Sustainable Design What’s the Bottom Line? - usgbc.org€¦ · Sustainable Design What’s the Bottom Line? Presented by: Tom Pientka, President & Owner Ken Pientka, Chief Operating

Sustainable Design What’s the Bottom Line?

Presented by: Tom Pientka, President & OwnerKen Pientka, Chief Operating Officer

PLANNING Design Build, Inc.Madison, Wisconsin

Today’s Presentation

Objectives• Compare and evaluate the first cost differences between two

nearly identical office buildings. The first being a well designed energy efficient office building and the second office building designed to achieve Gold certification under USGBC’s LEED™Program – we will call this the Concept Building.

• Understand the cost differences on several of the main building systems.

PLANNING’S Motives

• Recognition that sustainable design is the coming trend.

• PLANNING had limited knowledge in sustainable design topics & LEED™

• Our research indicated that there was limited hard data about actual cost premiums for sustainable buildings.

PLANNING Design Build, Inc.Company Overview

• A design-led, design-build general contractor consisting of Architects, Engineers, Interior Designers, Estimators, Field Superintendents, Project Management and Quality Control.

• Our company structure uniquely qualifies us to design holistically . . . a key element for successful sustainable design.

Tomotherapy vs. Concept Building

TomoTherapy Headquarters

Concept Building

TomoTherapy

TomoTherapy is a medical technology company that has developed a revolutionary method to deliver radiation treatment for cancer.

The TomoTherapy Hi·Art System delivers radiotherapy which conforms to the size, shape, and location of the patient's tumor, minimizing damage to healthy tissue surrounding the tumor.

Site Plan

Building Comparison OverviewTomoTherapy Headquarters

Concept Building

Size (sq. ft) 66,206 54,687

Schedule Construction Completed June, 2002

Competitively Bid January, 2003

LEED Scoring 11 points / 26 points 45 points (Gold)

HVAC System Overhead VAV52% energy savings vs. 90.1

Raised Floor54% energy cost savings vs. 90.1

Storm Water Management Modest use of low islands, overland swale and roof garden

Maximized use of free green area on site to control runoff and 75% green roof

Building Comparison Overview (cont.)TomoTherapy Headquarters

Concept Building

Glazing High performance glass optimally selected for each orientation

High performance glass optimally selected for each orientation

Lighting 1.5 w/sf – Indirect T5 HO lighting with dimming ballasts and std. Efficiency fixtures (88% efficiency)

.75 w/sf Indirect, t5 HO lighting with dimming ballasts and high efficiency fixtures (93.8%)

Materials and Resources Modest use of recycled and renewable materials

Maximized use of locally sourced rapidly renewable materials and high recycled content

Water Use Met the 1992 Energy Policy Act guidelines

Reduce base building water use by 20% vs. 1992 Energy Policy Act guidelines

Concept Building Process

• Overall Goal – To create a ‘twin’ sustainable building using holistic design principles.

• Formed an interdisciplinary team of designers, construction staff, specialty consultants, contractors and suppliers.

• Developed committees that mirrored LEED™ categories

Project Costs

• TomoTherapy – Designed and built during the period of 10/01 through 6/02. Project costs based on total actual costs and include DB contractor fees and profit.

• Concept Building – Fully developed drawings. Project was competitively bid by subcontractors in January 2003.

• Project costs for TomoTherapy were adjusted to normalize costs with Concept Building and to remove variables such as changes in building codes and site conditions

• Concept Building includes commissioning costs.

• No cost adjustments for inflation.

LEEDTM ScorecardTomoTherapy TomoTherapy

Certified Concept Building

Sustainable Site 4 4 11

Water Efficiency 0 3 4

Energy & Atmosphere 5 9 12

Materials & Resources

2 3 5

IEQ 0 6 13

Innovation & Design Process

0 1 0

Total 11 26 45

Overall Cost Comparison

$103.30$ 83.81

$93.20$91.75$ 73.91

Cost/SF (Total) (Shell)

$5,649,000$ 5,100,000$ 5,018,000Total Cost (Shell & Buildout)

Concept BuildingTomoTherapy Certified

TomoTherapy

Sustainable SitesObjective: Minimize storm water impacts – Retain all storm water on site for a 20 year storm event.

$ 231,900TOTAL$ 111,600TOTAL

$ 129,000($9.36/sf of roof area)

Green Roof$ 53,000Ballasted Rubber Membrane Roof

$ 37,000Rain Gardens$ 5,000Turf Grass

$ 13,900Pervious Paving substituted for Asphalt in loading dock (2200 sf)

$ 2,600Asphalt Paving

$ 52,000StormCeptorUnderground CisternDepressed Parking Islands

$ 51,000Storm Sewer Piping

CostTechniqueCostTechnique

Concept BuildingTomoTherapy

Sustainable SitesGreen Roof

$ 129,000($9.36 / roof sf)

$ 53,000TOTALS

$ 7,500Additional Roof Steel

$ 39,000Roof & soil vegetation (6’ depth)

$ 82,500Torch applied modified bitumen roof system

$ 53,000Rubber Roof System

Concept BuildingTomotherapy

Roof Rain Garden Analysis

• Minimal cooling load impact• Roof rain garden cost/sf on low end of published data• Consider elimination of roof garden as other storm water management measures are in place.

Roof garden not cost justified on a Life Cycle Cost basis.

Materials & Resources

$ 20,000 Less$ 56,680$1.04/sf

$ 76,000$ 1.39/sf

Foundations & Footings Concrete

$ 81,000 Less$ 6.44$ 7.92 Total Framing Cost/sf

Additional dead load from green roof had minimal cost impact. More economical bay size resulted in lower total costs.

