Heating and cooling a ICF and SIP house
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Hello, I am building a ICF foundation and SIP home in VT.
I am looking for suggestions on the best affordable system to Heat / cool and vent this home.
Right now I am leaning towards a HTP Versa Hydro Heating system PHE-130-80S
I was planning on putting radiant in the slab, and have a forced hot air system for the 1st and second floor and prep for future solar hot water and prep for running a condenser to cool in the future.
My foundation is in and getting ready to pour the basement floor.
he house has a 1,000 sq ft foot print 28 x 26 salt box with a full walk out basement, with a living area 1 bedroom and full bath
first floor 1 bedroom 1.5 bath Cathedral living room
a second floor with loft and another bedroom.
I am open to suggestions and comments, but please understand I am not a Heating expert, and I do not stay in Holiday Inns so please speak owner builder understandable English.
My budget is very tight and I hopping to get set up in a system that I can add to in the future.
It would be so much easier for me to have an exchange of e-mails but I was told to post my questions here.
Not sure if I can post my house plans here or not?
Thanks for any feedback
Andy in VT
[email protected]
follow up questions
if I use a small furnace, and limited central duct work, howe do I cool or provide AC and will that also take care of HVAC venting for the sip house?
If I use mini splits system, how do I heat my hot water? do I use a on demand hot water heating unit?
Thanks
Andy in VT
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Replies
Andrew,
My first reaction is that your heating system is unnecessarily complicated and expensive. You've got a boiler and a hydronic distribution system, as well as an air handler and a forced-air distribution system. That's not an inexpensive way to go.
if your budget is tight, I suggest that you follow some of the advice in this article: Heating a Tight, Well-Insulated House.
Probably the cheapest way to go would be a small furnace with limited ductwork in the center of the house (not the perimeter). If you can get your heat loss rate low enough, you may be able to heat the entire house with three ductless minisplit units.
Remember, the tighter and better insulated your envelope, the lower your rate of heat loss and the simpler your heat distribution system can be. It's always better to invest in a better envelope rather than an expensive HVAC system.
martin, thank you for your answer, but I still have questions!
OK if I use three mini-split systems, What about my hot water?
Do I do that with a heat on demand instant hot water unit?
should I still put radiant pex tubing in the slab?
what if I want to take advantage of solar in the future?
how will that work with a the mini- splits?
thanks
Andy in VT
Andy,
Q. "If I use three mini-split systems, What about my hot water?"
A. You would use a water heater.
Q. "Do I do that with a heat on demand instant hot water unit?"
A. That's one option. You might want to read:
Are Tankless Water Heaters a Waste of Money?
All About Water Heaters
Q. "Should I still put radiant pex tubing in the slab?"
A. Unless you are installing a hydronic heat distribution system, there is no need to do so. But it's important to install a continuous layer of horizontal foam insulation under your slab.
Q. "What if I want to take advantage of solar in the future?"
A. I'm not a fan of active solar space heating equipment, especially in Vermont. Passive solar design strategies make more sense than active systems.
A. "How will that work with a the mini-splits?"
A. Passive solar design solutions work well with minisplits.
Martin, thank you for your answers.
However, it seems we are still dancing around and not getting to a definite solution. ;-O
I can read all your musings and they all seem to lead around in a circle and not really define one solution.
Let me try again.OK If I use the mini split ductless system, one fore each floor ?
is that what you are suggesting? the mini- splits will heat , cool and provide fresh air is that correct?
what type of water heater is cost effective and efficient !
I would prefer a gas unit, do you have a suggestions on a gas water heater? Brand and size?
Passive solar, for us who do not sleep in holiday inns or have more than a high school education the difference is the active heats water, while the passive is solar electric is that correct?
I do appreciate you time and responses. But for me I need a bit more information that leads to say Eureka! instead of uh?
Andy in VT
Andrew
few things to help.
First....
checkout this, it can be a great source of info: http://www.google.com :)
For the mini splits, you will still need a stand a lone ERV/HRV to provide fresh air exchange. The mini split will provide heating and cooling. Think of it just like a furnace without ductwork....and the head unit mounted on the wall. Since they are heat pumps, you may need to have a backup source of heat, such as cheap baseboard heaters here or there just in case.
If you are going with an all electric system, but not go with an electric waterheater such as a Marathon or something? It is a tank heater with is super efficient.
For the pex in the floor, I would suggest installing them anyway, even if you may not use them. It is easier to get them in the slab now then it is after the concrete is there! It way help you out for resale too. You may find down the road you want to add a small boiler or something to provide hydronic to the basement.
