Green Remodel Forum

Our house is still cold even with the heat on. Should we get a new furnace? Or, is there anything else we can do about it?

Do not buy a new furnace before you seal and insulate your home. You can install some insulation in the attic and seal around the windows and doors yourself to save some money. Then hire a home performance contractor to test the leakyness of your house and let them do the remaining part of the work. If you are not crazy about attic or crawl space, just let them test and do all the work. Remember, quality insulation installation is very important. It can not have gaps, voids, or compression in order to be effective. When the house is sealed tight outside pollutants and noise cannot come into the house. After that, most likely you need only a smaller furnace. You save money by buying a smaller furnace and using less energy. You'll feel a lot more comfortable and the house may be quieter and less dusty. How nice that you don't have to clean your house as often. That saves time too! That is priceless!

What does a "home performance contractor" exactly do? How does he test it?

Home Performance Contractors use building science principals to understanding all the systems in your home, especially heating and cooling equipment. What most HVAC contractors won't do is a method of properly sizing HVAC equipment called Manual J. What home performance contractors find most commonly in homes is that furnace and A/C sizing is typically 2 to 3x's over-sized and the ducting system is 30% leaky - meaning 30% of the air you pay for ends up blowing into the crawl-space or attic (wherever the duct-work is located). Oversized systems generally short-cycle - meaning they turn on, use a ton of energy for a short time, then shut off. This is not efficient. Heating and cooling systems actually want to be smaller, and run longer - just like a car has better mileage when driven longer distances on a freeway rather than stop & go through town.

A home performance contractor will consider many things before suggesting a new furnace, or sizing a new furnace. Things like insulation quality & location (i.e. walls, attic, sub-floor etc.), windows & the direction they face (N,E,S,W), building envelope leakage, room size and heating needs (airflow required to properly heat or cool a certain room) etc. etc. If these factors are not considered, your home may never have a chance to be properly heated or cooled, and your energy bills cannot be controlled.

Some of the equip. home performance contractors use to test homes: Blower Door, Duct Blaster, Infrared Camera, Combustion Analyzer, Flow Hood....

If you're looking for a home performance company, let me know.

Thanks. It sounds interesting. It seems my house needs quite a bit of work. I have to think about it.

I agree, there are a lot of things that could be causing the house to be cold. Have you checked your ? If they are clogged, then they won't blow much hot air into your home. It could also be dirty ducts or ducts that aren't insulated or sealed well. It could also be the blower motor or something else.

Our friend, a home performance contractor, said that he sometimes see ducts separated and the attic is being heated instead of the house. Check your ducts to see if the heat is escaping.

A cold and uncomfortable home can also cause by penetration of holes and cracks around the house. Check them during a windy day. You'll be surprised to find all those holes and cracks. Get some Great Stuff and seal them. You can get them from a hardware store.

There is nothing wrong with houses have some holes and cracks. Our house needs to breathe. It can help to bring fresh air into the house.

It is fine if the holes & cracks are just bringing in fresh air. The problem is that they are also bringing in stale air from the attic and the crawl space. I just read this blog and it sounded so gross, http://greenremodelforum.com/GRF/blog/?p=79 . I sure don’t want that attic & crawl space air getting into my house.