Home Matters
Shading and Windbreaks
Shading and windbreaks can play a large role in the energy efficiency of both your heating and cooling systems. Shading the exterior of your home in the hot summer months can help keep heat from building up on the interior and wind breaks can be beneficial in the winter months to help block harsh north and north west winds that pound on your home. This is important because the wind affects the amount of heat loss, comfort and durability of your home.
Shading typically comes from large trees located near your home but other buildings can also provide shading. The main thing we are trying to accomplish is to limit the amount of solar heat gain in the summer months. Most of this heat gain will be coming in through the windows. As the sun moves across the sky we will get morning light in the east windows, mid day light in the south windows and late afternoon light in the west windows. The morning light we get in the east windows is considered desirable by many people but it still is a heat gain on the house. West windows are nice for watching the sun set but think about when we have the hottest parts of the day, they are usually in the late afternoon. West windows can really produce a lot of heat. Trees or the overhangs on the house can easily shade south windows. The sun is high in the sky on those midsummer days so a decent overhang above the south windows will do a lot of shading. We can’t accomplish much shading with overhangs on the east or west because the sun is either rising or setting and is low in the sky.
Windbreaks work best when they are located some distance from the house so they deflect the wind up and over the roof. They can also be affective in controlling snowdrifts. It’s important that windbreaks are at least 15 feet from the house; closer and you actually trap heat that increases summer cooling costs. Many farmsteads have trees (usually pine trees) planted around the northwest corner of the property. This is a classic example of a windbreak. In urban areas, windbreaks can come in the form of buildings, landscaping and fences usually provided by the neighbors.
Check out the Arbor Day Foundation web site for detailed information on how to plant trees for shading and windbreaks. www.arborday.org Do two separate searches one for ‘windbreak’ and one for ’summer shading’. Remember we are in hardiness zone 5 when you select trees.
Assess:
Take a walk around your house and see what you already have that might be beneficial for shading and wind breaks. On a sunny midsummer day take note of the sun that enters your house in the morning, mid day and evening. On a windy day, go outside and observe how strong the wind blows around your house.
Goal:
Long term
The long-term goals would be to create a future windbreak and some future landscaping that would eventually provide summer shade. Any landscape plans should include consideration of how it will affect the sun and wind exposure on the house many years later.
Short term
If you have plenty of space on your property, some reshaping of the grade could be done that may deflect wind. Some fencing in the right place could also help.
To help with heat gain, you may add awnings over the windows on the south face of your house. On average a 30” shade over the window will do a great job of shading in the summer yet let sun light in during the winter months. On the east and west side you can use your interior drapes and blinds to cut down on the amount of heat gain.
One thing we don’t think about much these days is the idea of exterior shutters. Many homes have ‘fake’ shutters for looks but there was a time they served a purpose. Shutters on east and west windows control the heat gain at the exterior before anything enters the house. Shutters can also be used to add a layer of insulation to the window, protect the windows from storm damage and add a layer of security. Wouldn’t that be fun to have something so low tech yet so effective on you home?
Exterior Water Management
Assess:
Homes in Iowa built before 1940 share some similarities in their construction. Basements were shallow and at least a couple of feet of the foundation was above grade. This required less excavation. Basements were also not considered living space as they are today. They were used to store fuel for the furnace and canned goods. Often the clothes washing area was in the basement and maybe a workbench with some tools. There was typically no need to worry about a little water that seeped into the basement because there was nothing it could harm. A bigger concern was the septic system backing up. Houses tended to sit on the high ground so drainage wasn’t an issue.
Now let’s take a look at what you have:
Start in the basement and take note of any areas that are damp or look as though they have been damp in the past. Be sure to pay careful attention to the location(s) in the basement where you are seeing signs of moisture. Look for a sump pit with a pump in it; it’s not likely you’ll find one. If you do find one, make sure it has a lid and it is sealed for radon and soil gasses.
Now let’s go outside and have a look around. Walk around your home and take note of the height of the dirt next to the house and to about 10 feet away. Take note of which direction the ground slopes – toward the house or away from the house, and about how much difference there is in height. As you’re walking around, also note where the downspouts from the gutters dump out and which way the water would likely run. Another thing to check for are high volumes of water coming off the roof at the valleys.
Next we’ll walk around the property looking at the grade beyond the house. Are there areas where water will pool after a rain? Does the neighbors’ house sit higher or lower than yours and does any of their property slope toward your yard? And where does the water go when it leaves your property? The last thing to take note of is your hard surfaces, such as the driveway or a patio. Note how much of your property is covered with hard surfaces and where the water drains. You may also have a cistern (an underground water storage tank) that’s not in use or has been filled in; make a special note here, we could have some fun with this. Draw a map of your property showing the directions the water flows around your home.
sump pump pit with cover
roof valley
Goal:
Our goals here are fairly simple, we want to have good drainage around the house so the basement stays dry, and we want to keep as much of the rain water on the property as we can (I know this sounds crazy but be patient, we’ll explain).
splash flashing
splash block
Solutions:
We’re going to deal with the drainage in two steps. First we’ll work with the area around the house and next we’ll work with the rest of the yard.
