Cold air leaks means heat loss elsewhere?

[wahoowad]

I have a few known air leaks, most rather small, around a couple doors. They really are minor and I figured it was beter than too tight a house. Recently I noticed a sizable leak of cold air escaping past my prefab fireplace. I feel this comes from cold air collapsing down my chimney chase. My question is about the air volume balance that mustbe going on in my house. I assume the volume of cold air leaking in means I have other air escaping (else my house would be airtight and no inbound leakage). it probably is warmer somehow leaking out upstairs although I don't know of any specific locations.

The only places I can think of are my two bathroom fans - but wouldn't they have baffles that open/close when the fan is turned on? Or are these fans simply large sources of air escaping my house?

 

[begreen]

The stove could be pulling combustion air from the outside (chimney). Or does the stove already have an outside air connection? If not, can it be added?

Small leaks around doors add up. A 1/8" crack around a 36" door can equal about a 30 sq. in. hole.

Bath fans often do have flappers to stop heat loss, but they are usually crude and sometimes stick open.

What is the age of the house? Is it quite air-tight already? If so, an air to air heat exchanger may help to be a controlled source of fresh air while reducing energy loss.

 

[Sandor]

My favorite method for looking for heat loss is to observe the roof in the morning, after a frost.

On my new home, I noticed the frost was melting around the vents from the bathroom fans. I removed the hoses to the roof vents and ran them to the soffits, to kinda create a heat trap.

If the cold air is rushing in, the heat is certainly escaping somewhere.

The best politically incorrect way to look for air leaks is to walk around a still home with a lit cigarette. Hold the smoke around attic access points, bathroom fans, windows, registers, ceiling light fixtures, etc. The smoke will go with flow. This is also a good way to see the way cold and warm air is migrating throughout the home.

I was doing some trim work on a new home with a prefab fireplace that was recently installed. Talk about cold air infiltration! The chase was never insulated.... so the whole insert was very cold, with more cold air entering through the fresh air intake.

 

[roac]

The best way to figure out where and how much heat is escaping from your house is to have a heat loss analysis done. These use to be performed or hired by the utility companies. They basically walk around your house with heat sensing equipment. Same stuff the armed forces uses in all of their heat sensing applications just a lot less sensitive probably. Pretty easy to tell where you need to make changes.

 

[joshuaviktor]

First off, an incense stick works like a cigarette. 2nd JCP&L doesn't do those energy analysis. See if you can get a friend in the fire company to borrow a thermal imager. They use them to find people in burning houses. Should work just fine on heat loss. BTW, someone good enough with them can see the studs in the walls.

Joshua

 

[roac]

First off, an incense stick works like a cigarette. 2nd JCP&L doesn't do those energy analysis. See if you can get a friend in the fire company to borrow a thermal imager. They use them to find people in burning houses. Should work just fine on heat loss. BTW, someone good enough with them can see the studs in the walls.

Joshua

LOL Yeah just hope they don't need it when your friend is helping you. That is an expensive piece of equipment to allow out. Just bite the bullet and get it done professionaly. Hate to see someone die just so that I could save a few bucks...

 

[elkimmeg]

Word of advice concerning bath vents yes all modern ones have a back draft preventor bafflet. Once the are routed ontside the insulation envelope, they are required to be insluated. Their purpose is to get the most amount of moisture exiting your home. Non insulated flexible plastic vents, condensate in the cold air and prevents moisture from exiting. In the neighboring town one collected so much water it backed up into the fan unit, created a short curcuit and resulted in a fire. For these vents to work properly, they must be pulled tight no dips and wandering a straight path is needed. The problem with just dumping them in the sofit is it rots out the trim and rafter ends. They should be terminated to a proper termination recepiticle. The insulation also creates a margine against colder air infiltratiog the home, This kind of detail is often overlooked.

 

[joshuaviktor]

Who does the energy survey professionally? I thought only energy companies do them.

 

[roac]

Not sure. I don't think they ever did them, they sub'ed out the job. If you call the local utility they might know. After the utilities stopped paying, most of them probably went under. Maybe online yellow pages? I'll look at mine and see...

 

[roac]

Ok checked mine but obviously everyone is home watching football. They should be listed under this maybe "Energy Conservation Products & Services". That is what came up when I typed "energy" at dexonline. YMMV

 

[G-rott]

Check local insulation contractors. Provesionals will offer blower door test, and/or IR scans. Many will deduct some or all of the cost form any work they preform as a result of the survey.

Garett