Misc questions on radiant

Burgermeister_Meisterburger

All-

I am back.  Some may remember me from this thread.



<a href="http://www.heatinghelp.com/forum-thread/141907/Foreclosure-Questions-Checklist">http://www.heatinghelp.com/forum-thread/141907/Foreclosure-Questions-Checklist</a>



Well as I posted in the thread we did not get the home which was probably a blessing in disguise.  We have decided to instead build.  Quite a change.  We've recently purchased a wooded lot and are working through design plans with an architect and will be building a ranch house with an exposed basement out the back (north) and west side. 



Like most of us we have a budget and we are probably above it without any fancy stuff (custom cabinets, etc).  That said we really would like radiant vs forced air and we are trying to make the #s work but have some confusion after talking to some installers that I hope I can get some help with.

Before we went to the home show we met with a local Heating and Cooling shop that was recommended.  His suggestion was to do radiant in the basement with forced air/AC for the first floor.  His belief was that due to the thermal mass in the basement you will need a smaller Forced Air heating system and can use smaller ducts that we would already be running for AC.  When asked about using what type of concrete they would pour in the basement he stated just regular and not Gypcrete.  This is not an optimal system but he sees this quite often as somewhat of hybrid system.  My biggest concern is that he spoke of using water temps in the 130 range and not having to worry about if you ran it in the first floor and problems with hardwood buckling.  From what I've read on here this is old American thinking and not Euro thinking where one would use water at around (80deg?) under hardwoods.  This made me think this hybrid system would be the opposite of efficient with higher upfront costs than forced air but using forced air and getting no benefit of radiant on the first floor.  We will not be finishing the basement.



At the home show we found a guy who does radiant (almost exclusively) and he recommended using gypcrete in the basement and first floor.  He gave us a rough idea of cost, which we are using to try make fit into our budget.  Our biggest concern here is the gypcrete on the first floor and will that require extra supports beyond what he gave us as a ballpark.  Is this preferred over a warmboard type system from a radiant system?  We really liked him as had a passion, spoke about using Rehau and using a certain type of Pex (pex-al?) (Its red) vs standard pex that is cheaper but can breakdown.  He is a member of RPA and when I mentioned this website, he laughed and called you all a bunch of hippies.  ;)  I wonder if he overengineers systems.  Thoughts?



Lastly, we were walking by and saw a Geothermal guy who the radiant guy said to see.  (We can't afford geothermal).  As we talked to this guy, he saw that we had been talking to his friend and we told him that the frustrating part was that we will need a forced air AC system even if we do the full radiant for heat.  He told me that isn't the case anymore.  He was telling me that for the cost of geothermal that they could design the system to radiant cool the house (assume using the same pipes) in the summer with some simple add on equipment from Tekmar (tekmar 406 or 408?).  Is this true?  If so can I skip the Geo?

SWEI

where do we start?

Gypcrete and water do not mix.  I'd be hesitant to recommend it for a basement.



Coupling emitters (tubing) to the thermal mass greatly limits system responsiveness.  Low mass emitters allow the system to respond quickly when conditions dictate.



Maximum fluid temps will be under 120F in a properly designed system using floor, wall, or ceiling radiation.

Zman

Yikes!!

How important is AC? If you just need a few rooms for a few months a year, it would be easier to make it a stand alone system. Radiant cooling is possible. It is a fairly complex system to install and control.



I would keep it simple. Radiant heating on all floors with a mod/con boiler for sure. As SWEI mentioned, thermal mass is not always your friend. If it was my house, I would be looking at a  low mass low temp system. The upper levels would be joist track attached to the bottom of the plywood. In the basement level, I would take a hard look at low temp radiant panel heaters.This type of system will respond quickly and provide the greatest comfort.



I would find a contractor/designer that understands how to do a heatloss calculation and install a simple and efficient system.



I have had my suspicions about the hippies on this site for quite some time.It is good to learn I am not alone.