- The grade around your house should slope away from the foundation at least six inches in the first ten feet. It’s very important that water coming off the roof and from around the house not pool next to the foundation. This may not be easy to do if the landscaping is thick and mature. Do the best you can. If you’re having water problems in the basement adjacent to a low area in the grade, the landscaping will have to be removed so the grade can be corrected. It’s not just the dirt areas we’re concerned with, you also need to consider any concrete walks or patios that run along the house. They may have to be raised or replaced to keep water moving in the right direction.
- Now the gutters – who loves gutters? Not us, we think they’re a pain in the kiester. Generally they are an evil necessity unless you have very deep overhangs on your house, (three feet or more) and you could possibly remove the gutters. The gutters have to be clean to work; there is no way around this. Gutter toppers seem to do well in light rain but when you really need the gutter to perform (in a heavy rain) you better have as much open space to catch water as possible. It’s best to try to eliminate the source of plugged gutters, which is leaves, sticks, walnuts, etc. Prune the tree limbs that hang over the house to help reduce the leaves that fall on the roof. If you must use a topper, try the removable, open screen type that lets as much water in the gutter as possible yet can be flipped up to allow for cleaning. If you have a large roof, you may want oversized gutters, or if there are water problems in the basement, such as in the corners where a roof valley dumps a lot of water, you may need to put a splash flashing on the gutter to help keep the water from overflowing.
- Next the downspouts: The best situation is an oversized downspout that dumps on a splash block that guides the water away from the foundation by at least four feet or more. An oversized down spout will pass debris better and using a splash block instead of more down spouting as a leader is easier to take care of. Leaders (extensions) tend to get smashed or disconnected and then the whole system is compromised.
- Now let’s talk about something fun – a water collection cistern. Many of the houses in this era had cisterns that collected roof water via the gutters and downspouts when they were built, especially rural properties. Once in a while they are still working but most have been either destroyed or filled in. If you have a cistern that’s been filled in, consider restoring it by installing a liner to prevent water loss through leakage into the ground. This water is not to be used for drinking. Collected rainwater can easily be used for watering gardens and landscape plants. The old cisterns had a hand pump mounted above them and you can still find these at auctions and in Grandma’s barn. If you don’t want to pump the water by hand you can use an electric pump to do the same thing. If you don’t have a cistern but would still like to collect rainwater, use a rain barrel, or make your own cistern. You will be surprised at the amount of water you can potentially collect. For a simple calculation take the square footage of your home and multiply by 32 (rough average of yearly precipitation in inches) divide by 12 (gives you cubic feet of water) and multiply by 7 (number of gallons in a cubic foot). Example – 1000 square foot house x 32inches divided by 12 equals 2667 cubic feet of water times 7 gallons per cubic foot equals over 18,000 gallons. WOW! If you live in town, be sure to check with your water utility for any restrictions on the amount of water you can collect; there may be rules you need to follow. www.rainwatercollection.com
Now, for the rest of the yard. Our main objective is to keep as much of the rainwater as we can on the property. In town, most of the time runoff heads toward the street to the storm sewer and dumps in the local river or stream. In rural areas, the water heads to the ditch and eventually to the river as well. Along the way it picks up yard chemicals, pet waste, gas and oil from the road, and other garbage along the way. This is not helpful to Iowa’s rivers and streams. Besides, don’t we want to keep as much water on our property as we can to nourish our plants?
- The first thing we want to do is reduce the amount of impervious surface (typically concrete) we have on our property. In homes of this era it’s not uncommon to have a gravel driveway or possibly two narrow strips of concrete to drive the car on. This is good, resist the temptation to pave the whole thing if you can. If you feel the need to have some hard surfaces around your home consider pervious concrete or brick pavers when it’s time to replace the concrete. Both will let water soak through with less runoff. Caution – pervious paving may allow water to drain toward the foundation.
- Second, look for a good place to install a water garden. This may be that low spot you saw when you were assessing the land, or pick a place where there is a high concentration of water moving across the ground during a period of rain. These could be good spots to collect a significant amount of water. If you are not collecting roof water in a cistern you may want to divert the downspouts via a tile to the water garden. One note of caution though – do not locate your water garden where it will cause trouble with your foundation. It should be located at least 50 feet away from the house. www.rainscapingiowa.org
A good resource is EEBA’s (Energy & Environmental Building Association) Water Management Guide. www.eeba.org
Questionnaire
Now that you’ve finished this section, take some time to fill out this questionnaire to assess your home’s exterior water management. Keep it with the other questionnaires to build a resource you can reference when tackling projects at home.
