Hello evryone. I'm in the early planning stages of finishing my basement. My furnace and hot water tank are under my stairs in the middle of my basement. Not the best place. My question is how do I make my furnace and hot water tank accessible without placing a door in front of each unit? My furnace faces the south side of the basement while the hot water tank on the east side. Thanks. Peter.

If you enclose the appliances and you use gas to heat with you better make sure that whatever you do includes making sure that there is enough combustion air getting to the appliances/furnace/water heater.

I agree, don't close in your furnace, it needs air. Make sure air is available with vents.
Be careful without enough oxygen supply your furnace could emit carbon dioxide fumes. And that means one day you don't wake up!

Hello. My furnace is a high efficiency. Doesn't this mean that it's OK to box in??

NO. You have to follow the manufactures installation instructions. You also have to provide clerance for servicing the furnace and water heater as required by code or the manufactures paper work. Your water heater will need combustion air also. If you do not follow the code/instructions and you have a fire your insurance will not pay off. Been there and seen that.

The company installing the heating equip. should have the specs, how big is the closet? And is the furnace a 2 pipe system?

Your furnace must have an adequate supply of combustion air. Many high efficiency furnaces have a duct to the outside for combustion air, the 2 pipe system, usually white PVC. If so, box it in as tightly as you want to and long as you leave room for servicing it. Otherwise, you need to find the specs somewhere on combustion air. My 80% furnace needs 40 sq. in. free area. A typical louvered door should easily meet that. Same thing for the water heater.

Oh, by the way, although carbon dioxide can lead to suffocation, it is carbon monoxide that is the big killer.

labman you are correct my mistake, Both however are dangerous and proper venting is required