Radiant in floor heat (concrete slab)

[Stuntman Autoworks]

I'm going to build a large shop and house combo and I'm thinking of heating it with a radiant in floor system. Does anybody have any firsthand experience with one of these systems?

 

[Chris_Keziah]

@CasterTroy ?

 

[fourtrax]

I installed one in mine.

 

[Stuntman Autoworks]

I installed one in mine.

How does it do? Expensive to operate? Do you need other heat sources also or is it good by itself? Feel free to message me if you want.

 

[fourtrax]

good question. I installed it earlier this year when i built the garage. haven't needed to fire it up yet.

 

[Stuntman Autoworks]

good question. I installed it earlier this year when i built the garage. haven't needed to fire it up yet.

Electric instant hot water? How expensive is it to install? Did you install yourself or did you have it installed?

 

[skyhighZJ]

Had it in the house I used to own in Northern Michigan. The house had a full basement with poured concrete walls 3/4 sunk with a walk out back wall. In the dead of winter the house furnace (“upstairs”) would run about 1/4-1/2 the time if I was running the water heater to heat the floor. Ran a conventional propane WH. Being a closed system the elements in the heater never got crusty. I had a company come out every fall and check the system and the water. Cost about $150 for the service check up. System was probably 5 yrs old when I bought it. I owned it for 13 yrs. never had a single issue.

edit: it is really nice cause it’s basically dust free heat cause there is no “blower” to move the heat.

 

[fourtrax]

did it myself. The shop is 28x40 have about 6" of insulation in the walls and r13 on the ceiling. so far haven't needed the heat. have about $550 in the pex and manifold and about $2k to finish up with the panel and 10k heater.

used this for a guide ended up using the "heat sink" slab design
The Slab on Grade Installation | | DIY Radiant Floor Heating | Radiant Floor Company


https://www.menards.com/main/plumbi...4726-c-8521.htm?tid=511941231281877254&ipos=2
https://www.menards.com/main/plumbi...ectric-microboiler/sh3-10/p-1444433731612.htm
Radiant Floor Heating | PEX Piping | Infloor Heat | BlueRidge Company

 

[CasterTroy]

@CasterTroy ?

I had neither the time, nor first hand experience to do this in my combo shop/house. I've designed a few layouts for rich folks, and for community college sidewalks, but nothing specific. Just pointed to a vendor and used a book spec.

I WANTED TO use this in my place...I wanted too pretty bad. Even had plans to build a water stove shed a few feet away to house the wood water stove to heat the floor system. Wood because I have SO MUCH of it, and no access to gas. And Propane and or electric would have too long a payback. Wood/Solar was about the best payback when you did a long term cost analysis. But, then I started thinking about my age, and how in 15 yrs do I want to still be splitting wood?
Then there was the installation of the underfloor system. If I did it myself, the cost would be minimal. But TIME wasn't something I had a lot of. So I got a few quotes. When I plugged it into my long term payback calculations, a pair of wall mounted split systems running full out cost less.

In fact, I had to turn my heat DOWN this weekend because I was sweating out there. And my floors aren't turrible cold.

 

[fourtrax]

Mini split would definitely be nice, I might do that for air conditioning in the summer. But it' will be nice to work on a warm floor not have to worry about any fans blowing stuff around.

 

[Loganwayne]

i wouldnt do it unless i had it hooked up to an outdoor furnace.

 

[jeepinmatt]

I had neither the time, nor first hand experience to do this in my combo shop/house. I've designed a few layouts for rich folks, and for community college sidewalks, but nothing specific. Just pointed to a vendor and used a book spec.

I WANTED TO use this in my place...I wanted too pretty bad. Even had plans to build a water stove shed a few feet away to house the wood water stove to heat the floor system. Wood because I have SO MUCH of it, and no access to gas. And Propane and or electric would have too long a payback. Wood/Solar was about the best payback when you did a long term cost analysis. But, then I started thinking about my age, and how in 15 yrs do I want to still be splitting wood?
Then there was the installation of the underfloor system. If I did it myself, the cost would be minimal. But TIME wasn't something I had a lot of. So I got a few quotes. When I plugged it into my long term payback calculations, a pair of wall mounted split systems running full out cost less.

In fact, I had to turn my heat DOWN this weekend because I was sweating out there. And my floors aren't turrible cold.

This was a lot of my thought process and why we didn't do it in our house. I thought about doing it in the master bath, but my wife actually LIKES cold floors on her feet, and I was sure there would be rugs and bathmats and whatnot, and I was correct.

We have a wood stove in the basement, so when its going to be below freezing at night for a couple days, I'll crank it up. Our highest power bills have been about $130 for ~4000sqft total enclosed space (plus attic), and that is 100% electric, with a wife and 2 kids that are home all day, 7 days a week. I guess the purpose of that is to say that spray foam insulation is the way to go in combination with whatever type of heating system you go with. I think the lowest total cost of install and ownership would be a sprayfoamed structure with a few strategically placed mini-splits, and some solar supplement.

 

[Stuntman Autoworks]

I had neither the time, nor first hand experience to do this in my combo shop/house. I've designed a few layouts for rich folks, and for community college sidewalks, but nothing specific. Just pointed to a vendor and used a book spec.

I WANTED TO use this in my place...I wanted too pretty bad. Even had plans to build a water stove shed a few feet away to house the wood water stove to heat the floor system. Wood because I have SO MUCH of it, and no access to gas. And Propane and or electric would have too long a payback. Wood/Solar was about the best payback when you did a long term cost analysis. But, then I started thinking about my age, and how in 15 yrs do I want to still be splitting wood?
Then there was the installation of the underfloor system. If I did it myself, the cost would be minimal. But TIME wasn't something I had a lot of. So I got a few quotes. When I plugged it into my long term payback calculations, a pair of wall mounted split systems running full out cost less.