Windows
Assess:
(Let’s find out what you have)
One of the most common windows in Iowa will be a single pane, (one layer of glass) double hung, made of wood. Double hung windows are windows with two sashes, one above the other. Many times each sash will be divided into a number of smaller panes of glass. The dividing bars are called muntin (yes that is spelled correctly) bars.
Some windows may be fixed (non-operable) and do not open. You may also have windows in your basement that hinge at the top and swing up to a hook to hold them open (awning windows).
At one time, most of these types of windows would have had a storm window and a screen that could be switched out in the winter and summer. Each of these would have been in a separate frame that hung on clips from the outside at the top of the window, and held in place with a hook from the inside at the bottom. If you are lucky you still have these storm windows and screens in your basement. If not there may still be signs that you did at one time. Look for the hardware on the windows (the clips on the outside or the eyebolt on the sill on the interior.
Make note of the condition of the windows on your home. On the outside, look for signs of wood decay (soft wood). Also check the condition of the glazing putty that holds the glass in place. Glazing putty can dry out and become brittle so it may be cracked or even missing in some places, and of course, look for any broken glass.
On the interior, look for missing hardware and try each window to see how well it operates. There are ropes on each side of the lower window sash that are connected to a counter weight inside the frame of the window. You may find some knuckle head has cut the ropes or possibly they have just worn out and broke over time, so the window will be hard to lift and it may not stay open unless it’s propped with a stick.
Less often found in Iowa are casement style windows. This type of window swings out on a hinge located at the top and bottom of the frame on one side. The window will usually have only one layer of glass and be mounted in a metal frame. Storm windows are not a part of this window.
It wouldn’t be unusual to find that some of your windows have been replaced with newer units. These could be a variety of styles so check our information on later houses to see what matches up for you.
double hung window
casement window
example window label
Goal:
What we want to do is take your existing windows and make them operate smoothly. We also want to restore your storm and screen frames, and repair wood decay and broken glass. Remember, replacing windows is expensive and the amount of energy savings you get is not likely to justify the cost. If we can get the storm windows in working order and do some sealing on the window frame, you can have a pretty efficient and tight window that will look as originally intended on your home for minimal cost. It is possible you may have some windows that just can’t be brought back to life and then you will be looking at doing some replacements.
Solutions:
(Don’t skip a step, you need to start at the top)
- If you have rotted wood and it has not progressed to the point where the window is falling apart, remove the decay and install patches of either wood or catalyzed putty you can purchase at your local hardware store.
- Broken glass and the glazing putty can be replaced.
- Check the local hardware store or Re-Store for hardware to replace any you have missing. You shouldn’t have much trouble finding some that matches.
- Windows that don’t operate well may just need a little beeswax on the frame to help them run smoothly. If the ropes are gone they can be replaced!!! It’s likely the counter weights are still in the window frame. You may have to remove the trim to retrieve them but you’ll have to remove the trim anyway to reconnect the ropes. Again your local hardware store can help with any missing parts. Don’t forget to lubricate the pulley at the top of the window for extra smooth operation.
- Once the trim is back on we can do some caulking on the interior to seal for leaks. Pretty much anywhere that won’t keep the window from operating is a good place to add a little caulking.
- Now let’s get the storm windows working again. If you still have the originals and they’re in good shape you may only need to do some plane work to make them fit easily. Here is your opportunity to add some weather stripping to the storm window to make a seal to keep out those nasty drafts. If your storm windows are missing – new ones could be made http://www.builditsolar.com/
Projects/Conservation/ PaulAcrylicStorms.pdf.
-Video demonstrations coming soon-
Questionnaire
Now that you’ve finished this section, take some time to fill out this questionnaire to assess your home’s windows. Keep it with the other questionnaires to build a resource you can reference when tackling projects at home.
Insulation and Air Barrier
Assess:
(Let’s find out what you have)
Early houses in Iowa probably had very little if any insulation in either the side walls or the attic space. Some may have a couple inches of vermiculite or rock wool in the attic (If you think you might have vermiculite insulation follow this link for more information: http://www.epa.gov/retailindustry/buildings/insulationbrochure2-1.pdf). If there was any insulation in the side walls it would most likely be rock wool on a paper backing. If you see any other type of insulation (fiberglass, cellulose, etc.) it would have been added at some time after the house was built.
A peek in the attic will tell you what you have. Be sure to look all the way down to the bottom because you may have a couple different types of insulation that have been added one on top of the other. Measure the thickness of each layer so we can determine the R-value of the whole insulation job.