Carl

Mark Eatherton

Dave's not here man.... (Cheech and Chong circa 1970)

Boy, is HE badly mistaken ;-)



You have a LOT of options available in the design of your system. Radiant cooling is no longer a "concept". Off shelf controls are available for doing this from recognized manufacturers, and the Hong Kong airport has been running a radiant cooling system for quite some time now with no appreciable problems.



I prefer the use of Warmboard due to its inherent thermal efficiency. And yes, it can be used to base load (sensible) the AC requirements of the home.



I'd suggest you start at the RPA website, continue to educate yourself as to the different systems available, hire a competent designer to work with you and get what YOU want in the way of comfort and efficiency.



Remember, radiant is radiant regardless of whether it comes from the walls, ceiling, floors or windows. And it is the ONLY way to properly control the MRT, which drives the bus of human comfort.



Dave who???



Maybe he meant Hipsters, and not hippies ;-)



ME

Burgermeister_Meisterburger

thanks guys

Thanks for the fast response. 

SWEI - I maybe miss understood the radiant guy recommending gypcrete for the basement level.  I know that is what he wanted to do on the first floor, so if not probably just a regular poor after insulate and tie down the PEX.

Zman- I agree with the low temp system.  The radiant guy at the show who we liked spoke much of the fact that it would be a low temp system.  In fact he was so into heating by low temp water, building a sealed house to maximize gains that I was sure he posted on here.  (Thats a compliment to both you and him).  My wife is concerned by the idea of radiators as we have three young ones and concerns about resale value.  I plan to die in this house based on the amount of planning we have done.

What do you mean by 'joist track attached to the bottom of plywood?  Is that like a staple up system? 

Mark-  Thanks for the info.  I don't think Hong Kong is the only airport that uses radiant cooling.  I used to work at the Newark Airport and we used cooling as well.  Floors were concrete however.  When I have talked to local guys they tell me radiant cooling can't be done due to moisture buildup. 

Why warmboard over gypcrete?  Per a link from the RPA (I think?) that I saw it showed it as a lower R-value than Gypcrete.  Better than staple up but in new construction you wouldn't do that.  Is less labor to install and less cost for extra joists/coming back to pour the gyp offset the higher cost for the warmboard. 

I'll keep reading and probably asking questions.  Thanks hippies!

Burgermeister (mike)

Mark Eatherton

Response to Warmboard question...

Warmboard serves not only as the radiant heat emitter, but also the physical sub floor.



It does not require additional structural beefing up like the use of gyp or con crete will.



It's heat output for a given fluid temperature is far superior to most of the crete competitors.



Yes, the initial expense is going to be more than the crete alternatives, but the R.O.I. happens during operation. The fluid supply temperatures necessary to deliver good comfort conditions are SIGNIFICANTLY less than any of the other alternatives.



I will have it in my mountain home shortly, and will most probably power it with solar thermal with an air source heap pump for back up.



They have a series of video thermography comparisons on their site that are worth the watch.



http://www.warmboard.com/videos



It takes tubing at 6" O.C. to equal the surface output of their product at 12" O.C. with the same flow rate. That should tell you something....



And the people that you work with are all extremely nice and professional. They will generate a CAD drawing showing the exact placement of the Warmboard for the given zones, etc. I spoke to a GC who did his first Warmboard job on a 12,000 square foot home, and he said it definitely WON'T be his last... And he hasn't even experienced the comfort associated with its operation yet :-)



SUUUPERIOR RADIANT COMFORT that has to be experienced to be able to explain it.



Well worth the extra expenditure for comfort and efficiency, and they now have the R board (non structural) for doing walls, ceilings and countertops. Have you ever experienced the Morgue Effect that a cold marble or granite counter top gives you regardless of the time of the year? You can change that with R Board... Don't forget to leave a dead spot so you can put out ice cream without disastrous meltdowns... ;-)



ME

NRT_Rob

.

