Here’s a curated list of online resources relevant to historic preservation, sustainability, Historic Home Performance, deep energy reductions, and historic windows. Note that this list is constantly evolving and expanding, so please feel free to post a comment at the bottom if there’s anything you feel ought to be included here.
The National Park Service publishes definitive guidelines for historic preservation in the United States. This includes the well known Secretary of the Interior’s Standards for the Treatment of Historic Properties, and the Secretary’s more recent Guidelines on Sustainability. Any one serious about improving the energy efficiency of historic properties ought to be well-versed in these guidelines, since they’re heavily relied upon by federal agencies, local and state preservation offices, historic commissions, and even local building departments, in deciding what modifications may, or may not, be allowed on certain historic buildings. Here are links to key web pages and publications:
National Park Service, Technical Preservation Services: Home page.
National Park Service, Technical Preservation Services: Secretary of the Interior’s Standards for the Treatment of Historic Properties, With Guidelines for Preserving, Rehabilitating, Restoring, and Reconstructing Historic Buildings.
National Park Service, Technical Preservation Services: Sustainability.
National Park Service, Technical Preservation Services: Illustrated Guidelines on Sustainability for Rehabilitating Historic Buildings (PDF).
National Park Service, Technical Preservation Services: Preservation Brief #3: Conserving Energy in Historic Buildings.
The concept of embodied energy often is used to justify preserving and rehabilitating existing buildings, rather than demolishing and replacing them with new, supposedly “greener”, buildings. Research conducted in the 1970s produced several detailed models of embodied energy in the built environment, one of which is realized by the calculator below. The two articles listed revisit the topic of embodied energy, the former from the perspective of preservation and the early embodied energy models, the latter from the viewpoint of green building.
The Greenest Building .org: Embodied Energy Calculator.
Treehugger.com, Embodied Energy and Green Building: Does it matter?
Deep Energy Retrofits
Deep energy retrofits (DERs) are highly problematic to historic preservationists. This isn’t because preservationists oppose energy efficiency; in fact, most contemporary, forward-thinking preservationists fully support energy efficiency and sustainability. Rather, preservationists object to the methods promulgated by many leading DER practitioners, which often require altering original architecture, and removing much historic material and replacing it with synthetics or composites. Many also question the energy required to manufacture modern sealants, adhesives, insulators, sprayed and extruded foams, and synthetic building components, as well as their environmental impact. When these concerns are combined with the embodied energy lost from destroying existing building fabric, the net energy benefit of these measures understandably gets called into question.
Not too long ago, a debate erupted in our home energy Twittersphere/ blogosphere about whether or not deep energy retrofits were compatible with historic preservation. The following links will take you to the main contributions of a number of us who participated in this debate. It’s fair to say we didn’t quite settle this discussion, but we certainly did manage to highlight the main issues and get them out on the table:
John Poole, Deep Energy Retrofits and Historic Preservation: The Beginning of a New Dialog (A Preservationist’s Technical Notebook).
Sean Lintow Sr, “Deep Energy Retrofits — The Conversation” (Homeowners and Trades Resource Center).
John Nicholas,”Deep Energy Retrofits — A Twitter Conversation”. (Efficient Energy Savers).
Peter Troast, “What is a Deep Energy Retrofit? Experts at the NESEA Conference Respond” (Energy Circle).
John Nicholas, “A Twitter Conversation — Moving Along, Part 2” (Efficient Energy Savers).
Allison Bailes, “Historic Preservation and Deep Energy Retrofits — Natural Enemies?” (Energy Vanguard).
Sean Lintow Sr, “Deep Energy Retrofits, Historical Properties, And The Conversation” (Homeowners and Trades Resource Center).
Leah Thayer, “Controversy over Deep Energy Retrofits“ (BPI Performance Matters Newsletter, April, 2012).
John Nicholas, “The Conversation Continues!“ (Efficient Energy Savers).
Peter Troast, et al, Mallett Deep Energy Retrofit Facebook Page.
Bouchard, Mallett House ‘a public demonstration of what can be done’ (Portland Press Herald)
Michael Anschel, The Folly of Deep Energy Retrofits (Hanley Wood’s Remodeling Magazine).
Martin Holladay, The High Cost of Deep-Energy Retrofits (Green Building Advisor).
Carl Seville, Historic Preservation and Green Renovation (Green Building Advisor).
Building Science Corporation, National Grid Deep Energy Retrofit Pilot.
Linda Wigington, Deep Energy Reductions in Existing Homes: Strategies for Implementation (PDF) (Affordable Comfort, Inc.).
Preservation-Sensitive Energy Reduction Projects
Many preservationists (myself included) believe home performance levels comparable to those achieved by DERs can be accomplished in very old homes by applying traditional methods of workmanship, along with more sustainable (less energy-intensive, non-toxic) materials. The key is to adequately learn how older homes actually behave as systems, then carefully plan a case-specific strategy for any particular building that synthesizes the best of old and new techniques and materials. The strategy should emphasize empirical testing and measurement, and reversibility/re-treatability of most specified treatments. Two projects undertaken in this manner are Historic New England’s Pierce House and Lyman Estate weatherization projects:
Dorchester Reporter, Pierce House Cited as Model for Improving Older Homes.
Historic New England, Historic New England Tests Energy Conservation at Pierce House.
Historic New England, Lyman Estate Weatherization and Energy Efficiency Project.
