New baseboard heating install- Can I bury the elements into the wall?

shamu1023

I'm wondering if it's okay to install baseboard elements into the wall, rather than standard enclosures (with insulation, and air gaps of course)?
I'm re-doing my basement. I have existing baseboard, but they are all torn up, so I'm replacing the elements.

So, the idea was to "hide" them in the wall, rather than installing them on the exterior of the wall.
The thought is to use 2x6s instead of 2x4s for the wall. Using the 2x6s, create a 6x6" cavity for the heat elements.
Then use mylar foil to wrap the inside of the cavity for insulation. As a cover to the cavity, use wood, and 1" cuts along top and bottom to let air circulate in and out of the cavity for the heat to circulate from the heat element. that way the covers are flush with the drywall above it.

Is this a bad idea? Or should it work just fine?
I've seen similar solutions where folks do built-in style cabinetry over their baseboard to make it look nice. So, I thought to extend the idea to "hide" them into the wall.

Thanks.
-Chris

STEVEusaPA

Probably bad if you don't get convection under and around the elements, no heat.

STEAM DOCTOR

Definitely bad.

Jamie Hall

Yeah, not so good. It would work, but only if you had ample grille space (the 1 inch slits are nowhere near enough) for natural convection through the elements. The interior of the cavity should be shaped to encourage convection. By Mylar insulation, do you mean the plastic film? Probably need to build out the top of the cavity with solid material -- wood or dry wall -- also shaped to encourage circulation.

You're kind of on your own on this. Even with careful attention to circulation, you might not see more than 50% of the normal capacity.

KC_Jones

If you are going to that much effort, it seems to me wall radiant would get you what you are looking for and probably be easier. Also wouldn't require slits in the walls and question marks on the output.

pecmsg

Read and understand the clearances to combustible material. Standard baseboard ....... No can do!

BillyO

why not just look into wall cabinet recessed convectors? gotta love people who think outside the box tho

EBEBRATT-Ed

@shamu1023

It's all about air flow. When the baseboard gets hot it sets up a chimney effect. Cold air goes in the bottom and is heated, rises up and comes out the top and is replaced by more cold entering air.

Even if you built a properly insulated and heat resistant enclosure you would reduce the heat output. Radiator enclosures will work on HW or Steam radiators if properly designed. I have seen many that carpenters built that would not heat because the openings were too small

GroundUp

You don't necessarily need to use the ugly steel enclosures, if that is the concern. You can certainly design your own wooden enclosures (though mounted on the face as the steel enclosures would be) and have them perform similarly to the OEM enclosures. If a seamless approach is what you're after, I'd also lean toward a radiant wall system over what you're suggesting although I do appreciate the ingenuity! Recessed kickspace heaters is another option as well.

bburd

@OP: Is this hot water or electric baseboard?

Hot water baseboard normally operates at 200°F or less and can be in direct contact with combustible materials. The most trouble you could get into with them is inadequate heat due to restricted airflow.

Electric baseboard operates at higher temperatures and must be installed in strict accordance with the manufacturer’s instructions to avoid a fire hazard. Standard residential units are not designed to be enclosed and may be a fire hazard if installed in an enclosure that has not been tested and approved as safe for the purpose.

Should a fire occur, your insurance adjuster would be looking at the installation.

psb75

Typical baseboard heating units are LARGELY convective heat--i.e. they rely hugely on the free flow of air THROUGH the unit. If that flow is hampered by dust bunnies, dirt on the fins etc. or restrictions of the openings (slightly closed or completely closed shutter), or set-in to recessed cavities... they become very ineffective or "de-rated."
Best suggestion: think about radiant tubing in-wall heat. Especially if you are considering putting in new 2 x 6" studs! Go with 2 x 4" studs with insulation behind tubing.

