How to Find Air Leaks into House?

[Qs Laptop]

I'm sitting in the basement of my Minneapolis area home watching TV and I can't stay warm without wearing a hoodie, shoes (or slippers) and a blanket. House was built in 1979 so it was after the Carter-era rules on increased insulation were instituted. The basement is a walk-out with a southern exposure. The floor is carpeted but has minimal padding underneath. The north foundation wall is entirely underground. The east wall is about one-half underground, same with the west foundation wall. All windows and patio doors in the house were replaced in 2014 and are energy efficient (very good R-values.)

If I place my face near the electrical outlets on the southern wall I can feel cold air coming into the house. I presume there are many other spots that are leaking air into the house as well. As part of an effort to make the basement warmer I'd like to find and plug any air leaks. I would start in the basement but I would suppose the whole house should be checked.

What is the best way to find these leaks?

I've thought of several ways.

1. Buy an infrared thermometer, one of those laser units where you point the laser beam at a spot and read the temperature. These are $30 to $50 on Amazon. Won't give me the exact location of the leaks but I figure I should be able to track it down to a small general area with one of these devices. Bonus: can use it for other projects or just to play with.

2. Get an infrared thermal imaging camera. These would be perfect for my application but they are expensive, $400 to $500.

3. Light a punk (is used to light fireworks) or a stick of incense and hold it near suspected air leak areas. Watch for movement of the wisps of smoke. This is the least expensive method.

4. Pay a HVAC consultant or gas company tech to come out and map the house with an infrared thermal imaging camera. No idea of the cost, but I presume it would get the job done.

How would you find air leaks? I welcome your suggestions.

 

[NW-Bound]

1. Buy an infrared thermometer, one of those laser units where you point the laser beam at a spot and read the temperature. These are $30 to $50 on Amazon. Won't give me the exact location of the leaks but I figure I should be able to track it down to a small general area with one of these devices. Bonus: can use it for other projects or just to play with...

My infrared thermometer has a fairly localized measurement spot. At a 6-ft distance, the measurement spot is smaller than a cup of coffee of 4-in width.

Yes, I just checked.

 

[Qs Laptop]

I see that Black and Decker makes one that projects a spot of light on the surface being measured and the color of the spot changes if the temperature changes--turns red if it gets hotter, turns blue if it gets colder. Model TLD100. Very useful for detecting air leaks without having to look at the actual temperature numbers on the LCD screen. I wonder how this would work for other applications besides air leak detection.

Otherwise there are a lot of other IR thermometers, point and shoot and read numbers. Some have dual lasers which pinpoint the spot you are measuring and increase the distance you can measure to/from.

What style do you have?

 

[Jerry1]

I talked to an insulation person and was told that the air coming in through windows and things like plugs is due to poor attic insulation. Generally, this makes sense to me. The heated air is escaping through the attic and that creates a suction that pulls the air in. You can plug the areas of infiltration but one of the biggest problems is the attic.

Now, I’m no expert and I always thought different, but after much discussion, it seemed reasonable. I’m planning on getting my attic insulated soon, but the real ticket is to “seal” the attic. It is not cheap but it seems that sealing the attic is the way to get the airflow to stop. I’m not sure yet whether I’m going to go the next step and get my attic sealed but we’ll see.

 

[Qs Laptop]

I talked to an insulation person and was told that the air coming in through windows and things like plugs is due to poor attic insulation. Generally, this makes sense to me. The heated air is escaping through the attic and that creates a suction that pulls the air in. You can plug the areas of infiltration but one of the biggest problems is the attic.

Now, I’m no expert and I always thought different, but after much discussion, it seemed reasonable. I’m planning on getting my attic insulated soon, but the real ticket is to “seal” the attic. It is not cheap but it seems that sealing the attic is the way to get the airflow to stop. I’m not sure yet whether I’m going to go the next step and get my attic sealed but we’ll see.

You're right about stopping all air flow and the attic is a prime area. I've had two contractors out and have gotten estimates on sealing the attic. But I'd like to try plugging any holes I can find in the basement area as well, and this seems like something I could do. Also, we have a 2-story house so I figure the air draw on the basement from attic leaks is not as severe as if I had a single story house.