I like warmboard too. gypcrete is good but warmboard is more conductive and faster to respond.



if you want to do radiant cooling, however, that generally means you want tile floors, radiant ceilings, or supplemental fancoils in select areas. all depends on solar gain, really. You also need a supertight envelope and an ERV ventilator... still have fresh air ducts. but they are very small. Radiant cooling can be done but load calculations are a must and a designer who understands the limitations is a must.



second time today i've had to post this but we are doing it with a daikin altherma, air to water heat pump. like geo without the dirt work and massive upfront costs. can be very cost effective if it's displacing a boiler as well as a cooling compressor. not sure if there are trained installers in your area though, you'd need to check on that.

Burgermeister_Meisterburger

Thanks for that info

Guys thanks.  I think we will skip the radiant cooling at this time.  It just seems like the guys around here are not aware of it, have no experience and for the amount we use our AC it probably won't make sense at this time.

I appreciate the videos on warmboard.  The guy we liked at the home show who called y'all hippies was dismissive of warmboard as gypcrete was better and cheaper when I asked him directly if he used Warmboard.  Based on the videos its does conduct faster which has plenty of benefits. 

We are looking at 2 GCs neither who have any experience with warmboard but do have experience with geo (which we won't be doing) and radiant.  I'm surprised that the total cost of installation of warmboard is still more than gypcrete. I get that labor would be 50% more than install of a regular subfloor and the materials will be considerably higher than a standard subfloor but I'm surprised that the costs of extra support truss' extra runs for concrete company.  I'd rather pay more to the fairly unskilled guy installing a subfloor than what a plumber would charge me to run the Pex and tieing it down loose.  It seems like it should be cheaper upfront as labor is generally what I'm finding to be the expensive part. 

Lots to think about.  Will read more this weekend. Wife wants to spend time on kitchen layout tonight and in the morning.

Mark Eatherton

Race to the bottom...

People, especially heating contractors, are a funny bunch. They get into a groove (gypcrete for example) and they stay there, because "it works". When asked how it works, they haven't the foggiest idea, they just know that their customer has warm floors, and fairly happy people. I say FAIRLY happy, because gypcrete does have it's own set of "issues". For example, over heating, or over shoot is quite common. This is due to the thermal mass tendencies. It takes a considerable amount of time and energy to get this mass intensive system warmed up, and once the freight train of btu's is rolling, it takes it a LONG time to stop (putting out heat). As a consequence, the space takes a long time to recover from a deep set back, and a longer timer to disipate the heat it has built up in its mass. As a consequence, the room has a tendency to over shoot the room temperature, causing dis comfort due to over temp.



With Warmboard, all of those problems associated with a high mass system are completely eliminated. Granted, in an occasional use home, there is a lot of other mass that has to be accelerated in order to deliver full spectrum comfort in short order, but with Warmboard, or any equal low mass highly conductive heat emitter, very little fuel is spent in accelerating the emitter, and the surrounding mass starts warming almost immediately. And then when the brakes are applied, it stops on a dime, avoiding issues of overshoot, especially in this zones that will be seeing sunshine later in the day. Compounded heat input = discomfort due to over temp. The gyp dealer will tell you that its just the nature of the beast, and if you're uncomfortable, open some windows....



The gyp only dealer is also trying to offer the lowest price, because they fail to recognize the difference. Intelligent consumers like yourself that do their homework, and realize the value of these components will bypass him and go with a more intelligent, more expensive system/design.



I have NEVER been the lowest bidder. In fact, if I were the lowest bidder, I'd probably worry about what it was that I forgot to put into the bid, like the tubing, or manifolds, or heat source...



As for labor, the actual placement of the Warmboard is done by carpenters. The radiant contractor still has to do the tube into the grooves, but it goes REALLY fast, saving on the more expensive labor. It does require a fair amount of significant fore thought, but that's what the manufacturer provides the CAD support for. And as with ALL radiant heat emitters, you MUST place insulation below the floors to control the directional flow of energy.



The factory generated blue prints show the GC EXACTLY where to place the different boards (there are only 3 different types) and comes with groove alignment tools to make their job easier. It is all tongue and groove, and goes together just like a regular T&G floor would.



