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SmartWall Systems provides significant thermal savings. The savings will often completely pay for the block, if not more, over the life of the building. That why smart designers specify and use SmartWall Systems.

Wall Construction: Single wythe 8" CMU with polyurethane foam core insulation. Location: Omaha, NE Fall, 1999.
Density of Concrete Masonry Unit

Normal
Weight

135 lb/ft3

ASTM C 90 Lightweight

105 lb/ft3

SmartWall
Systems

90 lb/ft3

Wall Weight, lb/ft2
39.2 30.9 26.7
R Value
3.40 5.60 7.30
U Value
0.29

0.18

0.14
Compared to a 135 lb/ft3
Difference in U values
--- 0.12 0.16
Heating Energy Savings: $/sq ft/yr
$0.10 $0.13
Cooling Energy Savings: $/sq ft/yr
$0.01 $0.01
Present Worth over 10 year period: $/block
$0.84 $1.15
Present Worth over 30 year building life: $/block
$2.10 $2.86

See the following example calculation details.

Designing with SmartWall Systems can provide significant savings in heating and cooling. Even when used as backup in insulated cavity walls, the energy savings are still notable-. For more information on SmartWall energy savings in cavity walls, other types of block core insulation, or for other geographic locations, contact Buildex Inc. or your local SmartWall Systems block producer.

SmartWall has benefits for everyone involved in building construction — the Owner/Occupant, the Designer, the Masonry Contractor, the Block Producer, and their suppliers.

We at Buildex are proud and excited to be part of this program. We welcome the opportunity to visit with you about all the benefits of using SmartWall Systems.

 


Life Cycle Energy Cost Analysis Present Value of Annual Energy Cost Savings Using SmartWall Systems Over a Thirty Year Period

Wall construction: Single wythe 8" w/foamed in place core insulation
Location: Omaha, Nebraska

R Value Data

CMU Density

.

135 lb/ft3

105 lb/ft3

90 lb/ft3

R value (3)

3.40

5.60

7.30

Calc: U value
0.294
0.179
0.137

Calc: Difference in U values
(vs 135 lb/ft
3)

---

0.116

0.157

R-value in (hr • ft2 • ºF) / BTU. U value in BTU / (hr • ft2 • ºF)


The following analysis makes two comparisons. The left column compares lightweight units meeting ASTM C90 at 105 lb/ft
3 to ordinary 135 lb/ft3 units. The second comparison (in the right hand column) is between a SmartWall Systems unit at 90 lb/ft3 and the same 135 lb/ft3 unit. All units are conventional 8" x 8" x 16" size. The analysis Shows that SmartWall Systems units save substantial energy costs when compared to both ordinary 135 lb/ft units and regular ASTM C 90 lightweight units.

Heating Cost Calculations

ASTM Lightweight
105 lb / ft
3 CMU

SmartWall
90 lb / ft
3 CMU

U value difference vs. 135 lb / ft3 cmu (from above)
0.116
0.157
Natural Gas Cost (2) per mcf

$4.53

$4.53

Furnace efficiency

0.80

0.80
Calc: $ Cost per Btu output

5.66E — 06

5.66E — 06

Heating Degree Days for This Location (1)

6201

6201

Calc: Energy Savings: $ / sq ft / yr

$0.0974

$0.1324

Calc: Energy Savings: $ / block / yr
$0.0866
$0.1177
Present Worth of Heating Savings n (years)
30
30
i (nominal rate — energy and money)(4)
2.00%
2.00%

Calc: Present Worth of Heating Energy Savings, $ / block

$1.94

$2.64


Cooling Cost Calculations

.

.

Electricity Cost (2) per kwh

$0.0538
$0.0538
SEER
10
10
Cooling Degree Hours for This Location (1)

13180

13180

Calc: Energy Savings: $ / sq ft / yr

$0.0082

$0.0111

Calc: Energy Savings: $ / block / yr
$0.0073

$0.0099

Present Worth of Cooling Savings n (years)
30
30
i (nominal rate — energy and money) (4)
2.00%
2.00%

Calc: Present Worth of Cooling Energy Savings, $ / block

$0.16

$0.22


Calc: Present Worth of Total Energy Savings, $ / block

$2.10

$2.86

See ESCSI Information Sheet No. 3530 for references and information on energy savings in other major US cities. Wall weights are from Concrete Masonry Design Tables, TR-121, Table 7.2, National Concrete Masonry Association, 1993.