Staple up radiant advice

bombaloo

I will be making some significant changes to my heating and cooling in my house in the coming years. In short, the steam radiators and high velocity spacepak are going to go. I know I know some people won’t forgive me for getting rid of the steam but for many reasons it is not working out in the house, one of which was it was never properly incorporated into an addition on the house and the house will be getting a second addition. 

Anyway the plan is the top floor would get a ducted inverter heat pump air handler in the attic. Mitsubishi hyper heat to handle heating and cooling. Would add a ERV through the ductwork as well. The first floor would get a couple ductless units that would be used for cooling and shoulder season heating. The cold season heating would be underfloor hydronic heating (oil boiler).  Currently the basement has a finished ceiling with no insulation in it. The current floor is a 100 year old fir floor with a T&G subfloor. There was some talk about removing the entire floor and putting down radiant panels like warmboard and putting down new engineered oak. However I’d prefer not to do that and keep my original floor and instead remove basement ceiling, spray foam any exposed rim joists and do the best possible staple up heating system there is and put any necessary insulation and refinish the ceiling. However the new addition could get a warm board type panel. Does this plan sound right? Mixing staple up in one section of the house with over the subfloor radiant panels in the new part of the home? I guess I would need 2 separate loops where the staple up temp would be 110 or so and the above the subfloor temp would be more like 90 to get a 75 degree floor. Anyone done anything like that? Or should I keep it consistent and put the heating under the plywood subfloor in the new addition? Also how do you place a floor temperature sensor on an existing floor? And do these thermostats come with outdoor temperature sensors to prevent the floor from heating up when it is relatively warm outside?

in addition to all this i plan to add an wood fire insert into my fireplace to use for emergency backup heat or just nice radiant ambiance type heat. I also plan to place a Aprilaire ductless steam humidifier on the first floor. 

Please give me any advice on this master plan. 

Mad Dog_2

Before you make any decisions, you can easily pull off a Hydronic zone off the Steam Boiler or a Small dedicated Wall Hung boiler which you can do Radiant Staple up, whatever.   Mad Dog 🐕 

bombaloo

Mad Dog_2 said:

Before you make any decisions, you can easily pull off a Hydronic zone off the Steam Boiler or a Small dedicated Wall Hung boiler which you can do Radiant Staple up, whatever.   Mad Dog 🐕 

Well I want to completely do away with the radiators to reclaim tons of floor space. Plus I had my system analyzed by an expert here and my 5 section boiler was grossly oversized for the amount of radiators I had. It’s a big beast that makes tons of rumbling noise. I’d rather have a much smaller and more efficient hot water boiler matched perfectly to the system. I have DHW through gas but the moratorium here is strict so unfortunately I can’t combine them. 

Ironman

The first thing that you need to do is an accurate Manual J heat loss calculation to determine if a radiant floor can supply sufficient heat to a 100 year old house. There’s a good possibility that it won’t. Especially with the sub and finished floor that you have.

Proper design is the key to getting a radiant floor that performs properly.

I highly recommend that you contact Rich McGrath @Rich_49 or one of the other designers on here for assistance.

bombaloo

Ironman said:

The first thing that you need to do is an accurate Manual J heat loss calculation to determine if a radiant floor can supply sufficient heat to a 100 year old house. There’s a good possibility that it won’t. Especially with the sub and finished floor that you have.

Proper design is the key to getting a radiant floor that performs properly.

I highly recommend that you contact Rich McGrath @Rich_49 or one of the other designers on here for assistance.

Yes the people I end up hiring I will make sure they do that type of analysis however the home has been kept in very good condition and I feel it’s quite tight. Double pane windows, exterior walls were spray foamed. Attic roof has closed cell. Boiler doesn’t have to run much in the day to keep a 68 degree temperature when it’s pretty cold out. And a heat pump would heat the upstairs bedrooms so really the hydronic would just be for the first floor but yes the age and condition  of the subfloor and floor worries me 

bombaloo

Has anyone personally put staple up radiant plates on a pure wood TG subfloor?

ethicalpaul

I have put them up on a pure wood 3/4" floor (in my house, there are no subfloors at all--there is old-growth pine planks nailed directly to the joists). Mine is for comfort only, not overall heating--I use steam for that! Be very careful in a decision to remove it.

It works great, but look at the extruded aluminum screwed-in plates (I used Uponor), not the thin staple up stuff IMO.

Your subfloor will slow your heat transfer. You should do a heat loss calculation to see if it can keep up as you were already advised.

bombaloo

ethicalpaul said:

I have put them up on a pure wood 3/4" floor (in my house, there are no subfloors at all--there is old-growth pine planks nailed directly to the joists). Mine is for comfort only, not overall heating--I use steam for that! Be very careful in a decision to remove it. It works great, but look at the extruded aluminum screwed-in plates (I used Uponor), not the thin staple up stuff IMO. Your subfloor will slow your heat transfer. You should do a heat loss calculation to see if it can keep up as you were already advised.

I think a happy medium would to use flat panel hot water radiators if I needed to use something else to supplement the heated floors. The steam is definitely going to have to be removed though. I’d like to one day in the future have the hydronic run by an air to water heat pump when they become more mainstream. Steam where I am is conpletely out as a heating system and rather have hydronic either radiant floors or panel radiators 

JMWHVAC

We have put stapleup under all types of floor with & without aluminum. The only thing that matters is the thickness (R-valve) of your total floor and the BTU per square foot (heat loss) that you need. An old house you MUST KNOW how many layers & of what, the floor consists of. With those two data points you can determine what you can do & what you want to do. If you just throw tubing under floor without knowing how many layers, you may be disappointed.