 

[Qs Laptop]

OK, the Black and Decker has a temperature range of -20F to 320F. So I guess it's not going to be useful for BBQ grilling or cooking, whereas other IR thermometers have a range of -58F to 1050F. Practically speaking, those of you that own these devices, do you do much measuring of objects above 320F?

 

[Scrapr]

Get a blower door test. Along with a infrared camera. Our state it's free (or used to be). I was same as you.But our home was built in the 90's. I had a hoodie on as my wife opened the gas bill. Wowzers. I called a remodeler that did blower door tests & worked with them. They pointed the camera at the can lights above the sink. 1st floor but it was a bump out. Cold air streaming down. Also they checked the ducts. Thet were 50% leakage. The bonus room was hot in summer & cold in winter. Knee walls there. They put in an air barrier & it was 100% better. I'd go with a pro because they have been there done that

https://www.energy.gov/energysaver/blower-door-tests

 

[aja8888]

Under your sinks in the cabinets where the hot and cold water pipes come through the wall is an area where plumbers cut large holes for pipe clearance. Those are big leakers and can be sealed up with expanding foam.

I agree with Scrapr about a blower door test. In Texas those tests were done by the utility company for free. Lots of leaks will show up with that test.

 

[Out-to-Lunch]

In my neck of the woods, you can rent an IR camera at Home Depot for a modest sum.

Also agree with the blower door test.

 

[RetiredAndLovingIt]

Not sure if any of this is helpful to your situation or not but thought I'd mention.
When the gas company weatherized my house for free a couple of years ago, they put foam gaskets inside all the outlet and switch plates.
They weather stripped and adjusted the front door and they replaced the other door from the house to the garage because it had a leaky cat flap. The original door was a standard Home Depot metal insulated door but they said wood was a far better insulator so that's what they used and weatherstripped it as well. Before the work was done both doors had a lot of play in them now they are tight as a drum.
They also ran some kind of duct test which passed but if it hadn't they would have sprayed some kind of sealant through the ducting to fix the leaks. I got a new more efficient gas heater and water heater for free as well (low income program)
They went under the sinks and patched any gaps where pipes went into the wall.
They sealed around the windows on the outside of the house.
They put some kind of gasket around the door to the attic
I also recently replaced my kitchen can recessed lights with sealed LED fixtures and when I pulled the old ones down I could feel the blast of cold air. My house was built in 1992 so not that old but definitely leaky. The new retrofit LED ones are sealed, cheap and easy to install with the adapter that just screws into your light bulb fixture. Once I installed the original 4 and realized how easy it was, I ended up replacing all 18 in the house for less than $200.
I'm in Southern California and it certainly doesn't get anywhere as cold as where you are but I'm also bundled up and under a blanket or wearing a jacket during the day. I keep the house at 70 to save on energy costs. In summer at 68 degrees it's pleasant in the house, in winter at 70 it's freezing. I have a 2 story house with cathedral ceilings so the heat all goes up, nothing I can do about it.
Also check with your local gas and electric company for energy saving programs or rebates.

 

[Sunset]

I'm sitting in the basement of my Minneapolis area home watching TV and I can't stay warm without wearing a hoodie, shoes (or slippers) and a blanket. ...
....

The basement is always colder than the rest of the house because cold air is heavy and falls down to the basement , while the warm air goes up.

Your furnace is probably burning the air in your house , which creates a negative air pressure, so the house sucks in air by any opening it can.

If you seal up everything super tight, you can end up having problems with the furnace as it starves for air to burn. How will you supply air to burn to the furnace ?

I call BS on the insulation man saying the attic letting heat out due to poor insulation is causing air to come into the house. Seal the attic trap door and insulate it and make sure the attic is insulated to R40 at least.

For the basement it will be hard to make it warm unless you turn up the entire house heat. Perhaps a separate heater for down then for when you are there is the answer.

 

[JoeWras]

I call BS on the insulation man saying the attic letting heat out due to poor insulation is causing air to come into the house. Seal the attic trap door and insulate it and make sure the attic is insulated to R40 at least.

For the basement it will be hard to make it warm unless you turn up the entire house heat. Perhaps a separate heater for down then for when you are there is the answer.

