We are getting ready to purchase and have installed a new forced hot water baseboard heating system. I read somewhere that one should look for efficiency in the new system as opposed to a bigger system. My question is, what do you look for in an efficient system? We have about 1800 sq ft, three bedrooms one bath upstairs, master br, bath, kitchen, living room, and mudroom downstairs, and off the kitchen a set of stairs taht leads up to a family room, so we're pretty spread out. Also, its an older house so we are insulating and doing new windows to help out. Thank you.