What kind of HVAC pro do I need?
We own a 1956 brick ranch in the Washington DC area, with all the stupid design decisions you would expect to see for the era.
We would like to revamp the HVAC pretty much entirely. We would like a heat pump system to replace our AC and at least some of our heat, add in ERVs for our atrocious of ventilation, and also address radon mitigation since our half-basement/garden level averages about 3.5piC. We have a centrally ducted system for our AC right now, but those ducts are old and leaky and in our unconditioned attic. Even buried under a bunch of blown in insulation, I’m sure they are very inefficient.
The considerations for all these interrelated systems are so complicated that I think I need a pro to engineer a solution. The problem is I don’t know what kind exactly. Some kind of building engineer? An architect? Please help me understand what hero I should be looking for and where to find it! Thanks!
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You need a mechanical engineer with experience on residential renovations. They are not always easy to find. If you can't find someone local, try https://www.energyvanguard.com/. The principal, Allison Bailes, writes a column here on GBA regularly.
Thank you! Any suggestions on how I would search locally, aside from just googling "mechanical engineers near me"? Like, are there certifying bodies for residential MEs that might have lists or anything like that?
Yelp. And not Nexdoor. You want to know what dozens of customers think, not just one or two.
Also, see if you can get first-round help from a home energy audit. Many municipalities offer those for free, and even if you have to hire a company it can be worth it. It's always the first step before you get bids from HVAC contractors, who usually try to sell you an oversized system. (Not hyperbole.)
We did one when we first bought the house! We've made some improvements since then, like insulating the attic, so we may need to redo parts of it now. I would have to dig it up.
I don't know of certifying bodies specific to residential engineering. You can try sites like Yelp or Nextdoor but they don't cover every area--neither are available where I live--and I would fight to keep my information off those sites because homeowners don't always understand why designers and engineers do things the way they do.
I would do just as you say and search for MEs in your area. You could also check the PHIUS website for consultants in your area; if no engineers are listed but architects and designers are, try contacting them for a referral. You can also ask at your local HVAC supply house, check your municipality's business or chamber of commerce listings, business cards at the hardware store or diner, etc..
Here in DC building permits are public records and searchable online, if a ME stamped the plans his name will be in the file. If your area has something similar you could see if anyone has done a project like yours recently.
I don't think Yelp is going to be much help, because most people have only the vaguest idea of how a HVAC system works. Yelp will help you find someone who shows up when he says he will, does the agreed-upon work for the agreed-upon price, doesn't break anything and sweeps up when he's done. Those are all admirable qualities. But Yelp won't tell you if he sizes systems without ever getting out of his truck.
My guess is you are way over thinking this problem and are looking to throw sexy equipment at a perceived problem instead of doing the ugly hard work of insulating and air sealing an old building.
I do not think paying an engineer will get you a better radon system. Get a radon specialist and install a vent system under your slab and retest.
My opinion is ERVs are a great idea if it is bellow zero for weeks at a time where you live and your house is so tight the indoor humidity is over 60%. I think the Idea that every drafty old house in Texas must have a ERV is silly. Unless you have spent the time and money to achieve a blower door test under 1 ACH50 don’t waste your money on an ERV.
Are you willing to give up the room inside the conditioned space to relocate your ductwork? It is a big ask most people are not willing. If you ducts must live in your attic buried in in cheap fluffy insulation is as good as it gets. I say the greenest thing to do is continue operating the current HVAC equipment for as long as possible and avoid manufacturing its replacement for as long as possible.
Walt