While you’re in the attic let’s look for signs of an air barrier. One place to check is at a location of a light fixture on the ceiling below. Pull the insulation back and see if you can see light or feel air coming from around the electrical box. It’s a good bet you can. Make a note of what you observe.
The walls can be a little more difficult to determine what you have. Here’s a couple of things you can look at to help. From the attic, sometimes you can see into the wall cavity near the roof edge. This can be tough to get to especially if you have to crawl through the attic insulation. Another way to check is remove an outlet cover on the exterior wall. Sometimes there is extra space around the plaster where the electrical box pokes through and you can see into the wall cavity. This is also a good place to check the air barrier. You may be able to feel air movement around the outlet box but not necessarily. Sometimes a foam gasket has been placed behind the outlet plate cover to help stop a drafty outlet. Lastly, in a closet or some other inconspicuous area, remove a baseboard and cut a small hole in the plaster behind where the base would be to have a look.
Let’s also take a look at the boxing or rim joist area (framing area on top of the basement wall) in the basement. This area is exposed to the outside too. It’s pretty rare that this would have been insulated originally and many times is overlooked when insulation improvements are made. Make a note of what you see. Check for an air seal in this area too. Gaps may have been caulked but it’s pretty rare to see that.
While we’re in the basement you will note that the walls and the floor are not insulated. Okay, maybe the walls have something but unless it’s a finished basement I bet not. If there is a crawl space take note of the floor especially, it may be dirt.
Now you know your type of insulation and the amount let’s figure your R-value. Use the chart below to calculate your R-values in the walls, ceilings and boxing/rim joist.
rock wool insulation
outlet gasket
uninsulated rim joist
| Material | R-value (per inch) |
|---|---|
| Vermiculite | 2.1 (asbestos based product ) |
| Rock Wool | 3.3 |
| Cellulose | 3.7 |
| Fiberglass (loose) | 2.5 |
| Fiberglass (batt) | 3.1 |
| Spray Foam | Seek a professional! (there are other issues here) |
*Vermiculite can be tested for asbestos at the University of Iowa lab.
blower door
infrared camera image
Testing:
There is some testing you can do to help determine how well your house is insulated and sealed. One – you can have a blower door test done on your home (do not do a blower door test if you have vermiculite in your home since this is an asbestos based product). An energy rater usually does this; preferably a HERS certified energy rater. The blower door (an insert temporarily installed in an exterior door frame with a high volume fan attached) will pressurize your home and accentuate the air leaks. Just feeling around outlets, doors, windows and plumbing pipes you can find many of the air leaks in your home. A smoke tool can also be used to visually see the leaks when the smoke is released near an area you’re checking. The rater can also run a calculation on your home to determine how much air is leaking from your home. This measurement is in Air Changes per Hour (ACH). There are two numbers you can get, – one is ‘ACH natural’ which is the amount of air that exchanges in your home without any fans or other pressure. This is not the best number you can use; a better number is ‘ACH 50’. This is the number of air changes in your home when it’s under pressure with the blower door fan. If you want, most raters can tell you approximately how big a hole you would have in your home if all the air leaks were put together in one place. Don’t be surprised if is pretty big, like a hole four foot square.
The second test can also be done by your certified HERS rater (ask for a copy of their certification certificate). This test uses an infrared camera to show images of temperature differences in the walls and ceilings of your home. The images will help you determine weak spots in your insulation. Copies of the images will be useful as you make improvements to your home. It’s a good idea to have the rater help you interpret these images because sometimes they show weird things like your silhouette on a window. It also is best to do this when there is a large temperature difference between the inside and outside of your home.
Lastly, ask the HERS rater about combustion air for your furnace, water heater and any other appliance in your home that burns fuel. Your home may leak air enough to feed the flame and draft the flue pipe but as you seal up your home this could become an issue. Talk about your plans to improve the insulation and air seal. Find out how they would like you to monitor your combustion appliances as you tighten up your house.
Goal:
Ultimately we want to have a tightly sealed building envelope with an adequate amount of insulation. Here we can work with numbers; let’s aim for a building with an air change per hour of 3 ACH 50 or less. This would be a very tight building and will require some effort to achieve. On the insulation side let’s try for an R-15 on the basement walls, an R- 20 on the other exterior walls and boxing areas, and an R- 60 in the attic. We’re not kidding when we say if you can get to these goals, you will be living in a very efficient house, an extremely efficient house, maybe the best house on your block. We should pause and think about this a little because it sounds like a lot of work. What is the benefit of going to all this trouble? Well, if we spend our time and money on doing this right, of course our energy bills should be lower; that’s good. We also can use smaller equipment to heat and cool the house, which is also good. But let’s think bigger…. Everyone who follows you, as an owner of this home, will benefit in lower operating costs and no matter what energy source is used in the future, this house will demand less from our planet. Now I’m feeling good!!!