SuperTech

Would cast iron baseboards be an option for this type of application? I know the cast iron baseboards radiate rather than convect the heat.

hot_rod

I too would go with a radiant wall assembly instead of notching into the wall. Keep all the wall stud space for insulation.

A room load calc would indicate how much wall space would be required.

mattmia2

What about using this style of baseboard and building a recess with adequate clearance top and bottom to mount it flush:

http://www.baseboardrads.com/

Check the heat output, these panel type baseboards will run lower water temps if you get enough of them but might have less capacity than standard fintube at high temps.

I think I have seen other baseboard radiators designed to mount recessed, maybe it was cast iron baseboards of one style or another? Maybe it is from a commercial line?

(This all assumes hot water, electric is likely not an option)

shamu1023

Wow! Thanks for all the great feedback.

To note... I'm not comfortable switching to radiant, as I'm not sur what that entails. I already have the hydro baseboard, the previous owner just looks like he kicked the crap out of them...all smashed fins... so need replacing.

I guess I'm still wondering why this would not work. To be a bit silly, What's the difference if I just did a standard install, then added an extra layer or two of drywall to make the wall flush with the baseboard.

Or is there some reason the hot air get trapped in the cavity?

psb75

The wall "flush" with baseboard IS better than baseboard being recessed INTO the wall. With bb radiators it's pretty much ALL about "convective air flow" and NOT impeding it.

hot_rod

I'm not sure how much output would drop, if any if the air currents did not have a free path bottom to top out of the enclosure. They make recessed boxes that go in the floor, and they get enough convection current moving to work.

Jamie Hall

SuperTech said:

Would cast iron baseboards be an option for this type of application? I know the cast iron baseboards radiate rather than convect the heat.

A good part of the heat from cast iron baseboards -- and radiators, for that matter -- is convection, not radiation. You still need that air flow...

SuperTech

@mattmia2 I think your idea is a great op> @Jamie Hall said:
> (Quote)
> A good part of the heat from cast iron baseboards -- and radiators, for that matter -- is convection, not radiation. You still need that air flow...

I understand the importance of airflow to the cast iron baseboards and radiators, I thought the way the cast iron emitters retain the heat and cool down slower would make them a better choice than fin tube convectors for something like this, given that they have proper clearance for airflow. I assume output will be reduced. I wouldn't try it myself, I'd rather have radiant floors or ceilings. Or maybe just panel rads.

hot_rod

If you use cast iron baseboard there would be no reason to recess it, it does not damage like the sheetmetal fin tube enclosures.

SuperTech

> @hot_rod said:
> If you use cast iron baseboard there would be no reason to recess it, it does not damage like the sheetmetal fin tube enclosures.

I agree. As a kid we put the cast iron baseboards through quite a bit of abuse without doing any damage. Fin tube convectors would not have fared as well.

psb75

It is my understanding that panel radiators deliver 80% radiant and 20% convective heat. Still a huge improvement over fin-tube.

Ironman

Base-Ray cast iron radiators can be partially recessed into the wall and are nearly indestructible.

They are however quite expensive and require assembly on sections larger than six feet.



As mentioned, panel radiators or radiant walls are easier options than what you're contemplating.

Iceman1127

Put a mini split in.

hot_rod

Jindrak said:

There's a company called Concealed Baseboard Heating Co. that makes in-wall heating elements that replace traditional baseboard heaters. Available at Home Depot. They mount in between the studs and are flush on the wall. More efficient as well. 

How are they more efficient? Isn't electric resistance heat near 100%, rgardless of where it is located.

mattmia2

hot_rod said:

Jindrak said:

There's a company called Concealed Baseboard Heating Co. that makes in-wall heating elements that replace traditional baseboard heaters. Available at Home Depot. They mount in between the studs and are flush on the wall. More efficient as well. 

How are they more efficient? Isn't electric resistance heat near 100%, rgardless of where it is located.

If anything it is ultimately less efficient because more heat is going inside and through the wall than if the unit were entirely within the building envelope.