One word of caution, and this is always overlooked. The tubing is placed, then the internal non support walls are put up, so you have tubing exposed to potential damage. It is strongly recommended that the floor and tubing get covered with 1/4" plywood to provide protection against inadvertent damage during the balance of construction. A minor up charge for the increase in efficiency and comfort...



If you build your home right, your need for AC could be fairly insignificant.



It pays to do your homework in advance...



ME

Jack

Cooling

I would not even consider the geothermal. You can put in mini-split heat pumps and operate at a cost very close to the geothermal for far less dough. This is absolutely worth a look. The best brands are Fujitsu, Mitsubishi. Where are you located?

duffy_4

Warm board

Couldn't agree with mark anymore,built my home in Chicago five years ago,two story brick,approx 2200 square ft,I looked at all the options and went with warm board initial upfront costs ,but superior operational costs ,comfort,tubing installation ,ease of zoning and the total cost per suare foot is comparable to other installation methods when you total all costs and labor.have done several warm board homes for clients since and all are extremely pleased with results.

duffy_4

Warm board

Couldn't agree with mark anymore,built my home in Chicago five years ago,two story brick,approx 2200 square ft,I looked at all the options and went with warm board initial upfront costs ,but superior operational costs ,comfort,tubing installation ,ease of zoning and the total cost per suare foot is comparable to other installation methods when you total all costs and labor.have done several warm board homes for clients since and all are extremely pleased with results.

duffy_4

Warm board

Couldn't agree with mark anymore,built my home in Chicago five years ago,two story brick,approx 2200 square ft,I looked at all the options and went with warm board initial upfront costs ,but superior operational costs ,comfort,tubing installation ,ease of zoning and the total cost per suare foot is comparable to other installation methods when you total all costs and labor.have done several warm board homes for clients since and all are extremely pleased with results.

duffy_4

Warm board

Couldn't agree with mark anymore,built my home in Chicago five years ago,two story brick,approx 2200 square ft,I looked at all the options and went with warm board initial upfront costs ,but superior operational costs ,comfort,tubing installation ,ease of zoning and the total cost per suare foot is comparable to other installation methods when you total all costs and labor.have done several warm board homes for clients since and all are extremely pleased with results.

duffy_4

Posts

Sorry for multiple posts musta hit button few times don't know how to delete

Burgermeister_Meisterburger

Duffy you must like it.

Thanks Mark-

Duffy likes it so much he posted it 5 times!

Shared the videos from Warmboard with my wife over the weekend.  Before we thought the thermal mass of the gypcrete was a positive, kinda like a Finnish Tulikivi fireplace (my grandparents had a Norwegian version in their house - 80% as good at 1/3rd the cost (ha- Making fun of the fins was my grandfathers pasttime.  Was upset when the Norwegian and Swedish lutheran churches merged).  The good news so far with the wife and I as we go through our budget on the home is we both agree that the key is comfort as the #2 most important thing.  #1 is storage.  Its not a big house at just under 2,000 sq ft ranch but I think the house is sized well as we've spent a long time on it. 

Our two GCs that we are considering were not the cheapest but fair and they demand quality from their subs.  Going to keep calling around to find some heating and cooling guys who have used warmboard around here.  They could recommend an installer if need be. 



Also, the bedrooms are all going to be carpet.  Either solution (gyp or warmboard) would be low temps 80 degrees so it shouldn't matter as I know carpet requires a certain pad for radiant.  If the bedrooms all have carpet would it make more sense from an efficiency standpoint to do rads or woudl maybe warmboard on the ceiling something like that as I think as much as you try you will lose a bunch in the carpet.



Last question, I grew up in a house with HW baseboards.  Most people I talk to about them don't like the look and the fact that they take up space on walls where furniture could go.  If radiant ceilings work why not HW baseboards on the ceilings and use some sort of molding to somewhat disguise it.  Am I crazy?



Jack - just outside of Madison, WI.  Wife is afraid of noise of mini-split system but hasn't seen the newer stuff yet. 

SWEI

baseboard

Works primarily by convection.  Putting it on the ceiling might work (somewhat) for cooling, but would be counterproductive for heating.



Warm walls (lower half) or ceilings work quite well.

