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How to heat a standalone office / bathroom

onobed Member Posts: 1
edited June 30 in THE MAIN WALL
I am building a standalone office with a bathroom. The bathroom is 85 squarefeet.
I live in Santa Cruz California. I plan to use electric radiant with a toekick heater for those times I need extra heat.

I have read that hydronic is better - but for such a small space, I don't feel the extra space and complexity of hyrdronic is unwarranted.

The rest of the office will be heated by a minisplit.

I do have hydronic in the main house - but I feel I will lose a lot of heat running the hot water the 15 feet to the office.


Thanks in advance.


  • mattmia2
    mattmia2 Member Posts: 3,677
    Running hydronic piping 15' will lose little if you insulate it. A mini split would be a great way to heat and cool. As always heat loss and heat gain calculations are the first step.
  • Jamie Hall
    Jamie Hall Member Posts: 16,601
    Santa Cruz? The minisplit will be ample for the office, and do you even really need additional heat for the bathroom?
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • mattmia2
    mattmia2 Member Posts: 3,677
    There are mini splits that can use ductwork for distribution, maybe use that type to serve both rooms. AC likely is more of an issue than heat.
    EBEBRATT-Ed Member Posts: 9,688
    California just put some electric baseboards or an electric wall cabinet heater.
  • Intplm.
    Intplm. Member Posts: 1,331
    Look into a correctly sized Mini-Split system. You should be very happy with that considering your building size.
  • Dave H_2
    Dave H_2 Member Posts: 469
    I think the bigger question to ask is do you plan on AC in this space?

    If not, cost wise, I would go hydronic. its already there, a little pipe and element, a zone valve and a little wiring, not too shabby!

    If you are using a mini-split for the AC, well then that's a done deal cost-wise...
    Dave H
  • Lance
    Lance Member Posts: 168
    Dear Dave, I have done many of these before. For such a small space I recommend electric radiant for three reasons. 1) Independent zone and control 2) low expense installation. 3) Low cost in operation as usually a new space has superior insulation and a low heat load. 4) All my customers who did this were very happy with the results. Even if you choose a Heat pump for the office space, electric for the bath area is best where we size for 115% of the load. After all, this is a clothing optional room. and can also have its own control.
  • ethicalpaul
    ethicalpaul Member Posts: 3,089
    Mini split without hesitation. I'd never install resistive electric anywhere, but especially not in sunny California.
    1 pipe Peerless 63-03L in Cedar Grove, NJ, coal > oil > NG
  • hot_rod
    hot_rod Member Posts: 14,871
    how large is the office portion? If you want cooling and some dehumidification, a mini split may be the best option and small sizes are available. Heat only for that size bath I would look at electric radiant from an install and cost of operation. Depending on boiler type and size, possibly run a hydronic loop.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 2,221
    I have read that hydronic is better - but for such a small space, I don't feel the extra space and complexity of hyrdronic is unwarranted.

    Double negative is unclear. is this what you meant to say?

    I have read that hydronic is better - but for such a small space, I do feel the extra space and complexity of hyrdronic is warranted.

    and 15 feet is nothing! Unless you forgot to place a zero at the end... 150 ft is still just fine. that is what they make pipe insulation for.
    Edward Young
    Retired HVAC Contractor from So. Jersey Shore.
    Cleaned & services first oil heating system at age 16
  • bill_brooks
    bill_brooks Member Posts: 46
    when i built my house, hydronic radiant was a must. but...... even in the summer there are days when the
    bathrooms needed a bit of heat. for this reason, i chose electric radiant. not only for cost upfront, but to
    eliminate the need to fire my boiler for such small heat loads (60,75sqft.) i suppose i could have gone the
    wall heater route, but i didn't want to listen to the fan noise. the floor-sensing stats were a bit pricey but
    worth it.
    the turn-down of my boiler, plus it firing a 40gal. buffer tank would not cause short-cycling. but there it is. i'm happy with my design.
    BTW: firing the boiler into a buffer tank (rather than the heating zones) may seem unconventional. but
    in high demand cycles it keeps the on/off cycling to much longer periods. a positive scenario.