If we’re going to do this right we have to think about a whole slew of other projects: Siding, duct work, wiring and plumbing, bath vents, door and window seals, indoor air quality, back drafting and more. In the big scheme of things, insulation and sealing may be a project that comes later down the road. It’s always temping to take that energy rebate from the utility and blow in a bunch of insulation in the attic right away, but that is possibly the worst thing you could do.
Solution:
So here are the steps, they may not all apply but the order is very important.
Note: If you have vermiculite in your attic, this is a special situation and a trained professional should do all the work!
- We are taking a top down approach so we’re starting in the attic. There are several projects to do before any insulation goes down and we actually want you to take any insulation you have in the attic out! You may be able to roll up the insulation if it’s in batts, but most likely it’s some type of loose insulation. The easiest way to deal with this is to have the blow-in insulation guy come out, reverse the operation, and suck out the insulation (depending on what you have, it may be reusable). Now we have a nice clean attic to work in.
- Any bath or kitchen exhaust fans that are venting in the attic space need to be vented up and out the roof, out the sidewall, or through the eve or overhang. If the overhang or eve is vented, then they cannot be used for venting. All vent pipes need to be sealed and insulated. This prevents condensation from dripping back into the house. Metal rigid pipe is best, metal flex pipe is okay (not great) and please don’t use plastic flex pipe. Seal the joints with mastic (not tape). If you have any plans to add a vent, now is the time to do it. You don’t want to be crawling around in your newly insulated attic messing things up later. The reason we are doing all this is because we don’t want to add any additional moisture to the attic once we’re done; which air leaks will do.
- Next, any plumbing vent pipe coming through the attic needs to be checked out. Hopefully they are in good shape but if not, they need to be replaced now. And the new pipe needs to go through the attic floor (the ceiling below) so we can make a good seal around it in the attic space. Here comes a special secret detail – as the plumber is fitting the pipe, before he attaches it to the pipe below, slip a piece of rubber roofing with a hole cut in it over the pipe that will act as a gasket. Once the pipe is attached, slide the rubber down to the attic floor and attach it to the wood plate the pipe comes through. Plumbing pipes move up and down with temperature changes and this seal will stay in place as the pipe moves.
- Look around for any metal pipes coming from below that could be hot (warm) like from a fireplace, water heater or furnace. There is usually a requirement that there be at least a two-inch space around this pipe of non-combustible material. To make a seal you will need to fit some sheet metal around the pipe and caulk it with high temperature caulking. Be sure to caulk the seam in the sheet metal as well. Don’t worry about caulking the sheet metal to anything else. Now you need to build a box or cage of sheet metal around the pipe to hold the insulation back two inches. Note: not all metal pipes need to be treated this way. Some are rated for insulation contact; you will have to determine what you have. If you’re unsure, put in the air space just to be safe.
- There is going to be some electrical wiring in the attic space. It’s possible you may have what’s called knob and tube wiring. It looks like this: You need to have an electrician look this over to make sure it’s still in working order. Under no circumstances should you bury knob and tube wiring in insulation. It will need to be boxed out similar to what you did with the hot metal pipes. So for this reason, it may be easier to replace it with modern Romex wire that can be buried in the insulation. If the knob and tube wiring is in good shape and out of the insulation, leave it be. On another note, since there is often such a mess of wiring in the attic space, it is a good idea to have a certified electrician check this out). Now is the time to straighten up your wiring.
- Recessed lights that have been cut through the ceiling and stick up into the attic space may need to have an airtight box fit over them unless they are in an ‘air tight housing’ (not likely in this situation) This job is best left to a professional. It can just sit there; no need to fasten it.
- Regarding vented attics, see your local building code official. If everything is done properly, this type of an attic should require very little if any venting.
- Prepare the attic access. If we step back and look at how we get into the attic, it’s pretty obvious that it’s just a big hole in the ceiling. You may even have a stair that walks right up there. The first step is to put an insulation barrier around the perimeter of the hole that will hold back the loose insulation and keep it from rolling down the hole. This usually is made of plywood strips about 12” to 14” tall. The second step is to make a cover for the hole that can be sealed and insulated yet easy to remove.
- Here is a biggie and it may need some major forward thinking on your part. If your house is a two story, and the ductwork system that delivers the warm and cool air to the rooms on the second level does a poor job, you may want to have a plan on how to improve that. This plan may include adding ductwork to the attic space that should be installed now. If you are adding ductwork to the attic, all the joints must be sealed with mastic, do not use flex pipe (metal pipe only), and keep it as tight to the attic floor as possible. All attic ductwork needs to be insulated on the outside.
