Insulating a balcony floor
AaronRosenthal
| Posted in Energy, Heating & Insulation on
Prospective client has a 7th story townhome (3 levels) made of concrete.
Before they bought, the old HO removed the patio doors and made it into an extension of the living room – 13 sq yd.
Double paned glass on the entire outcropping, but man, even through the dense mat and rug over laminate and underlay, that patio floor is COLD. They want to use it as a baby’s bed/play room until they sell and move in the spring. They want wall-to-wall in the area.
Option 1. Under floor heating, 1/2″ ply and carpet glues on.
Option 2. Baseboard heaters, rip everything out to the concrete, 5/8″ XPS, 1/2″ ply and carpet.
I’d like the benefit of your advice.
Quality repairs for your home.
AaronR Construction
Vancouver, Canada
Replies
Optio #2
Option #1 would be a money sink. That concrete would drink any underfloor heat like water (almost). That chunk of concrete sticking out has four sides exposed that you can't insulate. Basically a big wick like heat sink.
Keep as much heat in the space as possible by insulating between the heat source and the the uncontrolable heat sink.
Thanks DaveQuality repairs for your home.
AaronR ConstructionVancouver, Canada
Nothing scientic here.
I built two buildings on similar construction about 30' apart. Both have block foundation walls with concrete slab floor. On the second building I insulated the inside perimeter of the block foundation and under the slab with 2" rigid foam.
Durring the coldest part of last winter I spot checked slab temperature with a hand held IR sensor. The insulate wall/slab building slab stayed warmer by about 5 degrees over the other.
We keep both building at an unoccupied temp. of 50 degrees and occupied temps of about 65. that 5 degree slab temp difference represents roughly 30% + of the load.
Option #1 - you do mean radiant floor heating? I'm assuming that means minimal raising of the floor ... but you would raise it, so how do you handle the floor change from that room to the next? Assuming you don't/can't insulate under it, it's a bad idea like the other poster said.
Option #2 - you mean 5/8" insulation and attach the plywood through it into the concrete?
Generally it sound like the previous owner kind of did a strange thing for a condo situation. Surprised the CC&Rs didn't restrict that change. Regardless of underfloor heating or over floor, from an energy standpoint, the change is a bad idea ... 'cause it does tend to suck energy out very readily.
edit ... I'm a little surprised they allowed an owner to do such a thing ... substantial alteration of the exterior/appearance of the condo. Most CC&Rs are set up to prevent that so the complex doesn't start looking like a slum w/ everyone wanting to make different changes.
Edited 11/13/2009 8:59 am ET by Clewless1