More Musings of an Energy Nerd
I live in a 42-year-old house that has never been tested with a blower door. When I’m standing at the sink in January, I can feel cold outdoor air entering the house through the crack between the nearest window and the window stool. My bedroom windows show subtle signs of black mold on the lower sash rails. My house doesn’t have a whole-house ventilation system. None of these facts is unusual; almost all of my neighbors have similar stories to report.
For the last 23 years, I’ve been writing articles that advise builders on how to build comfortable, energy-efficient homes. I know that homes need to be as airtight as possible. I know that thin insulation and leaky windows lead to higher-than-necessary energy bills. But for a variety of reasons, it’s hard for me to implement all the good advice I dish out to readers.
Is my furnace filter dirty?
In my recent review of Allison Bailes’s excellent book, A House Needs to Breathe … Or Does It?, I mentioned Bailes’s advice on determining when it’s time to change the air filter on a residential furnace. The best method, according to Bailes, is to use a manometer to measure the pressure drop across the filter. You should check this pressure drop regularly; once the pressure drop increases to twice the pressure drop measured for a clean filter, it’s time to change the filter.
A few HVAC technicians may employ this technique, but for the vast majority of Americans, the advice isn’t particularly useful. Try as we might, even those of us who aspire to reach nerd nirvana aren’t likely to make it there. Our houses will always be leaky, our insulation R-values will always be inadequate, and our furnace filters will be changed (or…
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29 Comments
This one hit home, thanks Martin.
We are human. We do what we can. Good, pragmatic New England advice.
One good thing going on in MA and RI is that rather than give utilities the green light to add new facilities (of financial benefit to them), there are programs (e.g., MASS Save) which will do free energy audits, and have an approved contractor come out to do energy improvements to your home or business. That way, the utility doesn't need additional capacity and new facilities, the demand for energy is reduced--along with the utility bills of consumers and businesses.
Some of the energy improvements are free of charge to the homeowner (e.g, light bulbs). Others are done so cheaply, I can't even buy the same materials as MASS Save charges for both the materials and completing the labor and any followup testing. (not to mention actually completing the work, and in a single day! ;-)
Low income households can get a free refrigerator to replace the old inefficient fridge, and free insulation upgrades, etc. Others get that highly discounted package for air sealing improvements, insulation installed, and other freebies. They also have an online catalog of various energy efficiency devices that consumers can buy directly at discounted prices.
Besides hiring contractors for the work, there are also short classes for contractors on various energy efficiency topics.
All in all, a great program for consumers, businesses, contractors, and especially for old, inefficient housing stock and low income households. And it reduces the need for additional facilities, reducing energy demand rather than increasing energy production.
Robert,
Any homeowner or renter who is eligible to receive services from a subsidized weatherization program should certainly take advantage of the program. Most of these programs have very good track records.
I believe that any homeowner in RI and MA is eligible for a free energy audit including blower door test, upgrades from incandescent to commodity LED lightbulbs, and central heating setback thermostat (unless they already have them). Some get free, others get highly subsidized charges on what the program is willing to do after their free energy audit evaluation.
My mother (low income in RI) got everything free the first time, including energy audit, LEDs, setback thermostat, new refrigerator, air sealing work, weatherstripping doors, and insulation installed for some uninsulated areas. Her electric bill was reduced more than half after the decades old refrigerator was replaced. The next year they emailed me a quote for additional work they were willing to do, to blow in wall insulation, subsidized but not free (which she declined).
She could have gotten a free central heating furnace replacement from a different program, but I missed that one.
My girlfriend in MA had very low charges for attic floor air sealing and insulation increased from almost nothing to R-50 cellulose, polyiso attic hatch door and basement door to bulkhead, weatherstripping and free thermostat and LEDs. Later got financial rebates for installing mini splits, HPWH, and removing all heating oil infrastructure in the home.
Even when not free, the reduced costs of energy improvements is impressive. It would cost me more to buy just the materials for these renovations than the subsidized charges of their crew doing evaluation, materials, labor and before/after blower door tests. However, they will only perform what they consider the most important upgrades up to some limit (I guess one day's work for the crews hired to do this work). You can ask them to return in the future to do another audit and additional work.
Since these are state programs, I wonder how widespread the might be. Could be one way to upgrade many poorly performing homes on a more widespread basis.