In fact, I had to turn my heat DOWN this weekend because I was sweating out there. And my floors aren't turrible cold.

This was a lot of my thought process and why we didn't do it in our house. I thought about doing it in the master bath, but my wife actually LIKES cold floors on her feet, and I was sure there would be rugs and bathmats and whatnot, and I was correct.

We have a wood stove in the basement, so when its going to be below freezing at night for a couple days, I'll crank it up. Our highest power bills have been about $130 for ~4000sqft total enclosed space (plus attic), and that is 100% electric, with a wife and 2 kids that are home all day, 7 days a week. I guess the purpose of that is to say that spray foam insulation is the way to go in combination with whatever type of heating system you go with. I think the lowest total cost of install and ownership would be a sprayfoamed structure with a few strategically placed mini-splits, and some solar supplement.

Would the minisplits still work with 8,000 sq/ft of shop and home space? 80x80 shop 20x80 home

 

[rcalexander105]

Would the minisplits still work with 8,000 sq/ft of shop and home space? 80x80 shop 20x80 home

80x100 Bardo-life

 

[jeepinmatt]

Would the minisplits still work with 8,000 sq/ft of shop and home space? 80x80 shop 20x80 home

Well, I guess you did say "large shop", but I was figuring that meant 3000sqft or something. I guess that depends on what level of "comfort" you want. I don't know that the mini-splits would move enough air to properly condition 8000sqft in a consistent fashion.

 

[CasterTroy]

Would the minisplits still work with 8,000 sq/ft of shop and home space? 80x80 shop 20x80 home

No, especially assuming at least a 14ft ceiling, and if no ceiling, assuming an 18ft "peak"

At that size I would consider a 15 ton rooftop mounted on a slab, pantleg up exterior wall and trunk line run down center of building.

12.5 ton MAY work if no windows, and no people load. But given garage doors and recovery 15 ton would likely be required. Prefer Gaspack, but if all electric, still can be done

Split system or actually a VRF system for residential where you have one outdoor unit and multiple indoor units.

Just my opinion

 

[rcalexander105]

Just my opinion

Not like you get paid to do this kinda stuff or anything

 

[CasterTroy]

Not like you get paid to do this kinda stuff or anything

What idiot would do that?

 

[Stuntman Autoworks]

Well, I guess you did say "large shop", but I was figuring that meant 3000sqft or something. I guess that depends on what level of "comfort" you want. I don't know that the mini-splits would move enough air to properly condition 8000sqft in a consistent fashion.

Shop just needs the chill knocked off I can work in 45 or 50 degree weather very comfortably but 30 degrees is different. The 1600 sqft living area would need to be just like any other home.

 

[Stuntman Autoworks]

The reason I was considering the in floor heat is because in a shop you are usually close to the floor working and if the floor is warm when you lay on it then everything seems much better even if the air temp isn't as warm as it could possibly be.

 

[Stuntman Autoworks]

No, especially assuming at least a 14ft ceiling, and if no ceiling, assuming an 18ft "peak"

At that size I would consider a 15 ton rooftop mounted on a slab, pantleg up exterior wall and trunk line run down center of building.

12.5 ton MAY work if no windows, and no people load. But given garage doors and recovery 15 ton would likely be required. Prefer Gaspack, but if all electric, still can be done

Split system or actually a VRF system for residential where you have one outdoor unit and multiple indoor units.

Just my opinion

Yes 14ft door and no ceiling but there will be some mezzanines built in different areas. Right now I don't know if I want to spend the money to air condition the shop. I figure the doors open with a large exhaust fan pulling a breeze through would be sufficient.

 

[CasterTroy]

The reason I was considering the in floor heat is because in a shop you are usually close to the floor working and if the floor is warm when you lay on it then everything seems much better even if the air temp isn't as warm as it could possibly be.

Without a doubt it's the BEST solution for what you are after. Economically though, I have found that unless you do a lot of it yourself, your cost will be in line with conditioning the space. This has just been my experiences in my area. YMMV depending on the experience of local installers

 

[Stuntman Autoworks]

Without a doubt it's the BEST solution for what you are after. Economically though, I have found that unless you do a lot of it yourself, your cost will be in line with conditioning the space

I feel comfortable doing the install and all the wiring and plumbing if it is the best option but I also don't know all the different systems out there like you and others do.

 

[Stuntman Autoworks]

Without a doubt it's the BEST solution for what you are after. Economically though, I have found that unless you do a lot of it yourself, your cost will be in line with conditioning the space. This has just been my experiences in my area. YMMV depending on the experience of local installers

YMMV?

 

[CasterTroy]

Your
Mileage
May
Vary

I feel comfortable doing the install and all the wiring and plumbing if it is the best option but I also don't know all the different systems out there like you and others do.

We get hit with vendors pushing "the new hotness" every few months. "SOLAR" was all the rage then heat pump, then VRF, then solar AGAIN, then GAS.

At the end of the day, after seeing all I've seen....SIMPLICITY and the ability to go to ACR on saturday and buy an off the shelf item that's widely available so I can get back online in hours, not days, trumps anything that may or may not be able to be controlled to the Nth degree from my phone.

I say all that to ask: WHEN this system breaks...and it's a mechanical system, it WILL break......what are you willing to do to fix it, and or replace it with something else?

MY big thing was; I was putting a lot of faith in a water furnace, and underground piping. The pumps...they can be replaced...but pipe failure under slab, or the water stove developing a leak....that would be a problem. $1200 wall mounted split systems and/or commercial rooftop units mounted on a slab are like big screen TV's ..they break, replace within hours.