Well there is a "stack effect" if you are leaking a lot of air out to the attic. But yeah, he could be BSing too. Before just piling insulation up there, I agree that the attic trap door can be a huge problem for the stack draw. Also, all the electric and pipe penetrations through the top plates in the walls are likely open and should be sealed with expanding foam. To fix this right on a retrofit, it is theoretically simple, but messy and thankless. Shimmying on your stomach between trusses or joists, not falling through the ceiling, wearing a P100 mask and Tyvek suit, etc. is required to do it right.

Northern basements in winter are always a problem and aux heat requirement is typical.

 

[JoeWras]

I didn't "solve" my leak issues, but I reduced them by going for the heavy hitters. It helped a lot on my 1980 house which has similar issues.

You can just find the problems on a 1979 house because there are weak points they didn't address typically back then, despite the start of improved standards. Fix these first before doing any testing of any type from a blower door, to a smoke-punk, to fancy cameras.

The US government actually has some very good write-ups on this. Check them out.

General info on insulation: https://www.energy.gov/energysaver/adding-insulation-existing-home

Do it yourself easy projects: https://www.energy.gov/energysaver/do-it-yourself-energy-savings-projects One of the projects here is an attic stair box.

BTW: I work on Habitat for Humanity homes and the steps we take to air seal a house are amazing. I won't go into every detail, but suffice it to say, none of these can be done in retrofit. Habitat homes in our region score extremely high on the blower door test.

 

[target2019]

If you seal around a basement outlet, the cold air goes elsewhere in the basement. Are the framed walls insulated? I know mine aren't.

 

[Zathras]

I am in Minnesota and got a free energy overview.
This worked very well as they identified trouble spots and gave me methods to mitigate them.
Very knowledgeable folks, I highly recommend it.

Here is the site for Xcel energy’s “Home Energy Squad”, https://www.mncee.org/home-energy-squad

If you have a different utility provider check their site.

 

[mystang52]

This might help, some, for your electrical outlets:
https://www.lowes.com/pd/Sigma-Electric-6-Pack-Weatherproof-Electrical-Outlet-Gasket/3343874

 

[HawkeyeNFO]

What does your gas or electric company offer for free?

A couple of weeks ago, a big snowstorm knocked our power out for about 36 hours and the outside temp was in the teens at night, 20s in the day. During the first day, one of our neighbors complained that their home had cooled off into 40s, while our house built in 2019 stayed in the 60s until the second day, when the temp finally dipped into the 50s. The new methods of insulating homes are clearly much more effective.

 

[ERD50]

1 and 2 from your OP. Cheap and easy.

It was sort of mentioned, but the furnace drawing in air pulls cold air into the house. I've considered (with the non-sealed type furnaces), to bring in a small duct from outside to the furnace room (could be PVC, just like the sealed-combustion HE units). Add a power vent, or small blower/flap that comes on with the furnace fan. That would draw outside air directly to the furnace and mostly up/out the chimney, and not draw cold air through the house.

-ERD50

 

[Qs Laptop]

Thanks everyone for your response. Some good ideas here.

Regarding the blower door test, yes, we had that done back in the fall of 2012 or 2013. They identified the major air leaks as the first floor patio door (going out to deck), the attic access door on the 2nd floor, and various windows. Warned us about any holes cut into the 2nd story ceilings like electrical boxes for light fixtures, or the chimneys for the water heater and furnace. Also mentioned the basement patio door and a couple outlets. A couple of days later I put weather stripping around the perimeter of the attic door and positioned a piece of fiberglass insulation in the attic on top the access door before reinstalling it. All windows and patio doors were original from 1979. We replaced all of them in 2014.

The furnace is a 20 year old Carrier 94% efficient unit with it's own air intake pipe. The water heater is an energy efficient power vent design that has it's own air intake. When the water heater was replaced the chimney was completely removed. The contractor went into the attic and put a plate over the hole and I climbed up there and sealed around it with spray foam. I think I sprayed around the hole of the old furnace flue as well.

The basement is insulated, but it's not fiberglass batting, it's rigid foam insulation (the rest of the house is fiberglass insulation.) I have removed an outlet cover and can see the builders did a lousy job framing the insulation around the outlet box. Hence the air leaks.

