Last fall, we had our basement finished by a small, local general contractor who came recommended by a friend. The job added about 700 sq ft of finished space to our previously 2000 sq ft home, which is heated by an electric heat pump, and has no separate heating zones.

The contractor added 4 additional registers to heat the basement, but the result was terrible. All throughout the winter the basement remained uncomfortably cold. So much so, that our children were unable to play there. The themostat is on the first floor, and when we turned up the heat, it became uncomfortably hot (!) on the upper two floors of the house, and still made the basement only just bearable.

To experiment, I spent a month closing the registers on the upper two floors (to keep them cooler and force more of the heat into the basement) -- this worked a bit, but still did not create a comfortable balance between the basement and the rest of the house -- and our electric bill absolutely sky-rocketed when I attempted this solution! (Was this an unwise way to attempt to fix the problem?)

I talked to the contractor about it this week, and he was quite friendly, but I feel as if he avoided addressing the issue directly or taking responsibility for the problem. Before I speak to him again, I'm hoping to be a bit more informed.

My question is this: Do you have guesses about what the problem might be -- or where someone would start investigating? What might be going wrong? If I push a bit, I want to be confident that he's considering the right things, and not avoiding issues that might have been poor decisions on his part.

(Our house is only 4 years old and therefore has windows and doors that are energy efficient. The basement is exposed on the back wall and has two large bays of windows and a set of french doors. The contractor used R-19 insulation on the exposed wall and I believe no insulation on the three poured walls. If I understand him correctly, he claims that poured concrete walls are very thick, and also have a layer of insulation buried on the outside, and therefore do not require interior insulation.)

Thank you so much for any ideas you can generate!
Your time is much appreciated!

Is this forced air registers?
If so are the registers in the ceiling or walls?
If so is there any coldair returns?

Trying to help let us know.

Is this forced air registers?
If so are the registers in the ceiling or walls?
If so is there any coldair returns?

Trying to help let us know.


Yes, they are forced air registers.

The registers are on the walls, about a foot up off the floor.

To be honest I'm not sure about the cold air returns. There is only one vent that might be a cold air return. I'll look into it. If it is a cold air return, there is just that one.

Thanks for your further questions! Let me know what you think.

The way to check for cold air returns would be a sheet of paper over the register grill.When the blower is on and heat is blowing go the grills and check with a sheet of paper.

If it's a return that paper will be sucked up to the grill and if it's a supply hot air it will be blown away from the grill.

Normal setup is a proper sized supply and proper sized return. This has to be balanced or the system will not move the air as needed and you will have problems heating that area.

Is the duct work above a drop ceiling?
Have you changed the air filter at the blower area?

So many questions can be asked to help you understand how this should be.

What size are the runs to the wall grills in the basement?

Did the contractor install dampers in the ducts to the 4 runs to the walls?

Maybe Mygirlsdad and or others will see this and help with there expertise on this.

It is just a basement, it will not be the same temp as the upstairs. Concrete stays cold 56 degrees. Did they put in square registars or round?

Thanks for all the questions and input. I'll try to answer some, and I appreciate any and all ideas. I know that a full diagnosis can't be made online, I'm just looking to generate a list of possible problems, so that I know what types of issues might be responsible.

The ducts are above a drywall ceiling and then come down the walls. The registers are rectangular. The filter in the furnace was recently replaced.

Could these things be sources of possible problems?

So if I understand correctly, the one possible problem that's been generated so far is a lack (or inadequate number of) cold air returns. Is there a way to assess this, or would we just need to go to the expense of adding cold air returns to find out if it helps?

Joshdta, I anticipated that the basement would never get quite as warm as the upper floors, especially given that the thermostat is upstairs. However, shouldn't it be possible to heat the basement to at least a useable temperature?

Thanks for any other suggestions about what might be causing the problem!

Do you have carpet down there now??

Also you can let the fan run on the on mode and this will help to even the temp out between the 2 floors

Just a quick answer but sounds like there is no proper heating there
If it's a basement it will need a lot
Turning up the stat on the higher floors will just make them warmer as heat rises
I suggest you think about the wall structures around the basement and add radiators or some form of under floor heating
Radiators are good
Underfloor heating might be more expensive
Get a plumber in - electric heating wong cut it as it is colder down there

Yes, wall to wall carpet in most of the 700 sq ft, with linoleum in the laundry room and bathroom.


also you can let the fan run on the on mode and this will help to even the temp out between the 2 floors

I'm not sure what this means.. :rolleyes:

On the t-stat you have a auto and a fan on mode, by letting the fan run will help circulate the air

To heat a basement you need twice the amout of heat runs as you have upstairs, then it the summer you will have to close them all down to keep the ac from freezing out the basement. Do you have the block walls painted? Or drywall on all the sides? How much insulation was it the walls?

to heat a basement you need twice the amout of heat runs as you have upstairs, then it the summer you will have to close them all down to keep the ac from freezing out the basement. Do you have the block walls painted? or drywall on all the sides? how much insulation was it the walls?

All of the walls in the basement, poured concrete and block, are now drywalled. The block wall has R-19 insulation.

I was concerned from the beginning that the contractor simply skimped and put too few registers down there in order to save money. Essentially, there are four new registers in the basement, but upstairs, the comparable area is heated with eight.

Would you guess that this is really the major problem? Would adding more registers take care of the problem? (Thanks again so much for your time, Joshdta!)

Yes, is your furnace close to the carpted area? How many supllys do you have in that room?

Chances are the heat system was designed and sized for the 2000 sq. ft home.adding another 700 sq. ft to it ,could mean the heat system is now to small to do the job,,

yes, is your furnace close to the carpted area? How many supllys do you have in that room?

Furnace is now in a small closet, which does not have carpet, but the room around it (bedroom) does.

There is just one register in that bedroom.

chances are the heat system was designed and sized for the 2000 sq. ft home.adding another 700 sq. ft to it ,could mean the heat system is now to small to do the job,,,,

I was also afraid that this could be the problem. :eek:

I'll feel so disappointed if this is what it comes down to, because I feel as if the contractor should probably have considered this and included it in our discussion, but also because we won't be able to afford to put in an entirely new system for quite some time. So our dream basement won't be usable for the three-four months a year when we need it the most. :(

How many btu's is the furnace you have now?

There MAY be a way out of your problem: High velocity HVAC

Ten Steps To Installing A High-Velocity HVAC System - How To - Air Conditioning, Heating & Refrigeration NEWS (http://www.achrnews.com/Articles/How_To/09045cd623f5a010VgnVCM100000f932a8c0____)

It uses small tubes about 1.5" in diameter. I have been in structure that had one, a residence on top of a barn.

How is it going?

This thread was first posted 8 months ago,, I hope the problem was solved