- Now you have an attic that is prepped for a proper insulation job. We’re going to do this in two steps. The first step is to take a bucket of mastic and a brush in your nice clean attic, and brush the mastic on all the seams and penetrations you can find in the ceiling – you’re creating your air seal. This is a really important step –holes that aren’t properly sealed, will leak air that carry moisture into your attic that can cause a number of problems such as condensation, wet insulation, wood rot, water staining, etc. If you have knob and tube wiring, consult your electrician on how it should be air sealed.
- The last step is to finally add the blow-in insulation we wanted to put in way back in step one. Cellulose is the preferred insulation; it’s made from recycled paper, and holds its’ R value well over time. We want to get to an R 60. Notice we’re not talking about how many inches we need to add, that’s because to get the R value we’re after, we need to add a certain number of BAGS of insulation. The bags of insulation have a label that will tell you how many bags per 100 square feet you need to get the R value you want. Make sure your insulator knows you expect X number of BAGS to be installed in your attic (not inches) based on your square footage. Note: you could do this step yourself with some rental equipment but I would check the pricing on hiring the job done; it may not be worth the trouble to do it yourself.
That was intensive to say the least but a job well done!
fiberglass batt insulation
loose inuslation
mastic sealed ductwork
rubber gasket
messy wiring
neat wiring
attic door cover
A special note on attic storage:
Some people really like their attic storage space; we don’t. A modern attic should be for insulation only and if it is sealed and insulated properly, there is no reason you should need to be up there. However some homes do have good attics with floors strong enough to hold a load, enough headroom to stand up in and a decent stair to access it. In this case you should consider insulation in the rafter spaces rather than on the attic floor. There are insulating systems you could use that would do a good job of insulating and sealing the attic rafters and some do not require venting. If your attic is important to you as storage space, a conditioned attic space is what you need.
conditioned attic space
high-density foam board
looking down a balloon framed wall from attic
We are ready to talk about the side walls, and the basement.
Our two objectives here are to insulate and air seal. If you already have some insulation in your walls, even if it’s not as much as you wish you had, you should accept it as it is and focus on more important areas like air sealing. If you do need to insulate, like the attic, there are other things to consider before we get too deep into the project. If you are planning an entire interior renovation with gutting the house on the agenda, you can approach the insulation from the inside in a conventional modern application. If you’re planning on residing your home, there are some added steps you can take for even better results. This is a job you will have to hire an expert insulation installer for.
Here are the steps:
- The first thing you should do is to team up with a reputable insulating contractor who has a variety of products you can select from. Have them out for a look and a discussion about your installation options. Remember those infrared camera images you saved? Now is the time to bring them out. They will first evaluate the exterior cladding on your home. What do you have? Brick, wood siding, stucco, and asbestos are all fairly common on houses in this era. We’ve even seen houses in Iowa that are all concrete. Depending on what you have, insulation could be added from the exterior by either drilling holes in the cladding or removing some of the cladding to access the wall cavity. In the case of brick or possibly even stucco, this may be better done from the inside by either drilling holes in the plaster and patching or removing the base board and installing from there. The two best options for adding insulation in an existing wall are dense pack cellulose and open cell spray foam. Ease of installation and cost can be your guiding factors in which you decide to use.
- If you are planning on residing your house and will be taking off the existing wall cladding, insulation should be a part of that overall project. You will have the added benefit of being able to add a layer of high-density foam board to the exterior that will serve as a complete thermal break (you’ll even have some insulation where the studs are, not just in between). The foam board will also help eliminate some air leaks.
- If there is an option to use an infrared temperature camera as the insulation is being installed, do it. This will help the installer make sure they are getting good coverage in the wall cavities and identify areas that may get missed.
- A thorough insulation job with either the dense pack cellulose or the spray foam will do a lot to slow down the air leaks. There are still a couple areas to address. If your exterior walls sit on the floor system verses going straight through (a technique called balloon framing used in early wood frame houses) air could be leaking in. It’s kind of hard to get to, but if you have an opportunity to get behind the baseboard and caulk the connection of the floor and the bottom wall plate, do it. This may be totally impossible so don’t tear the place apart to get to it.
- You may still want to add the little foam gaskets behind the wall outlets and switch plates but you could wait to decide until after your blower door re-test.
Now to the basement: First a quick note, if you have water problems in the basement, they need to be corrected before any insulating is done.
- We’ll address the floor first – Don’t worry about insulating under the floor unless you have plans to remove it. If you are going to remove it for some other reason, be sure to include two inches of high-density foam board and an 8-10 mil poly (plastic) sheet under the slab. Be sure to tape and seal the seams and edges for radon. Done!