My home office is in the basement and, yes, I do have an electrical space heater. It's on right now.

I think I'm going to contact my gas company and see what kind of programs they have for energy and insulation audits. It's 10 below zero outside right now--I can't imagine doing a blower door test when it's this cold.

Anyway, I think I'm going to fix the easy air leaks--the basement outlets, the circuit breaker box on the basement wall, and anything else I can find with an IR thermometer.

Speaking of IR thermometers does anyone else have any comments on them? Anybody else besides NW-Bound have one? I like the Black and Decker feature whereby you get a visual cue if there is a temperature differential detected as you move the device. Will the temperature range of the Black and Decker (-20F to 320F) be adequate for using the thermometer for other things besides detecting air leaks?

 

[Bamaman]

I've lived in one home built on a concrete slab. Then we had two homes with fully finished basements. Our current (and last) home has a conventional foundation with a 42" crawl space with the HVAC under the floors.

Despite what any thermometer says, slab houses and basements seem to radiate outside temperatures. And in winter, they just feel cold. Our house with the crawl space feels warmer and more ocmfortable.

The homes we have had with natural gas heating seem warmer. The homes with forced air heat pumps will feel colder in the winter. Heat pumps do well in summer heat, however.

We presently have two heat pumps. When temperatures drop, I shut off the upstairs heat pump since only one bedroom up there is being used. I do get some heat from below, but I blow it downstairs with a big ceiling fan. I run a small space heater in the upstairs bedroom, and it's toasty.

 

[Mykle57]

Lots of great advice here. I also build houses for Habitat in MA and agree with the above post about the extraordinary work done to insulate their homes.

Since you're taking specifically about basements I'll add one more thought; the sill plate on older homes are a big leaker. Those boards that lay on top of the foundation. As they age and dry out gaps let wind blow right in. Caulking and foam can help there although it'll be tough to get access in a finished basement.

Sent from my SM-G998U1 using Early Retirement Forum mobile app

 

[ERD50]

...

Speaking of IR thermometers does anyone else have any comments on them? Anybody else besides NW-Bound have one? I like the Black and Decker feature whereby you get a visual cue if there is a temperature differential detected as you move the device. Will the temperature range of the Black and Decker (-20F to 320F) be adequate for using the thermometer for other things besides detecting air leaks?

Yes, I have the 'regular' one. I find all sorts of uses for it (but I'm a hobbyist/DIY and generally curious type), including tracking down cold spots in the house.

-ERD50

 

[Jeffman52]

Be careful not to stop up the attic air flow from outside to into the attic. You need that during the hot months or the hot air has no where to go. That will cause humidity and even warping of your decking due to excessive heat.

 

[NgineER]

Started on a reply but did not finish. Lots of good suggestions in here. Ensuring the attics are properly sealed would be good. Maybe even caulk the attic hatch.

I'm also in MN and a house from the 70's, but a century older than yours. You clearly have exfiltration if you have cold air rushing in around outlets. Even if your house has wall insulation, I doubt you have a very good air seal, i.e. vapor barrier and an exterior air barrier. They probably considered the kraft paper of the insulation a vapor barrier, and unless you tape all those seams, they won't perform great...

I have used the outlet gaskets, and they help a little.

In my house (balloon framed) I sealed all penetrations into the attic, air sealed the exterior foundation-sill joist with a self-adhered air barrier and added a foot of insulation in the attic. I never did a follow up air leakage test, but the initial test had a combined infiltration equivalent to a nine square foot hole in the wall open year round. With 10 degrees below this morning it is not very pleasant. We reduced our gas bill by at least 40% doing the fixes, which paid off in the first three months after doing the mitigation.

The IR gun is cool, but somewhat pointless. It will tell you that it is cold where the air is leaking in (Which will be by an outlet or wall penetration, but it won't necessarily tell you where the cold air is seeping into your house from the exterior.

 

[Out-to-Lunch]

Speaking of IR thermometers does anyone else have any comments on them?

I guess I will repeat my thought to rent an IR camera from your big-box store. IME, having a 2D picture of the area in question is very instructive.