Mark Eatherton

Someone beat you to the idea already...

A someone named Edwards Engineering has a "Valance" heating and cooling baseboard that is mounted up near the ceiling. If you thought base board was ugly, wait until you see this stuff. It's the poster boy of atrocious... U G L Y. http://www.edwardsvalance.com



And as for comfort, nada chance. The ceiling air temperatures run about 120 degrees F in order to maintain 70 at the floor. With this system, your hair really does feel like it might catch on fire... ;-)



When you run chilled water through it for cooling, the condensate drips off of the fin tube sections into a trough. The trough has a tendency to be an excellent growing ground for mold and other moist seeking bacterium. (STINKY)



I know they still make it, but I would not suggest anyone consider using it.



For a bed room, radiant ceilings make perfect sense. You sleep on top of the bed, so having the radiant on the ceiling means you can (and most probably will) sleep without any blankets.



I have radiant ceilings in 1/2 of my mountain home, and I love it. Granted, warm floors are nice, but they are not the be all/end all.



I've often wondered out loud where we as an industry would be if Richard Trethewey had walked on to the set of This Old House and said "We're going to do a radiant ceiling today" instead of what he really said that launched the current RFH revolution.



I don't know of ANY customers that I have that regret the decision to go with Warmboard, but I have MANY customers who are really disappointed in the performance of their gypcrete... It powders and groves in high traffic areas. If it gets wet, it turns back to a mush and doesn't re-harden and must be removed and replaced. It seems like it takes F O R E V E R to expel its moisture so that finished products (wood floors) can be applied over the top of it.



I think it was a great idea who's time has come, and gone. There are much more efficient methods of doing RFH, and I have around 250,000 square feet of gyp and cement based systems out there... And close to 50,000 sq. ft. of Warmboard jobs.



ME

Ironman

WarmBoard + Mini Splits

We install Mini splits all the time and you can't even tell they're running until the fan goes to max. which normally doesn't happen if you leave the settings alone. Even then, they are far quieter than ducted and their ability to de-humidify coupled with their higher efficiency puts them far ahead of their noisy counterparts.



And I totally agree with Mark that WarmBoard is the way to go. If I were building a new house for myself, I'd go with WarmBoard and Mini splits and some radiant cooling.



Take a look at Daikin's Altherma with some ductless wall units as a possible source for heating and cooling."NRT-Rob" at Northeast Radiant Technology Has been using one to heat their shop in Maine and tracking the energy usage. The numbers are amazing. The system can provide warm water for space heating, domestic and chilled water for cooling. The have ductless wall units that run off of the chilled water.

Burgermeister_Meisterburger

Thanks Mark

We had our final(ish) meeting with our architect yesterday so he's making everying 1/4 inch so we can get docs out to get going on bids.    Looking at our plan more it would be very easy to do radiant floors in the main area as the carpeted areas (bedrooms) are all together.  I'll call Warmboard and see if they can recommend someone in the area especially if we could do radiant in the ceiling in the bedroom areas.



I figured after I posted about the hotwater system on the ceiling that it had to be that the water temp was too hot and my hair would catch on fire.  Previously I never really thought about my mom's old place until our current residence which is forced air in a drafty house.  I hate it.  Going home I realized mom has furniture blocking all the baseboards in some of the rooms.  Figured there had to be a better way.  Wish there was more acceptance of new panel rads in the US.  My wife won't consider them with kids and our realtor said that for many buyers its a won't consider.

SWEI

panel rads

If you size them appropriately, water temps can be kept low.

Burgermeister_Meisterburger

Panel Rads

I assume (big ?) that panel rads are cheaper than radiant in flooras installation would be cheaper they may be a good addition in houses like ours.  We have friends who are building and looked at radiant but even if you think total cost of ownership is cheaper in say 7-10 years and more comfortable its hard to pay for it upfront.  Every bank around here requires 20% down for new construction and then the appropriate income ratios, etc yet they don't look at the affordability as your operating costs are less in the future.  Not sure how the industry can overcome that. 