Martin,
I think this highlights some of the good advances in energy codes, and code requirements in general. It's extremely difficult to perform an effective energy retrofit that is cost effective, as you've pointed out. As we require better standards, which ultimately do not cost extra, but require attention to detail, I think we'll get 'there'. Air sealing after the finish materials have been put in place is practically impossible, yet is more important than most other aspects of the building. I think a lot of us who comment here frequently struggle with balancing suggestions that are physically effective, and financially prudent.
A little money buys a lot of energy, but very little labor, and that's the killer.
Kyle,
I agree with you that our energy codes are inching in the the right direction. In jurisdictions where the newer versions of the energy codes are actually enforced, this has made a real difference. Unfortunately, in much of the U.S., there is no effective code enforcement mechanism -- especially when it comes to energy codes.
But like you, I'm optimistic that eventually, we'll get there.
Great perspective here, thank you. I've been in this same thought space for some time now and think their may be some possibilities outside of codes and policy. Having done many "energy audits" and the like, I've realized that process is just inadequate. I'd like to pose the same question here that I've been asking people in my community.
Would you pay for someone to help you plan out what your home will need, and when, over the next 10 or 20 years? How much would you pay?
The idea is to identify the most important questions, tests, and analysis needed to reasonably predict when roof, HVAC, water heaters, etc. will need to be replaced and help the homeowner make good decisions ahead of time. The cost will have to low enough that people will actually do it.
For homeowners the the value is in avoiding emergency replacements and preparing for the costs of these projects (capital needs). Necessary replacement being the best time to make improvements, this may be a chance for efficiency and electrification when homeowners have opportunity to make decisions not under duress.
We'd provide design and management when the time comes and identify contractors to work with who are able and willing to do the work well.
For the contractors the value would be less design responsibility and the ability to schedule jobs in the off season and start reducing the number of emergency replacements they have to deal with.
I'd appreciate any thoughts on the idea.
AKosick,
I've had those (lifecycle studies) done for both commercial and multi-family residential buildings. Many condo boards use them to identify how much to put into their capital reserve funds. I don't know if there is a viable business model to provide them for single family dwellings. You may need to do an awfully high volume to generate enough cash-flow at the price you could charge.
Thanks Malcolm
That's exactly what I'm worried about but I think leading with homeowner education through a website and using web form to start the process might help make it worth it by addressing comfort, air quality, durability concerns as well. There are a lot of homeowners with minor problems that they may not be ready to solve in isolation but in combination with some planning might make it worth more to indivduals than to a condo association. We'll see.
AKosick,
Maybe home inspections are a good metric to use on possible pricing? They do have an advantage though in that people typically get them when buying a new house where there is a lot at stake financially.
I briefly entered a low return part of the market offering what I called "a second look", reviewing designs and working drawings, offering suggestions for improvement, and highlighting possible problems. It was interesting and fun, but not worth pursuing based on what people were willing to pay for it.
Good luck. I think it would be a valuable service to provide.
A. Kosick,
I had a business for many years providing the service you describe. Here in Vermont, the term for the service is "capital needs assessment." My services included site inspection, photography, and preparation of a report with a narrative description of existing conditions, an estimate of the longevity of existing capital equipment, and a 30-year spreadsheet showing annual capital needs (and the recommended annual deposits into a fund, called a replacement reserve fund, to cover capital needs over the next 30 years).
My clients were owners of multi-family residential projects; generally these were nonprofit agencies that provide housing for low-income families. Each client paid me thousands of dollars. I can't imagine that many homeowners could afford my services.
Thanks for the reply Martin.
I hear you, but I honestly think that for a single family residence, with some well designed software, and also addressing comfort, air quality, and durability concerns there may be a sweet spot where this could work.
If it doesn't there's something kind of tragic about it. As I have dug into it, the complete lack of planning and forethought most people have concerning the largest asset they are likely to own is honestly ridiculous. I'd argue it's a significant underlying problem that is perpetuating a lot of other problems, and for that matter, it's likely to significantly hinder electrification and adjacent climate solutions.
I guess I'll see and report back.
A. Kosick,
Whether or not the cost and expense of a capital needs assessment is tragic, and whether or not the current situation is "honestly ridiculous," is a matter of opinion. But it remains a fact that the services you think homeowners should take advantage of are more expensive than customers are willing to pay.
To be clear, it's not the cost of the assessment that I think is tragic, it's the fact that people don't have a plan for maintenance, replacement, and improvement. Which is made visible by shear quantity of emergency equipment replacements.
As depressing as it is, it's helpful that you think the cost isn't going to sell. Thanks again.