- Dirt floor crawl space – this needs to be addressed. A dirt floor will continuously add moisture to your house (a bad thing) and could be a source of radon gas (also a bad thing). You will probably have to clean up the space, remove broken bricks and junk, and level off the dirt. Add a layer of an 8-10 mil poly sheet to the floor and run it up the side walls a foot or so and seal it to the foundation walls using caulk and cleats. Seal all the seams and penetrations and now add two inches of high density foam board to the floor. Code may require you to cover the foam board with a non combustible material like concrete.
- If you have a crazy rock or stone foundation you may have to get creative on making any type of attachment to it. We recommend calling in an expert.
- Before we insulate the basement walls, caulk the joint between the floor and wall as a radon seal.
- The foundation walls including the walls in any crawl space should be insulated with a layer of 2 inch high density foam board. This can be attached to the wall with a few concrete anchors and washers. Just enough to hold it in place. Now you have a complete insulated thermal break wall.
- Next attach wood furring strips to the face of the foam board with long concrete anchors to the foundation.
- Then hang a layer of ½ inch moisture resistant gypsum board to cover the foam. Stand the sheets upright so the seams are on the furring strips. This has to do with protecting you from flammable material.
- Lastly, have the spray foam contractor come and apply a 3” layer of high density spray foam in the boxing/rim joist area to insulate and seal it up.
Now, if you have addressed your windows and exterior doors (covered in other areas) you are ready to have your HERS rater back to see how you did. During this next testing you need to have your rater run a check on how well your combustion appliances draft; water heater, furnace, fireplaces etc. Because you’ve done such a good job sealing up your home, they may need to introduce make up air to keep from back drafting. This is critical to your safety! Carbon monoxide will be introduced into your home if a combustion appliance is back drafting.
At this stage, it is important to consult with a certified HERS rater or an HVAC professional to design a ventilation system to provide good air quality. This may include additional exhaust fans or a heat recovery ventilator.
This may seem crazy that we worked so hard to seal up the house just to bring in outside combustion air and additional ventilation. The important thing is that you are now in control of how much and where that air comes in. Good Luck!
spray foamed rim joist area
Questionnaire
Now that you’ve finished this section, take some time to fill out this questionnaire to assess your home’s insulation. Keep it with the other questionnaires to build a resource you can reference when tackling projects at home.
Heating and Cooling
Assess:
Let’s head for the basement. In most homes the basement is the location of the heating equipment and the ductwork. It’s likely that what you will be looking at is not the original stuff installed in the house.
Most homes in Iowa before 1940 would have had a large unit that burned coal or possibly wood. You may see a steel door in the foundation wall that’s about two feet wide by a foot and a half high. That’s the coal chute door where coal would have been shoveled into the basement. The coal would have then been burned in the furnace to provide the heat. Often from this large unit there would be a spider web of round ducts that would feed the heat to each room in the house. If the house is a two story, the upper level (bedrooms) may not have been heated at all. There are stories about people who slept in these rooms growing up, waking up in morning with frost on the blankets. You may also see signs of a place near the furnace where there was a hole in the floor above. It would have had a wooden grate on it to let air into the basement. This system was called a gravity flow system: the warm air would rise up through the ductwork and the cool air would fall to the basement through the floor grate, no fan like in modern furnaces.
It’s possible you may have had a fuel oil burning furnace instead of coal or wood. In this case there would have been a large tank in the basement to hold the fuel oil and a connecting pipe to the outside that was used to fill the tank. Sometimes these tanks remain in the basement even though they are not used because they can be difficult to remove. The ductwork system would have been similar to what we described above.
A third possibility would be a boiler. In this system, water would have been heated in a tank (with coal, wood or fuel oil) and sent through piping to radiators in the various rooms of the house. No ductwork. A two story house with this system might have been lucky enough to have heat in the bedrooms on the upper level. The radiators would be large metal objects in each room that look like…..well they look like big accordions.
Later homes may have had the first gas or propane burning furnaces. These units would be large by today’s standards in both the amount of heat they produce and their physical size. The ductwork system would not have been much different though.
In houses prior to 1940, the air conditioning would have been an open window. That’s it!
What you have now is probably different than what was originally in the house, but if you look closely, you should be able to determine how the house was heated when it was first built.
What you see now is probably a new heating unit (furnace) fired by natural gas or propane. It may be hooked to some new ductwork but probably still uses a lot of the old pipes. If the house originally had a boiler, it’s possible there would be a new boiler but the rest of the system, the piping and the radiators, may still be in use. Make a note of what you think is original and what has been replaced.
