yr) San Jose Sacramento San Diego Phoenix Houston Austin Las Vegas Orlando Page 4 of 10

5 Table 3. Calculated Kwh with COP 3 (all electric) - continued City R* Winter Summer Total (Kwh/yr) Atlanta Miami St Louis Mobile Page 5 of 10

6 Table 4. Annual Loads with COP 3 (Summer) and Furnace Efficiency 90% (Winter) City R* Winter (MMBTU) Summer (Kwh) San Jose Sacramento San Diego Phoenix Houston Austin Las Vegas Orlando Page 6 of 10

7 Table 4. Annual Loads with COP 3 (Summer) and Furnace Efficiency 90% (Winter)- continued City R* Winter (MMBTU) Summer (Kwh) Atlanta Miami St. Louis Mobile The annual heating and cooling loads due to envelope have been estimated for the four cities listed in Table 1. The thermal load is converted to electrical load for an all-electric house using a coefficient of performance of the air conditioning equipment (heating and cooling) of 3 (SEER ~ 11). The annual loads are directly proportional to the weather parameters HDD and CDD which is listed in Table 1. The results for annual cost can be estimated by multiplying kwh/yr by $/Kwh. Figure 1 contains a bar graph showing Kwh/yr for all electric houses in the selected cities with walls and roof panels constructed with selected values of R-per-inch polystyrene with JP coating. The results in the graph indicate heating and cooling for the selected cities due to the heat flow across the envelope ranges from 400 to 1700 Kwh/yr as R* is increased from 3 to 5. Page 7 of 10

8 City Number All Electric Kwh/yr R*=3 R*=3.5 R*=4 R*=4.5 R*=5 Figure 1. Electrical Loads due to the Walls/ Windows, and Roof for All-Electric Heating and Cooling The annual cost of heating and cooling due to the heat loss or gain across the envelope is estimated from the loads contained in Tables 3 and 4 and the latest cost of electricity and natural gas published by the U.S. Energy Information Administration. The cost associated with 1.0 MMBtu is taken to be the cost of 1000 SCF of natural gas. Table 5 contains the factors that were used to estimate annual costs. Page 8 of 10

9 Table 5. Residential Energy Costs from EIA* City Electricity ($/kwh) Fossil ($/MMBtu) San Jose Sacramento San Diego Phoenix Houston Austin Los Vegas Orlando Atlanta Miami St. Louis Mobile * EIA data are listed by state. The utility cost factors in Table 5 are combined with the results in Tables 3 and 4 to estimate annual cost associated with heat transfer across the building envelope. The results are contained in Table 6. Table 6. Estimated Annual Costs for Heat Gain and Heat Loss Across the Envelope R/in =3 R/in =5 City All Electric Electric and Fossil All Electric Electric and Fossil $/yr $/yr $/yr $/yr San Jose Sacramento San Diego Phoenix Houston Austin Los Vegas Orlando Atlanta Miami St. Louis Mobile Page 9 of 10

10 Summary The results in this report indicate that the heating and cooling loads attributed to the model residence walls and roofs are very small. The annual loads have a strong dependence on the area and thermal resistance of the windows and doors since this part of the envelope has a small thermal resistance in comparison with the full-thickness panels of the walls and roof. The annual loads in Tables 3 and 4 and the estimated costs in Table 6 do not include internal load, heat gain from the ground, or load due to conditioning inlet air. These loads do not depend on the thermal performance of the envelope. Lighting, appliances, and occupants are not included. The structure under discussion is essentially air-tight. There is an opportunity for air-toair exchangers to reduce the cost of conditioning incoming air. The JP design is largely continuous insulation, a fact that is reflected in the large overall R-values and small U- values. David W. Yarbrough, PhD, PE August 27, 2013 Page 10 of 10