Lots of simple stuff folks can make a big difference in energy use and reduce Global Warming. Add insulation to the attic is not hard for the able-bodied and not very expensive and where most of the heat is lost. Seal leaks on the outside of windows and doors. Add warming curtains. Set your heat to 68 degrees in winter, 78 summer with AC and set heat lower to 62 degrees for overnight. Turn down the hot water heater to 120 degrees or lower. Use less hot water, showering every day is passe and generally unhealthy unless you do it for work reasons in the evenings. Wash clothes with cold water generally. Don't use the fireplace except for a few special occasions and pull the damper shut when not in use. Upgrade to heat pump when the AC fails and needs replacing or is getting old.
Add solar or wind if you can get a break on cost and your house or land are appropriate and the utility is allowing net metering, many of them are fighting it Tooth and Nail sorry to say and should be outlawed.
Drive an electric hybrid, some have higher MPGE than Teslas and, major rebates will soon be available.
Its true we should be getting more help from local, state and federal agencies, it would save the country way more than it cost and will help save us from Mega Bad Weather Conditions coming down the pike. And help folks save lots of money and live much more comfortably.
Come January federal funds will be available for most of what was suggested, and more, and in rather large amounts credited to the homeowner.
VPC2,
I admire your enthusiasm, but some of your advice needs to be rearranged, especially when it comes to air sealing.
I'm not sure what you mean by "Seal leaks on the outside of windows and doors," but weatherization experts don't recommend anything like that. I advise readers to refrain from implementing your advice to "add insulation to the attic" until first performing the air sealing work that really matters -- namely, air sealing work at the ceiling plane, under any existing attic insulation. Those air sealing efforts are much more important than "sealing leaks on the outside of windows and doors."
When it's worth it, or where we need to, we make the time. If you're comfortable,. enjoy the view and southern sun and toss another log on the fire. In my old house, when my back started aching from hauling firewood, and mold started creeping up the living room wall, I had to do something. A few years later, we haven't lit the wood stove for five years, we love summers with the minisplits and I have a basement that stays in the mid 50's all winter where I can keep my tools, now that they're out of the truck. One of the best parts? The HRV!
User 1072251,
I'm glad you're enjoying your new minisplit and HRV. Transitioning away from burning wood is good for the planet.
Thanks, Martin. This isn't the first time you've reminded me that, although I should continue to try to make my old house more comfortable and energy efficient over time, I shouldn't be obsessing over it or letting it rob me of quality time with my family.
Another aspect of this was brought home to me last week. A very bright and diligent GBA reader is building a house near me. He has taken a lot of his details from this site, but sometimes the more general advice conflicts with regional concerns.
He had hoped to use either his wall sheathing or WRB as a primary air barrier, and transition to an interior one on the roof assembly. But here in the seismically active PNW, it's important to overlap the structural sheathing from the walls onto the heels of the trusses, making that air-barrier transition much more challenging.
Sometimes the implications of incorporating the high performance details featured here aren't obvious, and can have knock on effects you haven't anticipated, even for thoughtful builders.
Though we're not in a seismically active area, we made a point to overlap our structural sheathing up onto the raised heels of our trusses and down to our mud sill. We chose to use gaskets under the sheathing along the top plate of our exterior walls, and on the top plates under the drywall of all walls inside the house. That, combined with lots of other air-sealing methods, produced a 1.6 ACH50 for our house - which stunned the blower door tester and building inspector. Apparently there aren't many other higher performing houses in our community. My sister and I (both in our 60's) did all of the air sealing, and most of the insulation ourselves (along with much of the other work on the house). And the results are particularly gratifying with the severe winds and cold that we are receiving today.
Debra: Excellent solution! We need to get the word out that high performance buildings are very achievable! Congratulations on yours. I'm attaching a link to the Conservation Technology website. They sell a number of helpful products; including a selection of EDPM Building Gaskets. http://www.conservationtechnology.com/building.html
In our builds, we have also found it difficult to make the exterior air barrier physically contiguous with the interior ceiling air barrier. But we have found that starting the interior barrier at the exterior wall top plate, works very well. There is always a potential for an air leak under the sheathing around the top of the sheathing, but we've achieved 1ACH50 and a few around .5 without that physical continuity. Details are critical of course, but we are not seeking perfection. Like our neighbors to the east, Pretty Good is fine with us, and most important, doable by the majority of builders in the US.
I wasn't so much commenting on how difficult the details are to execute, as that anything new has to be integrated with the already existing construction practices. If you simply picked your high performance details from the ones featured on GBA, you could have all sorts of unanticipated complications.
So for instance a lot of the foundations shown are monolithic slabs, and many built on compacted fill. Under our building code both of those move the project from the prescriptive paths available, to requiring a structural and geo-technical engineer.
