Return to the Heating & Air Conditioning Forum | Post a Follow-Up

Radiant Hydronic Heat downstairs - what type upstairs?

Posted by montel (My Page) on
Thu, Apr 14, 11 at 12:42

Originally we were planning for radiant hydronic in both our slab downstairs and in our upstairs - which has our great room, kitchen, dining & living room areas all open - to do radiant for both areas is coming in at over $25K...

We are looking at alternatives to lower the cost. Since our home is fairly open we are toying with the idea of doing the radiant in the slab for just the downstairs, then doing a different heat source just for the upstairs. We feel that the heat will tend to rise somewhat from downstairs regardless, and we might need very little heat upstairs. Some homes in the area never use the upstairs radiant. We do have some decent passive solar exposure so we will get some solar heat on sunny days.

So far we have looked into doing simple radiant water baseboards in 3 locations. We are also really interested in the idea of a ductless mini-split heat pump for the upstairs. An 18K btu unit could easily handle our heat load - plus even though we almost never need AC it could do that as well...

Decisions are still to be made - we signed our building contract yesterday with $20k budgeted for heat - if we can do radiant in-floor for that cost we will do it.

We have looked at Warmboard for the upstairs, but the $10k additional cost for just the floor boards over a standard sublfoor was to high.

We have also looked at Ecowarm, Quik Track, and they all seem a bit high per sq. ft. for what we need. Staple up was suggested but seems a bit lower in efficiency, but would be cheaper.

We were quoted $9-10 sq/ft for basic radiant hydronic in floor heat.

Total heated 2800 sq. ft. - upstairs 1200 - downstairs is 1600.

We are on the west coast in a very mild marine coastal climate. Our coldest design day is 33 deg so not a cold climate! We really need no AC at all.

Follow-Up Postings:

Further Information

Quick follow up:
We have Natural Gas - we are planning on using a Polaris condensing tank water heater for both the domestic hot water and the heat source for the Hydronic in floor heat. We will use a heat exchanger.

Currently we are looking at 1 zone for downstairs with 5 circuits or loops.

If we did go with radiant hydronic baseboards upstairs there are 3 walls under windows that would never have furniture on them.

Also, I thought it might be possible to run the 3 baseboards upstairs as separate zones with pex, then if we wanted to upgrade to under-floor heat in the future we could do so pretty easily...we are planning for a floating floor upstairs (laminate or engineered)

RE: Radiant Hydronic Heat downstairs - what type upstairs?

If your climate is mild, a mini-split or regular heatpump might be perfect for your upstairs. If you electricity is expensive you might want to reconsider.

RE: Climate

We are very mild climate Marine Zone 3

RE: Radiant Hydronic Heat downstairs - what type upstairs?

Anyone else have ideas or coments?

So Far My Choices are:
1. Radiant Under Floor throughout - Most Expensive, probably way over budget
2. Radiant hydronic in concrete floor slab downstairs (bedrooms, laundry, hallway and full baths) - Radiant Hydronic Base Boards (Runtall) type upstairs for at least 3 zones - These would run on the same system as the downstairs in floor heat, and run at the lower temperature
3. Radiant in slab downstairs - 1 18,000btu Mini-Split ductless heat pump upstairs

These seem like my options - would love comments pro and con on any!


 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!

Return to the Heating & Air Conditioning Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Please review our Rules of Play before posting.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.

Learn more about in-text links on this page here