Also....I do not understand your Holiday Inn expression.
Take some of the items listed above and google them. You will find tons and tons of info out there on them.
Andrew,
Unfortunately, when it comes to equipment specification, there is no substitute for study. And if you are involved in a residential design project and find yourself in waters that are out of your depth, it may be time to hire a designer, an architect, or an HVAC consultant. If that's not an option, then it's time to Google, study, and visit the local library.
Q. "OK if I use the minisplit ductless system, one for each floor?"
A. That approach can work, as long as you have an open floor plan, a very tight envelope, and flexible homeowners who leave bedroom doors open during the day.
Q. "The minisplits will heat, cool and provide fresh air - is that correct?"
A. Not quite. They will provide space heat and cooling, but you'll need a separate ventilation system. For more on ventilation systems, see Designing a Good Ventilation System.
Q. "What type of water heater is cost-effective and efficient?"
A. That depends on whether or not your house has access to natural gas. It also depends on the local cost of electricity, the size of your family, and your hot-water usage pattern. I suggest you read the articles that I linked to in earlier answers for more information.
Q. "I would prefer a gas unit."
A. It's your house, so you get to choose whatever you want. If you don't have access to natural gas, however, remember that propane is a very expensive fuel.
Q. "Passive solar, for us who do not sleep in Holiday Inns or have more than a high school education, the difference is ....?"
A. Here's a link to an article that will explain what you need to know: Cost-Effective Passive Solar Design.
Q. "The active [solar system] heats water, while the passive is solar electric - is that correct?"
A. No. Passive solar design principles emphasize orientation (aligning the house so that the long dimension runs east-west), house shape, window placement and orientation (with about half of the windows facing south, and very few facing the north), and the inclusion of thermal mass.
Thank you both for your feedback and suggestions. However, Your advise still leaves me with no clear direction. I positioned the house with the long side of the salt box roof facing close to 194 degrees, in hope of someday adding some solar , either hot water or electric. I have googled, studied, read and it all seems greek to me and nothing says to me , here is simple solution. Propane is expensive but this house is going to be pretty tight and is only a 1.000 sq ft foot print, with what I think is a pretty open floor plan.
Pus with propane I can direct vent, and there seems to be no shortage.
I need to vent the house and I need hot water.
Why do I fee like I am re inventing the wheel?
Jesse, My reference to the Holiday Inn is my small bit of humor relating to some commercials they , (HI) used to run about people who had the answers or solutions to someone elses's problems since they had just stayed in a Holiday Inn. ;-)
I thought it was a simple question, what is the most cost effective way to heat , cool and vent a sip built home? The answer is blowing in the wind.
I can not afford to hire a designer, or architect and I thought one of you advisors would look at my plans and say something simple I could understand and put into place.
"Probably the cheapest way to go would be a small furnace with limited ductwork in the center of the house (not the perimeter). "
Ok if I go with a small furnace with limited duct work, can I use the same duct work to bring ins fresh air and vent? and what kind of hot water heater goes with that kind of system and will allow me to upgrade to solar hot water in the future ?
"If you can get your heat loss rate low enough, you may be able to heat the entire house with three ductess minisplit units." But then I still have to heat my hot water and still vent right?
I am building this house to rent as a accessible vacation rental, so folks who happen to be in a wheel chair can also vacation in VT. My hope is that I will also be able to donate vacation time to those who need a vacation, like a disabled Veteran.
You all have a great day.
Andy in VT
Andrew,
I'm happy to answer you questions, but there are two steps to this process. After I write an answer, you have to read what I write. You are beginning to ask the same questions twice.
Q. "OK, if I go with a small furnace with limited duct work, can I use the same duct work to bring in fresh air and vent?"
A. Yes. It's all explained in the article that I already linked to. Please read the article to find the answer to your question: Designing a Good Ventilation System.
Q. "What kind of hot water heater goes with that kind of system?"
A. Any kind you want. You can choose a tank-type heater fueled by propane or electricity; a tankless heater fueled by propane or electricity; or a solar hot water system with a backup heater fueled by propane or electricity.
Q. "What type of water heater will allow me to upgrade to solar hot water in the future ?"
A. Any kind of propane or electric water heater will allow you to add solar later.
Q. "I may be able to heat the entire house with three ductless minisplit units -- but then I still have to heat my hot water and still vent, right?"
A. Yes. I already answered that question. If you want hot water, you need a water heater. If you have a very tight house -- and it's a good idea to make it as tight as possible -- then you need a mechanical ventilation system.