Similarly the details for foam between foundations and slabs are often shown with the bottom plate cantilevered over the stem-wall. Building codes differ as to how much bearing there must be, and some preclude cantilevering all together.
The devil is in the details.
I really can relate to this article. My wife and I just bought a 1924 brick bungalow in a suburb just outside Chicago. No insulation, lath and plaster over 1x2 furring strips on brick, oversized 140K BTU boiler, large chimney, some cheap leaky storm windows, and interior walls open to the attic joist bays.
My plan is simply to take simple approaches to tightening it up. Insulating the attic rafters, new storm windows, a correctly sized boiler when this one goes, weatherstripping, air sealing in the attic and basement, more energy efficient appliances and maybe a minisplit or two for A/C.
But these are as far as I'm going with it. Anything more is money we don't have or care to spend. Also many of those improvements would simply compromise the old look and character of the home, which one of the main reasons we bought it.
Personally for us, I can't see it cost effective or sensible to do any
major expensive projects beyond what I mentioned above in the name of energy efficiency. We are in our 50s and don't have the money or really the interest to go that far with it, although I can admire those younger building new homes or gut rehabbing an older one and achieving this. Doing the improvements I mentioned will themselves make a big difference, not cost too much and make utility costs more reasonable.
The plaster is in excellent shape, woodwork is beautiful and all original. Windows, doors, floors all original. Hot water radiator heat which we love. Yes we have to use window units, but we are ok with it and bought higher quality quieter units and two cool the place fine. Minisplits might be an option at some point maybe. Also, It's just two of us in the house. I would never think to cover the exterior brick with foam insulation, or rip out the plaster that's in good shape and beautiful trim to add insulation, or cut up the walls and ceilings with soffits for ductwork. If others, younger couples and such, want to do that, spend the money to gut and redo it all and add a lot of high tech HVAC and such that's fine more power to them if they have money and want a contemporary look in their old home. But for just not for us.
We bought our 85-year-old home in the midwest 6 years ago. I work in a field totally unrelated to building science, and I knew nothing about home energy efficiency, but I was willing to learn, with GBA as my main instructor (along with Musings). I know the monetary break-even for the work I and contractors have done will take several decades. One thing this article made me consider was the non-monetary returns as well: all the learning, all the conversations with family and friends, all the contemplation on my family's values reflected in a building's life cycle. I have to focus my non-monetary resources--time, attention, creativity--somewhere, and I have found that improving my home is a regenerative way to spend those resources. I do sometimes get obsessed and stressed, but moreso I am stretched by the learning.
We've had mini-splits installed in December the last 2 years (first on the upper floor, then the main floor), and I convinced my family to celebrate "Splitsmas"! This is a new stupid family tradition, one that is equal parts mocking and genuine, and it represents the tilting at windmills attitude that comes with doing piecemeal DIY energy renovations in an old house in the midwest.
So I'm grateful for all that stuff. But there's something that actually matters with the windmill-tilting (or at least I am willing to carry this delusion with me): by normalizing this, doing the hard work that isn't monestarily cost-effective, we are paving the way for others in our community who want to know and do more. In my community, this looks like people asking me about mini-splits, solar panels, and attic air-sealing, which are all things most people where I live have legitimately never considered. Not saying that buying mini-splits is that hard, except when the contractors who do it have never installed anything other than the wall mounts, don't insulate the wall perforations, and recommend double the necessary size. The hard part is learning how the units will work in MY home, asking for advice, learning to do my own load calculations, since there is no one else I can trust here to do that. Having done the homework, I can hopefully help people avoid some of the time, creativity, attention, and money that I've had to spend.
I'm very appreciative of this community online as well. This post, particularly, is reflective of the generous spirit I have found here. The combination of unwaveringly rigorous adherence to scientific principles with the willingness to allow for imperfect application of those principles by real human beings is sublime.
d_w,
What a heartening post as we head towards the new year!
Wonderful! I am a new DIY homeowner GBA member, and I have read a lot of the very technical articles on GBA in the last few days as I try to figure out how to do the best we can by this old house of ours. I was starting to panic, feeling that there was no hope of meeting the outlined requirements and proposed solutions with our rough-built 1958 One & 1/2 story log house. Then, because I tend to persevere, I was starting to form this idea of necessary imperfection. We would try our best and it would have to do, even if some would find the results deficient. After reading this, I now feel a renewed sense of enthusiasm for the work ahead.
Thank you for this,
Yvette
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