New individual heating in apt units
Hi all,
Does anyone have an opinion on installing individual heat in apartments / condos? We are working on a 20-unit, 4-story wood-frame apt building that has been damaged in a fire. The building has been stripped down to the studs. The existing heat is provided by radiators (old-timey cast-iron with big decorated fins), powered by an ancient gas boiler in the basement.
Since the structure is down to the studs it seems a good time to replace the old central system wich individual heat. Gas seems best because (a) all apts already have individual gas meters, and (b) tenants hate baseboard electric.
It makes sense to switch to individual water heaters as well.
The units are mostly one-bedrooms, about 600 sq ft. The building will be insulated and dbl-pane windows installed. We are in Western Oregon so winters are pretty mild.
Any unit(s) we select will have to be installable in very tight quarters (the plan is to house them in very small utility closets), and, I assume, direct-vent.
We’ve done some research and these are the possible solutions we came up with:
1. Conventional forced-air furnaces and water heaters;
2. Combo boiler / water heater units that would use the existing radiators with new piping;
3. Combo boiler / water heater units, but with radiant floor heat. The heat elements could be installed fairly easily from below since all ceilings have been taken down.
For 2 and 3, the other question what kind of combo boiler / water heater? We saw the water heater-based kind (Bradford White), and the boiler-based kind (Weil-McLane Ultra, Lockinvar Knight, HT Munchkin, etc.).
Net cost is a big consideration of course, but so are comfort and energy conservation. Any feedback will be great! Thank you very much.
Replies
I'm voting for the most comfort at reasonable install cost and perhaps lowest long term heating bills.
Go with the in floor heat, and a small 50K BTU modulating boiler with an indirect WH and a prioritized domestic hot water controller.
If you are carful with the design and lay out you in floor with each rooms/zones heatloss in mind you can have a very nice system with a very basic control/zone system.
In 600 sqft I would try for 1 or 2 zones max. Use balancing valves to fine tune the loops within the zones.
Pick your boiler based on what is available and has a good service and support in your area.
Spend time on getting the insulation portion of the project right while you have the walls opened up.
I prefer wetblown cellulose, best performance for your dollar in most situations.
Spray foam is a really good product and can be used in difficult situations but seems to be expensive for large jobs.
If the situation was right, I would also consider a single modulating boiler set up. Then include heat in the rent. Balance the cost out so the rent is lower than the rent and heat would have been in the coldest months for an average rental in your area then bank the difference all year and pay for the extra insulation and high efficiency heating system.
Value and comfort added for the tenants.
Hot water would/could be on demand or standard heaters or a large indirect if you wanted
to include hot water too.
Good luck,
Garett
I'm just north of ya.
All of my jobs these days are central hot water
Individual heat pumps for the units using a central chiller.
When asked why is there four engines on a 747------ "cause we couldn't fit six" a Boeing engineer
Thank you for your replies, you all make good points. I should have said that down the road the building will probably be sold as condos. In that context, individual systems that are billed directly to the condo owners make a lot of sense, and would also help greatly reduce HOA dues.
If you guys had to make a choice between individual forced air furnaces plus water heaters, and combo boilers reusing the existing radiators, which would you go for, and how would the two solutions compare as far as installation costs?
Mini-split heat pumps sound interesting, as a matter of fact I remember seeing those everywhere in Asia, I just didn't realize they were available in the US because I've never seen one here. The 'free' AC is a big plus. Does anyone have experience installing / running those? Are they quiet? And how do their operating costs compare with a 90%+ gas heat source?
Thanks
the problem you could run into with electric... is the total load... I would guess a 125amp service min to each unit?
the mini splits are show'n up everywhere... i've used a few a/c only units... check out ebay there are alot of supply houses that sell dirrect thru ebay...
for 600sf units... i'd think the short 28gal water heaters would be fine... electric so u don't have to deal with a vent... they will fit in a pretty small space even under counter... or space above a closet.... $200 ea...
mini split units... 1 ton with lines you are still under $1k think they require a 3" hole in the wall... think the heat cool units come with a heat strip back-up for when it's real cold..... now just add a combo washer/dryer vented or ventless & ur set....
p
i don't know your temp swings... but do you guys use ac there? if so I'd look at maybe the ductless heat pumps... 600sf 1 ton units @ under 1k each and the install is fast & cheap... but that doesn't help with your hot water...
p
If you will have ac, take a look at having an extra large hot water tank that also feeds a heat exchanger on the air handler for heat. We have that in our apt./condo complex and it actually works pretty well. The extra hot water capacity is really nice for those days when the family comes to visit and 6 people are taking showers one after the other.
It cuts down on maintenance and cost over two separate self contained units.
Beer was created so carpenters wouldn't rule the world.