Home Improvement Advice? Heating a Cold Basement

[boarder2k7]

I'll second Siress. You can add R5 insulation to the walls for around $1/sqft by gluing a 1" foam board to the wall and gluing a piece of sheetrock over that. It's the option that loses you the least space in the room vs studding it out. Probably less work too. Upgrade to R10 for around $0.50/sqft more.

Whatever you do make sure you drylock the walls first, looks like you're already painted though so not much to change there.

Edit: Also reiterating that the walls matter most. Convective currents flowing up the wall significantly increases the heat transfer coefficient vs convection off of a horizontal surface, i.e. much more heat loss in the walls.

Floor coverings that may work are stall mats. They are durable enough to be a good floor surface. Nearly $2/sqft though and only come in at around R1.

https://www.tractorsupply.com/tsc/product/4-ft-x-6-ft-x-3-4-in-thick-rubber-stall-mat?cm_vc=-10005

All the options here: https://www.tractorsupply.com/tsc/search/rubber%20mat?

[Magmoormaster]

The windows, fortunately, are only a few years old. When we bought the house, it had the hundred-year-old single-pane wood-framed leaded-glass windows. Those are all gone, the only extra sealing I did with the windows was where the OLD outermost wood frame meets the concrete.

Another consideration is the ceiling. If insulating the basement walls would be a bigger project than I care (or have time) to tackle right now, what do y'all think about closing those gaps in the ceiling with the intent of blocking off the cold basement from the heated first floor? We do have a TON of spare ceiling tiles. That won't solve the basement problem but would that maybe help with the cold feed and draftiness of the first floor?

Good, having the windows crossed off the list already is a huge plus.

As for the ceiling, yeah you can do that. In most modern construction (at least in Utah), the floor between the main floor and an unfinished basement will be insulated. That said, just throwing up some ceiling tiles isn't going to cut it. That's probably obvious, but the point is that insulating the floor structure will not be that much easier than insulating the walls. Siress is right, you will get some thermal bridging through the joists, but if you're going to care about that you'll need to reinsulate the whole house. Thermal bridging exists everywhere.

I'll also add that the floor is the least of your concern. Looking at modern construction again, it's very rare that the basement slab will be insulated at all. You will get some heat loss through it, but it's negligible compared to the walls.

Gluing up some rigid insulation is one way to go, but its worth noting that spray insulation in a 2x4 wall has a higher R value.

[Siress]

I don't know about New Jersey but in Massachusetts there is a 'mass save' program that will apply spray insulation for free to cut down on energy usage. There may be limitations to it though such as 'doesn't apply to basements.'

[flyweightnate]

Put an air mattress in the basement and claim living space? Then burn the air mattress before the tax assessor comes back?

[Tarsun2]

or, frame out a small closet and call the basement a bedroom...

[boarder2k7]

And increase your tax rate from basement to bedroom? Buying insulation is cheaper than that...

[Tarsun2]

HAHA good call.

ok, new plan; take the closet out of 2 bedrooms and call it "sectionalized basement"


seriously though, theres no magic to this.
you have to do 2 things:

get heat in the room
and
keep heat in the room

heat goes from hot to cold (one of the few things i remember from physics). so anything that is cold, will pull heat from the air. Adding insulation will slow that process way day. you can do foam board for a quick, easy, and relatively inexpensive solution. or you can frame out the walls and the pink stuff. this will be more work, and more $ but it will really help keep the heat in.
you're not keeping the cold out, but rather keeping the heat in.

as far as the ceiling, having the tiles helps even though the R value is low. remember, heat flow is hot to cold. so you're most likely adding heat to the basement from the floor above rather than losing heat through the basement ceiling. the foam padding on the floor will help with feeling warm.

getting heat into the room is where you have tons of options. electric, gas, active, passive.... id suggest keeping the upstairs heat where it is. you can do the ductless propane heater. they are nice and add some humidity to the room, which helps the area feel warmer... but its $$ to set up/install.
IR heaters are nice, can you branch off your mini split? (i forgot)
electric baseboard? ceramic heater? one of the wall heaters are neat (i have no experience with them).
wood stove? (that turns into a lifestyle though and takes commitment)

if it were me...
foam board and a portable oil radiator

thats my 3 cents

[Diomedes]

It's looking like the best option is insulating the walls with foam board and dropping some foam mats on the floor. That's not something I have the time or money to do this season probably, but the plan would be to have it better for next winter. With that insulation, it likely it won't need an additional heat source. That's the hope. But as people have said, no point in heating without the insulation, so I'll do that first.