Where do I start?

buildhouse

Hi,

I'm building my own house in NJ. I'm a GC, we have our own plumber on salary, but have never done radiant heating before. I'm doing a slab on grade. I would like to do in slab radiant heating. First floor is 2ksqft with a 500sqft garage.

Where would I start to figure out how to design my system?

Thanks! 

Larry Weingarten

Hi, Do you have a heat loss calculation for the house? That would be the first step.

Yours, Larry

hot_rod

If you have the house plan, send it to one of the tubing manufacturers for a heat load and design. They may send it along to a wholesaler or rep for the area.

Have them do an cooling load also.

Don't consider radiant without a proper design.

Asheville area by chance? There are knowledgable wholesalers and hydronic/ steam guys down there.

Rehau, Uponor, Viega, Mr Pex, Watts, for pex brands. Their website would tell how to submit house plans to get a design done.

buildhouse

Thank you! I am in NJ. Will reach out to the PEX people.

buildhouse

hot_rod said:

If you have the house plan, send it to one of the tubing manufacturers for a heat load and design. They may send it along to a wholesaler or rep for the area. Have them do an cooling load also. Don't consider radiant without a proper design. Asheville area by chance? There are knowledgable wholesalers and hydronic/ steam guys down there. Rehau, Uponor, Viega, Mr Pex, Watts, for pex brands. Their website would tell how to submit house plans to get a design done.

I see a company Radiantec https://www.radiantec.com/ they seem to sell DIY kits etc. Have you ever heard of them? 

Hot_water_fan

Radiantec prefers a hot water heater over a boiler. 

Zman

buildhouse said:

hot_rod said:

If you have the house plan, send it to one of the tubing manufacturers for a heat load and design. They may send it along to a wholesaler or rep for the area.

Have them do an cooling load also.

Don't consider radiant without a proper design.

Asheville area by chance? There are knowledgable wholesalers and hydronic/ steam guys down there.

Rehau, Uponor, Viega, Mr Pex, Watts, for pex brands. Their website would tell how to submit house plans to get a design done.

I see a company Radiantec https://www.radiantec.com/ they seem to sell DIY kits etc. Have you ever heard of them? 

You can search them on this site and see feedback. I would recommend looking elsewhere.

Jamie Hall

buildhouse said:

hot_rod said:

If you have the house plan, send it to one of the tubing manufacturers for a heat load and design. They may send it along to a wholesaler or rep for the area.

Have them do an cooling load also.

Don't consider radiant without a proper design.

Asheville area by chance? There are knowledgable wholesalers and hydronic/ steam guys down there.

Rehau, Uponor, Viega, Mr Pex, Watts, for pex brands. Their website would tell how to submit house plans to get a design done.

I see a company Radiantec https://www.radiantec.com/ they seem to sell DIY kits etc. Have you ever heard of them? 

We've heard of them... usually from folks wondering how to fix the problems.

psb75

Do not use radiantec.

TAG

You need to do a proper heat load on the building and do a room by room. This is very important.

Make sure you understand how to insulate the slab and don't skimp or listen to people who say you don't have to do the whole thing .... you do.

I'm in the camp of a little more tubing is a good thing -- tubing is cheap and more of it will allow for lower water temp faster responce. I also like to zone my projects .. you only get one chance to do it correct and the small cost of over engineering is minor.

With good insulation and windows even a room with many windows can often be worked into a project and only use one water temp .... you want to use a boiler with outdoor reset (NJ has a lots of natural gas -- do you have it available? )

With zoning you can modulate a given room. With a high mass slab I find it's often nice to have a thermostat with a slab sensor .... Honeywell has one that can do both (room temp and slab) for about 80 dollars. In my last two projects I knew that a couple rooms most likely would need control so I bought a couple of those thermostats (they come with the sensor). In all the other rooms I just ran the wires to where one would go and I purchased the little floor sensor ($6) with out spending $80 for all the spaces. They get burred under the drywall.

I can't say enough about the Cross Manifolds -- a bit more up front cost but they are easy to set up and work great. My last two project were in NJ and PA -- both personal houses. Once the house is up and running you can tweak the system.

