This is a topic I had greatly researched at one point in time.
Trying to find the best ways to get a grip on increasing energy costs.
It seemed to make sense from a pure cost vs savings ROI but research is laced with such a diverse mix of good/bad stories where some say its amazing and others saying its absolutely a terrible idea.
Most pointing fingers to a "bad install" but never any real indication of what a "good install" would look like.
I tried to fill in those gaps, mostly all humidity related so I installed a whole home dehumidifier system that ties into the central system and I have humidify tracking for every room in the house via smart home stuff and the attic.
I also have a fresh air intake that keeps a small positive pressure in the home to help with potential VOC's and overall air exchange ratio.
So was ready to move forward with this... but another of my projects also just finished.
My whole home solar system is now connected and working.
This should be the worst time of the year and I am still covering over 100% of my electrical needs without issue and sending the extra to the power company.
So that kind of changes my perspective a bit. My ROI for the insulation will no longer be a 1:1 energy savings at the cost of electricity saved. It would be more like 1:5 as we still get to make use of energy savings by exporting more power to the utility for credit, but they only pay out at "wholesale" rate or whatever you would call it.
So I think this is more about the other benefits, having a home that can handle wider temperature differences from the outside for those 100 degree summers, potentially extending the life of the HVAC system witch is also new so a good time to start protecting it.
Perhaps adding more storage to the house by having the attic now a conditioned space.
Etc.
I am open to hear other benefits that I might look forward too, but mostly concerned with the warnings and that is why I am asking!
One thing that would make my entire decision much easier is just to start with personal testimony form anyone who has had an install done for say 5+ years and actually has checked on things to make sure your not developing any issues with moisture/mold and tell me the benefits you have noticed and if it was worth it.
If it seems safe, and I have taken the appropriate measures to make it safe then I suppose it would come down more to the benefits I would see compared to my cost to implement.
I live in Florida and have an older home. Was advised against spray foam because it doesn’t allow older homes to breath properly and will hide moisture damage. I went with blow in insulation
The difference between a house with spray foam and one without is the same as a kid waiting for the bus with a jacket and without or with a sun shade and without.
A/C won’t need to run nearly as much, everything is more comfortable, even our garage, which has no A/C is cooler in the summer.
With solar already covering your load, comfort and HVAC lifespan become the real benefits. Many long-term owners say temps and humidity stability are the biggest wins
In Florida if you put in spray foam you’re going to have a very difficult time preventing termites. God forbid if you ever got drywood termites there is t a company in the state what will fumigate your home.
Our house has spray foam, it had termites, and it got tented by Terminix.
Why?
You could just over insulate your attic with (paper-faced) batt or blown-in for a fraction of the price of spray foam and call it a day. Bonus: if the roof leaks or you have any other water issue, removing and replacing the insulation is a lot easier and cheaper.
Avoid spray foam
If you spray foam your house will stay more warm/cold for sure it great stuff. Just have to use a good company and not a fly by night one
Wait, how is this the "worst time of year" for energy costs. I'm in Florida and these are my cheapest months energy wise.
OP means it’s the worst time of year for generating solar power because the sun is low in the sky and not as strong as it is in the summer.
Thanks for the explanation.
I have foam and love it. Also makes the home much quieter.
I would consider installing a battery storage system instead of sending power back to the utility. They're getting better and cheaper every year. We dodged a bullet by voting against utilities eliminating Net Metering last decade--despite its confusing wording.
So utilities have begun working by themselves to reduce or eliminate what they pay you for the energy you're sending them. Might as well bank that energy for yourself. It's illegal in a lot of communities to disconnect from the grid, but that doesn't mean you need to feed it, either.
I have had foam insulation in attic now for over a decade and I also have radiant insulation under the rafters. Several things I have learned over this. While closed cell insulation is best to have down first, and to have every metal ac duct totally covered by, you need open cell on top of it to eliminate outside noise. Closed cell foam by itself can magnify outside noise in a roof. Open cell kills noise.
I live in the north, radiant insulation melts snow off roofs pretty quickly but if it is not done to the eaves it can create ice dams on the eaves. If you cannot run it to the eaves think about installing heated ice dam guards.
Never foam new construction with closed cell but if you are redoing old construction its great.
When installing spray foam in an attic, put wiring in conduit first.
Slow rise foam in interior walls cuts down on sound transmission between rooms a huge amount.
Insulation pays off now for most people, updating hvac pays off over years.
We DIYed spray insulation and are happy with the results. Process was not too bad (free blower rental with insulation purchased). I decided against spray foam because too many risks against no real benefit over spray insulation. Risks were too great (Florida).