How to keep Basement Warm

[nhoj]

My home was built in 1973 and I have trouble keeping my Basement warm in the Winter Time. Is there any way that one can improve the heating in the Basement? I have 3 heat registers in a 33' X 26" basement.

I have a RUUD Furnace 94% effect-net.

My basement walls are block. Not finished, although I am going to have them finished. I had to tear off the wood paneling to find vis queen and stir o-foam under it which was causing mold. Who ever do it had no ideal what they was doing.

I did put R 25 insulation up in where the basement and house meet floor rejoices are . Hopefully that will cut down on air coming in.

[juster]

If your furnace vents are at the ceiling level and you have open walls you can extend the supply duct to the floor level. This would be the best time to do this, with the walls open. You do have a large basement so you may also want to add electric heaters for supplemental heat for when it gets really cold. Again with the walls open easier to do.
Depending on what you are using your basement for, say if you are going to finish the basement, you may want to insulate the floor by installing a raised floor with insulation under it. It should be dry if you are thinking of doing this.

[Freon]

You need to be careful. By increasing the heat to the basement you will be taking it from other parts of the house. If you feel your house is very warm now, then this shouldn't be a problem. Just remember you're robbing Peter to pay Paul since your furnace can only produce the same heat no matter how it's distributed.

The first thing is to check airflow. Do you feel a good flow coming from all the basement vents? If not, you'll need to increase the diameter of the main supply duct feeding those registers. I will assume the registers are for 6" ducting. So you'll need a 10" to 12" supply duct feeding them, depending on how many bends between furnace and registers.

Also check if there is a return register in the basement. The air from the supply registers needs to get back to the furnace and that's the function of a return. If there are no returns in the basement you need to devise a path for the basement air to get to the closest return. If doors are involved you may be able to cut 1" to 2" off the bottom of the door to allow air to return.