You have to start with that heat load

How are you doing the AC? Both of my houses have a mix of ducted and mini-splits. In the mid Atlantic with slab radiant you will find that having another heat source is better in the shoulder seasons .... on a cold late spring or early fall day the slab is just too slow when you just need to heat the space on a cool morning -- In New Jersey to get the rebates you will have to have a good heat pump. That will do it ... My house in PA only has propane and most of the time the heat pump is cheaper than using the furnace in the ducted system. NJ with natural gas -- the NG furnace is cheaper even with both states having .20 KW electric. The reason for having the furnace ... They are both partial use properties. I'm in NYC and depending on what is up I can fire up the furnace for a quick warm up and just have the radiant keeping the places in the low 60's. I also have zoned ducted system and I run them in the winter -- they really never turn on but they move the air aroudn and if you do have an odd room that may need more heat on a really cold day -- you have it available

Do some looking around and educate yourself .... don't skimp on tubing or insulation

buildhouse

TAG said:

You need to do a proper heat load on the building and do a room by room. This is very important. Make sure you understand how to insulate the slab and don't skimp or listen to people who say you don't have to do the whole thing .... you do. I'm in the camp of a little more tubing is a good thing -- tubing is cheap and more of it will allow for lower water temp faster responce. I also like to zone my projects .. you only get one chance to do it correct and the small cost of over engineering is minor. With good insulation and windows even a room with many windows can often be worked into a project and only use one water temp .... you want to use a boiler with outdoor reset (NJ has a lots of natural gas -- do you have it available? ) With zoning you can modulate a given room. With a high mass slab I find it's often nice to have a thermostat with a slab sensor .... Honeywell has one that can do both (room temp and slab) for about 80 dollars. In my last two projects I knew that a couple rooms most likely would need control so I bought a couple of those thermostats (they come with the sensor). In all the other rooms I just ran the wires to where one would go and I purchased the little floor sensor ($6) with out spending $80 for all the spaces. They get burred under the drywall. I can't say enough about the Cross Manifolds -- a bit more up front cost but they are easy to set up and work great. My last two project were in NJ and PA -- both personal houses. Once the house is up and running you can tweak the system. You have to start with that heat load How are you doing the AC? Both of my houses have a mix of ducted and mini-splits. In the mid Atlantic with slab radiant you will find that having another heat source is better in the shoulder seasons .... on a cold late spring or early fall day the slab is just too slow when you just need to heat the space on a cool morning -- In New Jersey to get the rebates you will have to have a good heat pump. That will do it ... My house in PA only has propane and most of the time the heat pump is cheaper than using the furnace in the ducted system. NJ with natural gas -- the NG furnace is cheaper even with both states having .20 KW electric. The reason for having the furnace ... They are both partial use properties. I'm in NYC and depending on what is up I can fire up the furnace for a quick warm up and just have the radiant keeping the places in the low 60's. I also have zoned ducted system and I run them in the winter -- they really never turn on but they move the air aroudn and if you do have an odd room that may need more heat on a really cold day -- you have it available Do some looking around and educate yourself .... don't skimp on tubing or insulation

I'm doing closed cell foam under the entire slab. I plan on putting in a standard HVAC system with a furnace, and so even if this doesn't get me all the way, I still would be covered.

The reason I'm thinking of doing this is because I am often cold. Even in my current house which was built 15 years ago, has spray foam in the attic, with a standard HVAC furnace, I often feel a bit chilly. It seems to my very uneducated self that a heated floor would make the house feel more cozy in a sense... 

HomerJSmith

Where do I start?

I find the best place to start is at the beginning. Sorry, me trying to be funny. I always wanted to use that saying.
Have a Happy Day even if it's raining, the SRI wants to do an audit, and your wife is filing for divorce.

MikeL_2

 The most comfortable high mass radiant systems I've been involved with include a modulating condensing boiler, multiple circuits of tubing under 250' as needed to satisfy the design, constant circulation, outdoor reset, and an adjustable / programable heating curve; no thermostat required.

JMWHVAC

You are on the right track to think floor heat should be a comfortable system. Nothing beats it for comfort, except maybe a wood stove!

Panheadsforever

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