Article published in the May 2013 edition of Old House Journal detailing the historically sensitive energy retrofit of the Lyman Estate, Waltham, MA, undertaken by Historic New England. Current measurements suggest that a 40-49% reduction in energy consumption over baseline has been achieved, to date.
Removing and destroying existing historic windows, and substituting them with vinyl, fiberglass, or composite manufactured replacements, is the proverbial non-starter for all serious preservationists: Do nothing more than replace the original windows with something manufactured, and you’ve just about completely compromised the character of an historic home (along with its resale value, in many cases).
Often, window replacement is justified by energy concerns — a sales pitch largely created by the replacement window industry. But numerous studies by energy and preservation folks alike have shown that replacing original windows rarely improves the overall energy efficiency of an older building.
Here are a number of links related to window preservation, and the energy efficiency of old wooden windows. The Window Preservation Standards Collaborative (WPSC) links are particularly relevant here. The draft standard produced by this effort will form the basis for a set of National Window Preservation Standards, and energy efficiency and weatherization best practices for existing wooden windows are at the core of the WPSC’s draft standard:
National Park Service, Technical Preservation Services: Preservation Brief #9: The Repair of Historic Wooden Windows.
National Trust for Historic Preservation, These Windows Matter.
National Trust for Historic Preservation, Weatherization Guide for Older and Historic Buildings.
Traditional Building Portfolio – “Historic windows…represent an environmental bill that has already been paid” – Still No Substitute.
Larry Kinney and Amy Ellsworth (Center for ReSource Conservation), The Effects of Energy Efficiency Treatments on Historic Windows.
Window Preservation Standards Collaborative (WPSC) Home page.
Window Preservation Standards Collaborative (WPSC) Forum.
Window Preservation Standards Collaborative (WPSC) Review of Past Energy Studies (includes many studies that show old historic windows usually outperform manufactured replacement windows, often following only minor maintenance and inclusion of storm windows).
Window Preservation Standards Collaborative (WPSC) Weatherization & Energy Forum Page (includes identified best practices for weatherizing and improving the energy efficiency of old wooden windows).
Defendorf, FTC Rattles Windows Over Energy Savings Claims (Green Building Advisor).
Allison Bailes, Don’t Miss This Opportunity if You’re Replacing Windows, (Energy Vanguard blog). A relatively innocent posting about the need to properly air-seal window frames before replacements go in. However, the comment thread turned into an enthusiastic debate on the need (or the lack thereof) to replace existing windows in the first place.
Tricia Bennett, An Argument for Historic Windows in Terms of Sustainability and Authenticity, University of Massachusetts at Amherst (MS Word document).
Greening Existing Buildings and Sustainability
Sustainability and green renovation are often considered concomitant objectives, so any serious treatment of one usually includes references to the other. Here are some articles and books I’ve found useful. My own articles advocate developing sustainable, urban (on-grid) homesteads, based on older homes that have been made energy efficient, combined with micro-scale food production, wherever possible (this helps reclaim at least some portion of the original farmland previously claimed by the built environment).
Jean Carroon, Sustainable Preservation: Greening Existing Buildings, Wiley Sustainable Design Series, November, 2010.
Kevin Ireton, The American House: Where Did We Go Wrong? (PDF) (Fine Homebuilding Magazine).
Traditional Building Portfolio, Greening Historic Buildings.
Ted Cushman, House Flipper Heads for Zero-Energy Horizon (Hanley Wood’s Remodeling Magazine).
John Poole, Staying On-Grid, Part I: A Hybrid Approach to Sustainability (Building Moxie).
John Poole, Staying On-Grid, Part II: A Call to Arms to the Citizen-Farmer (Building Moxie).
John Poole, Earth Day 2012: Mobilizing for Water Conservation (Building Moxie).
Cluver and Randall, Saving Energy in Historic Buildings: Balancing Efficiency and Value (PDF) (Association for Preservation Technology International).
Linda Wigington, Thousand Home Challenge (home page).
A few of us have authored “manifestos” — short laundry lists of things one should, or shouldn’t, do, when dealing with old historic buildings. Mine is focused primarily on home performance retrofits, but has strong parallels with John Leeke’s:
John Poole, Historic Home Manifesto (A Preservationist’s Technical Notebook).
John Leeke, Old-House Mechanics Manifesto (Historic Homeworks forum).
Alternative Batt Insulation
The use of alternative air sealers, insulation, caulks, adhesives, and other materials in the pursuit of home performance retrofits whose manufacturing processes use less energy, and no toxic chemicals, compared to what’s currently available in the marketplace, is highly desirable. I’ll add links to such alternative products here, as they become available, or better known by me.
For now, I’ve focused on two alternatives to fiberglass batt insulation: Mineral wool batts, and recycled denim batts. I personally prefer the mineral wool batts over denim, mainly because of their fire and moisture resistance. Both batts have superior structural characteristics and “workability” that fiberglass batts simply do not have. When Roxul finally delivers formaldehyde-free mineral wool batts and boards to the United States (as many anticipate them doing soon), I will most likely standardize on these for insulating the attic floor planes and cellars of my own homes.
Here are some related resources:
Allison Bailes, Green Curmudgeons, Architects, and Outlawing Batt Insulation (Energy Vanguard blog).
Greg La Vardera, What you don’t know about Mineral Wool will make you look stupid (Modern House Plans blog).
Bonded Logic’s Denim Batt Insulation Product Page.
Roxul (Mineral Wool Insulating Batts) Home Page.
Building Science (General)
Energy Information (General)
National Trust for Historic Preservation Magazine, The Preservationist’s New Superpowers