Steel JoistsSteel JoistsRoof System

Plank has limited economical spans in comparison to joists. - Joist system has less dead load- Concrete used in concept building deck contains recycled fly ash

Steel joists w/metal decking and concrete topping

Precast Plank w/concrete topping

Floor System

Larger bay sizes in Concept Bldg. w/joist floor system – fewer columns

Structural SteelStructural SteelBuilding Frame

CommentConcept BuildingTomoTherapy

Framing System

Materials & ResourcesRecycled & Recyclable Materials

• Bar joist framing & concrete deck – Cost savings vs. precastand increase in recycled materials

• Changed specifications to require use of fly ash & blast furnaceslag – no cost increase

• 100% recycled gypsum wall board – no cost increase

Materials & ResourcesRecycled & Recyclable Materials (Continued)

• Used recycled acoustical tile (70% recycled paper) – no cost increase, most tile is recycled.

• Recycled ceramic tile – big cost premium (approximately 2X) – did not use

• Cotton insulation not available to substitute for fiberglass

• Used carpet with 31% recycled content - No cost increase

Materials & ResourcesRapidly Renewable Material

• Used bamboo to replace cherry flooring. Bamboo saves 60% vs. Cherry.

• Used Cork Flooring ($11.55/sf) in lieu of VCT ($1.50/sf). ($9,000 premium)

Energy & AtmosphereLow Emitting Materials

• Adhesives & Sealants – specified LEED™ criteria

• Paintings & Coatings – selected products with zero VOCs (no cost increase)

• Carpeting – met Carpet & Rug Institute guidelines while maintaining recycled & recyclable goals. Used carpet tiles throughout – raised floor.

• Composite Woods – specified formaldehyde-free MDF for cabinets & case work.

Energy & Atmosphere

• Optimized design by integrating glazing selections, 10’ ceiling heights, window placement, office layout and fixture selection

• Used indirect lighting system with T5 high output lamps, high efficiency fixtures (93.8%), daylight sensors and dimming ballasts

• Fixtures mounted 3’ below ceiling 20’ on center

Lighting

Energy & AtmosphereLighting (Continued)

• Lighting load of .5W/sf in open areas and .75w/sf overall– Tomotherapy – 1.5w/sf– Reduced cooling load by 12 tons

• Site lighting – 1242 w/acre (.03w/sf) $ 25,000 premium vs. TomoTherapy to achieve 20% load reduction. (not cost effective)

Energy & Atmosphere

• Raised floor distribution system

• Sealed combustion boiler (88%)

• Self-contained packaged units

– Scroll compressor .9 kw/ton

– VFD on air handler

• VFDs on cooling tower fans, hot water pumps & energy recovery unit.

• Tate Access Flooring System

• DDC Control System

HVAC

$ 386,000$ 362,000Electrical System

$ 88,000$ 54,000DDC Controls

$ 623,000$ 538,000HVAC System

Concept BuildingRaised Floor System

TomoTherapy IOverhead VAV w/Heat

Recovery

Difference = $143,000 ($2.60/sf)

Energy & AtmosphereHVAC

Energy & Atmosphere

• Peak cooling load of 100 tons (550 sf/ton)– Green Roof had minimal impact on peak load– Reduced cooling loads from building overhangs

• 1.8% for 2’ overhang • 5.2% for 4’ overhang.

• Purchasing a packaged unit ducted into floor saved a total of $48,000 vs. custom AHU, but cost 1 point due to use of HCFC. 60 sf/floor of rentable space would also be lost. (Annual value of $2,700/yr)

• Raised floor HVAC pricing includes humidifier. ($25,000)

• Electrical system cost premium driven by site lighting costs. Minimal impact from raised floor.

HVAC System Analysis

Energy & AtmosphereHVAC - Raised Floor System Costs Analysis

• HVAC System + $ 119,000

• Access Flooring System + $ 390,000– Carpet tiles sized to fit raised floor adds additional cost +/- $1/sf

• Total cost premium of $ 533K + carpet tiles must be offset by:– Increases in employee productivity– Reduced churn costs estimated at $ 1500/employee/year– Minimal energy savings

Design Adjustments

- 1 point$ - 404,000TOTAL

0+ $ 41,000True up for change in private office count

0+ $ 101,000Add back savings from change in building frame

0- $ 67,000Replace green roof with silver reflective roof

0+ $ 33,000Eliminate building height reduction savings by eliminating raised floor

- 1 point- $ 512,000Replace Raised Floor System w/Overhead VAV (Includes replacing access floor system)

LEED™ Scoring$ ChangeCost Adjustment

Cost Summary

• Original Cost Difference $ 631,000($ 5.649 M vs. $ 5.01 M)

• Cost Adjustments -$ 404,000(from previous slide)

Cost Increase to achieve $ 227,000

LEED™ Gold rating ($ 4.15 / sf)

After Design Adjustments

Conclusions

• A LEED™ Gold building can be constructed for about+/- $4.15/sf additional vs. the TomoTherapy building.

• Raised floor technology was new to our contractors (HVAC & Electrical) and may have affected pricing.

• Integrated / Holistic Design combined with access to accurate pricing is essential to optimize design yielding the best combination of performance, sustainability and cost.

• Time required for design burden to document and perform LEED™calculations is substantial and may be a barrier to applying forcertification.

• Sustainable buildings are affordable. It is the right thing to do. Our role as professionals is to make it happen!

Contact Information