Myths, Obstacles and Opportunities of Energy

Efficiency in the Re-Use of Historic Buildings

Sean DennistonNew Buildings Institute

Project Analyst

National non-profit & think-tank working to improve the energy efficiency of commercial buildings.

Intro

The Goal

We don’t have time to give you a comprehensive guide to energy

efficiency in historic preservation, but we can give you a framework and point

you in the right direction.

Intro

Myths

Myth # 1:

All old buildings are inherently inefficient.

Myths

Myths

The Hidden Barn, Vancouver, WAThe Home of NBI

Myths

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"The Barn" Certified Silver Gold Platinum

• NBI Study of the measured performance of 100 LEED buildings.

Myth # 2:

You have to replace those historic windows if you

want to be energy efficient.

Myths

Myths

Window Description U-Value R-Value

Loose: single glazed, no storm window 0.92 1.09

Double-glazed insulating wood sash, 1 over 1 0.49 2.04Double-glazed insulating vinyl sash & frame, 1 over 1 0.47 2.13

MythsWindow Description U-Value R-Value

Loose: single glazed, no storm window 0.92 1.09

Typical and tight: single-glazed, storm windows 0.51 1.96Single-glazed prime sash with low-e storm window 0.43 2.33

Double-glazed insulating wood sash, 1 over 1 0.49 2.04Double-glazed insulating vinyl sash & frame, 1 over 1 0.47 2.13

Myths

Yearly energy saving (on one 3’ x 5’ window): 625,922 BtuAnnual savings per window ( $0.95/therm): $9.65/ year_____________________________________________________Simple payback ($400 installed / $9.65 ): 41½ years!!

“OLD” WOOD WINDOW/REPLACEMENT WINDOW ENERGY ANALYSIS. -- Keith Haberern

Obstacles

IgnoranceObstacles

Ignorance

Obstacles

Ignorance

Obstacles MinimumBottom 35%Top 35%Maximum

Ignorance

• Mechanical Contractors are trained to minimize comfort complaints, not energy.

Obstacles

Ignorance

• Mechanical Contractors are trained to minimize comfort complaints, not energy.

• Many contractors and mechanical engineers don’t understand the latest techniques and approaches.

Obstacles

Ignorance

• Mechanical Contractors are trained to minimize comfort complaints, not energy.

• Many contractors and mechanical engineers don’t understand the latest techniques and approaches.

• Many consultants and mechanical engineers only understand how we build buildings now.

Obstacles

Obstacles The Code

The Code

• A building that meets code is not an efficient building.

Obstacles

The Code

Obstacles

The Code

• A building that meets code is not an efficient building.

• Code compliance can result in minimally efficient in-efficiency.Obstacles

Opportunities

Passive Strategies

Opportunities

Passive Strategies

1887: The cutting edge of Green Design.

Opportunities

Passive Strategies

1887: The cutting edge of Green Design.

Opportunities

Passive Strategies

• Minimized Glazing Area• Thermal Mass• Daylighting• Natural Ventilation

Opportunities

CommissioningOpportunities

ActualProposed

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asel

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These buildings appear to usemore energy than the code baseline!

Opportunities

Commissioning

Embodied Energy

Opportunities

Opportunities

Embodied Energy

Opportunities

Embodied Energy

Opportunities

Embodied Energy

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Baseline Getting to 50 Getting to 75 Getting to 0

Operational

Embodied

Major Lessons

Major Lessons

• Many historic buildings were designed for energy efficiency, take advantage of it.

Major Lessons

• Many historic buildings were designed for energy efficiency, take advantage of it.

• Commissioning is vital.

Major Lessons

• Many historic buildings were designed for energy efficiency, take advantage of it.

• Commissioning is vital.• Expertise! Expertise! Expertise!

Thank youNew Buildings Institute

Sean Dennistonsean@newbuildings.org

www.newbuildings.orgwww.advancedbuildings.net

www.gettingto50.net