Two last questions for a while.

1.  The guy who recommended lightweight concrete over warmboard is an RPA member and appears to be the only one in the area.  He also called you a bunch of hippies .  Upon closer inspection there appears to be an former RPA member who won an award in 2011 but no longer appears to be in the RPA.  While my wife secretly likes me asking questions here she will always defer to a pro in person.  With that in mind what questions should I ask him with the wife present?

Especially now that I think I have a second person to contact. 



2.  Can you tie in a panel rad in the bathroom for a towel rack with radiant?  Does it require its own run?  Wife loves them and I'd like to get them into the design without her noticing working with whomever I choose so that she is unaware until the very end. 

Burgermeister_Meisterburger

Panel Rads

I assume (big ?) that panel rads are cheaper than radiant in flooras installation would be cheaper they may be a good addition in houses like ours.  We have friends who are building and looked at radiant but even if you think total cost of ownership is cheaper in say 7-10 years and more comfortable its hard to pay for it upfront.  Every bank around here requires 20% down for new construction and then the appropriate income ratios, etc yet they don't look at the affordability as your operating costs are less in the future.  Not sure how the industry can overcome that. 

Two last questions for a while.

1.  The guy who recommended lightweight concrete over warmboard is an RPA member and appears to be the only one in the area.  He also called you a bunch of hippies .  Upon closer inspection there appears to be an former RPA member who won an award in 2011 but no longer appears to be in the RPA.  While my wife secretly likes me asking questions here she will always defer to a pro in person.  With that in mind what questions should I ask him with the wife present?

Especially now that I think I have a second person to contact. 



2. Has anyone used BEopt?  Useful or not?  Friend recommended it as it helped him weigh building options. 

3.  Read on a different forum a post by NRT Rob (from 2010?) who discusses the three options for radiant (ceiling, some, floor) and said that ceiling was the least comfortable of the three.  Is that old knowledge or would radiant in lower walls make more sense. 

SWEI

panel radiators, towel warmers, and RFH

"Cheaper than" is highly job dependent.  If you're retrofitting an existing house, probably.  If it's a new build and you're using WarmBoard as the subfloor, maybe.  They do take up some wall space which limits your options for furniture placement.



RPA membership used to be a given for pretty much anyone in this industry who was serious.  The decline of the RPA over the past few years made it less attractive to many of us, though ME assures us things are tilting back the other way now.



Hydronic towel warmers are a real treat in bathrooms and can be piped a number of ways.  Separately from other zones if they are the only radiation in the room, with or without a zone valve or TRV.  In series with a floor loop if  the other system emitters were designed for higher temps.  Which works best really depends on the particulars of the system and the location (heat loss) of the bathroom.

NRT_Rob

it is true

that radiant ceiling is not AS comfortable as radiant floor in heating mode. however it is also true that it is still more comfortable than baseboard or forced air of any variety.



I would put it higher than panel rads in most cases as well. though if you do have higher temperature radiators and you can stand right up on top of them, that can be nice. I like to sit very close to ragingly hot woodstoves. but for the overall comfort of the room, any full radiant surface will beat a smaller panel radiator.



I tend to avoid radiant walls because of furniture and puncture issues. I prefer ceilings for those reasons. also installation is easier.

Burgermeister_Meisterburger

Thanks rob And swei

Thanks for the info on rpa. Seemed strange that a local company that won an award in 2011 isn't a current member.



Rob, appreciate the detailed response. Having never seen a radiant ceiling before doing so would take a leap of faith. In today's marketplace is warmboard basically the only way to do radiant in the ceiling?

SWEI

radiant walls

work OK using the lower four feet of a wall.  Make sure to specify a chair rail mounted above the highest tube location.  Educate the occupants -- nobody hangs pictures that low anyway.



WarmBoard and Roth Panel have exceptional efficiency.  There are a number of highly engineered architectural ceiling systems which perform even better, but the costs are staggering.

NRT_Rob

not at all

if you're cooling, I would stick with warmboard R.



if you're just heating plates and strapping work fine too. plates against the drywall.