In several industry conversations over the past few months, there’s been debate about whether we should take a “staged” retrofit approach. I've got my thoughts
There is no doubt that an all-at-once approach allows the biggest results at a lower cost. It’s often most cost-effective to do several things at the same time, or in particular orders. Yes, reducing the load makes more sense before replacing the air-conditioner rather than after. And if we’re really thinking comprehensively, we get to “tunnel through the cost barrier” as Amory Lovins puts in, reducing the load enough to start dropping tonnage, eliminate sytems, and simplifying mechanical solutions, and avoiding some costs altogether.
But in today’s world a couple steps at a time is the way most homeowners will tackle efficiency improvements in their homes. And at the end of the day, homeowners decide.
What do you think?
All at once. Get it done. Entire 5 key categories of green should be done.
IMO and experience of course a single comprehensive retrofit is idea for many reasons. But I call total BS on calling anything but that "not true home performance". The truth is the homeowner does decide and you can have all the financing in the world and some people just wanted to work on it the way they do everything else in the home.. a little at a time. As long as your original road-map facilitates a staged retrofit performed in a comprehensive manner(where it is ordered so it can be done correctly and the homeowner understands that is the path ), and the homeowner is aware of the added synergy of doing it all at once,.... then your HP is in tack.
I am all for comprehensive phasing. All at once is brilliant, but what percentage of the projects that present themselves are comprehensive deep energy retrofits? Not many, I'm guessing. We work with clients to create a roadmap with 3 to 5 phases. Key for success? After much frustration and not-always-silent condemnation of contractors who don't think comprehensively: comprehensive bid documents that outline the phases we recommend. This allows the homeowner to stick to their guns in terms of what they want/have decided on and not get derailed by errant contractor who gets a great discount from his buddy for the minisplit that they both think is the silver bullet solution, damn the wind blowing through the envelope.
I no longer carry out the HP site work myself. Working with clients and trying to bring contractors along in the HP arena at the same time is a monster challenge. I just posted a blog entry about a paper I'm writing that started with a contractor who was bidding on a job. This contractor, after being briefed on the project by me, told my client (shall I repeat this was **my** client, not an episode of 'Love It or Leave It') that the reno was not worth doing because it could be more than 30% of the appraised value of the house, and they should scrap the project and build/buy new in a greenfield development. Now, while that figure may have been correct, who cares? My client was not doing the retrofit so they could sell the house. They were planning to do the work, in phases, as they could afford to, so that they could stay in the house and neighbourhood they loved.
Bumping up against that kind of attitude from a contractor makes it very difficult to:
It's really amazing how people will come in, get only a tiny cursory understanding of the clients needs and objectives, and start mucking with a comprehensive design plan. Funny you mention Mini-splits. That's what one contractor suggested on one of my recent projects.
Do they really want me to make them look stupid and unethical? That's the position they placed me in, having to have unnecessary conversations with the client that is not billable OR productive steams me. Waste of 3 peoples time, really. And now I have to take their number off of my recommended contractor list.
Bummer is, although they are totally product oriented and can't do comprehensive design to save their lives, they do really nice work. Wish they could stick to what they are good at.
Amen to that, Ted. Our list of contractors gets pruned regularly because of this, and people who do good work in their area of expertise get no more jobs out of us, simply because I don't have the bandwidth to find out if they are 'convertible' to being part of a team that looks at HP first, then the product. Some can, and do, and I love that.
MIni splits...yup...and don't get me started on contractors who swear by bubble wrap insulation vs. spray foam...
It depends on the capital available, investment lifetime considered, and the state of the mechanical equipment. The "tunnel through the cost barrier" savings comes from changing to a different mechanical system, e.g. steam boiler to minisplits. This is a one time savings from a project ROI perspective, and generally only applies to oil-fueled, steam, or other such large systems.
Mechanical system is in bad shape => all at once
Mechanical system has usable life left => stage it matched to expected remaining life of the system
Other scenarios are more dependent on homeowner preferences for capital outlay etc.
Really good points, Matthew. One thing I still wonder about in your second scenario, though: when envelope tightening measures cause a mechanical system with lots of usable life to becomes egregiously oversized. Is there realistically a point where the efficiency losses over the remaining usable life of the system outweigh the capital cost of replacement?
I'm asking openly, as I'm not that familiar with HVAC-related economics. Thanks.
The unit will cycle more, which will cause an efficiency drop. The economic comparison is then the cost of the extra fuel use from cycling, versus the value of delaying the capital expenditure. Generally the value of delaying is worth much more than the efficiency loss, but there may be some situations this isn't true.
If the "why" of your initial visit includes comfort or control, your solution is likely to fail if your equipment just went from 50% oversized to 150% oversized.
Those simple mistakes create a big opening for those who come behind you to make you look incompetent, even stupid. So GENERALLY I'd say there is cost to the result, to the client, to you, to accuracy of savings, and to public perception of Home Performance as solving comfort and energy problems.
In my experience, economics really don't drive the homeowners' decision, if you ask a lot of questions. They just want to be comfy, reasonable bills are a nice side effect.
Making the equipment drastically oversized will often make the comfort problem worse, meaning you probably didn't fix the problem you were called for. I used to do that. Very often when I followed up I fixed one room but screwed up another (as an insulation contractor). That was before I had any understanding of HVAC, now I know I made their HVAC way oversized so it cycled less and made rooms with long duct runs more uncomfortable. Which means I didn't really solve the problem.
Like Ted says, when you talk commercial, numbers come more into play. Residentially, people just want a warm bedroom, bathroom, kitchen, whatever. I don't get called for awesome houses, I get called for sucky ones with problems.
This is good to know and be able to speak intelligently to for certain homeowners, thank you. I've run into a fair amount of people for whom it really does come down to $$$ (more so in SoCal than when I was in Oregon, but that's a whole 'nother topic). If I were ever selling home performance to an actuary, I can see this being a valuable part of the dialogue.
That said, I'm with Ted and Nate on the decision drivers for most people being non-economic. I don't think penny pinching is worth being less comfortable and not in control of their largest investment, especially once you show them that there's a better way to live. We shouldn't ignore peer pressure, either, as examples of affordable, high-performing homes become more prevalent. For better or worse, the years to come will bring more customers that are investing in home performance to keep up with the Jones as for any other reason.
Nicely put Griffin.
Matthew - trying to squeeze every last bit of life out of equipment is often analogous to attempting to squeeze a little bit more juice out of an orange when you have a whole lot of juicy oranges on the ground getting ready to rot. It's allowing obsession to overcome logical analysis and good design thinking.
For residential, just fix the house. Design, mobilization, and making sure problems are FIXED should take precedence over obsessively chasing pennies and ignoring true value. Don't leave it a frankenstein monster because crappy equipment "had some life left".
For commercial scale design it get's a little more challenging. But rather than thinking "squeeze the life out of that dry orange" I'd look at depreciated value (having an Economics background causes me to want to do present value/future value analysis in these cases). Once you have the remaining value of the existing equipment and know cost of capital (cap rate), you know what you are throwing away and how quickly throwing it away is justified.