There are a couple of questions to consider as you are looking at your current heating and cooling system. Before you even think about replacement units, consider safety first, especially if you’ve had headaches or flu like symptoms and if your house is not all electric, have a professional contractor check the back drafting throughout your house, especially if you have added any new fans in the bathroom, kitchen or elsewhere.
1. How old are my heating and cooling systems? If your furnace or air conditioner is over 20 years old, you may be on borrowed time. Replacements are probably in the near future. Its not always the unit in the basement but its the exhaust pipe or pipes within an old chimney or hidden within the walls that may be failing which can be very dangerous. If you see holes in any exhaust pipes or a tin plate looking thing on the wall, please seek a professional contractor.
2. Are my heating and cooling systems energy efficient? This may be kind of hard to determine. If you have done improvements on the building to make it tighter and more energy efficient, and you are dissatisfied with your energy bills, you should look at what a new unit would do for you. Your energy costs can be calculated (estimated) with a new unit so you can compare. A heating and cooling contractor can help with this. There is more useful information to follow regarding how to figure this out.
3. Can I be comfortable in every room in my house no matter what the temperature is outside? It’s not uncommon to have rooms that just never get very warm or an upper level rooms that are hard to cool. This has more to do with your delivery system (the ductwork or piping) than the furnace or air conditioner.
coal chute
Testing:
That was the fun part, now for the not so fun but extremely important part – making sure the system is operating safely. Note – you cannot do this yourself; you have to have a professional inspect your system to make sure it’s operating as it should be. When we burn fuel inside our home (or anywhere for that matter) it gives off carbon monoxide. This is dangerous stuff and all of it needs to be vented to the outside. Your heating and cooling expert will check for proper combustion and venting to make sure your system is not letting any of this dangerous gas mix with the air you breathe inside your home. We can’t stress how important this is – it’s a matter of life or death. If your heating and cooling contractor is saying things about a cracked heat exchanger or back drafting you need to listen up and take immediate action.
It’s a good idea to have your system checked each fall before heating season to make sure it’s working properly. If you have central air-conditioning you should have a check done in the spring also just to make sure it’s working at its’ peak efficiency.
One thing you should have completed is the energy load on your home. What you want to know is how many BTU’s (British Thermal Units) of heat it takes to keep the inside of your home at 68 degrees when it’s 6 below zero outside, and how many BTU’s of cooling does it take to keep the inside of your home at 78 degrees when it’s 98 degrees outside. These temperatures are commonly used here in Iowa and you can adjust them to something more suitable to you but be careful, the idea here is to be able to properly size your equipment not oversize it. When we oversize the furnace and air conditioner it will become less efficient to operate. If we under size it we may not be comfortable in our home. Note: it’s pretty rare that equipment gets undersized by any heating and cooling contractor.
How do we go about getting this information you ask? It’s relatively simple; you ask your Heating and Cooling contractor for a ‘manual J’ calculation and if they look at you funny you may want to get a new contractor. A good one will ask for some information about your home and you will have most of it because you’ve already inspected and improved your insulation and windows. You also had a blower door test done so you know your air infiltration rate. Here’s what information will be needed:
- Square footage of each level of your home including the basement
- The ceiling heights of each level (we’re figuring out the volume of your home here)
- The square footage of the glass area on each side of the house labeled East, West, North and South and the U value of the windows.
- Square footage of exterior doors and what they are made of.
- How the exterior walls are built starting from the outside to the inside. Be sure to include the R-value of insulation in the walls as well as the finish and structural materials. Remember the basement walls; they will be different than the above grade framing.
- The R-value of the attic insulation and how the ceiling is built, i.e.: plaster on 2×6 ceiling joist spaced at 24 inches. (lines 3,4,5 and 6 above will help calculate the thermal resistance of your home)
- Lastly the air leakage figure. ACH50 (from your blower door test)
From this information the energy load in BTUs for both heating and cooling can be calculated. This is a constant figure and will not change unless you do something to the building envelope. This is also how you size the furnace and the air-conditioner to fit the loads on your home. You see now it becomes apparent why we do the insulation, windows, and air sealing before we put in the new furnace and AC. Our improvements to the house have affected the heating and cooling load; the better our improvements the lower the loads thus the smaller the equipment. LOOK, LOOK, we’re saving dollars not only on our energy bill but on the cost of installing the new equipment too!!!
There are some other tests that can be done on your heating and cooling system that will help you know how effectively your equipment is working.
One that you can do is measure the temperature in each room to get an idea of how even the heating and/or cooling is. Ideally you would check the heating system on a cold winter day and the cooling system on a hot summer day. Be sure to note the outside temperature along with your other readings.
You’re heating and cooling contractor or energy specialist can also check the airflow if you have a forced air system (the big blower fan in the furnace). The two areas to have them check are 1st, the airflow on each side of the furnace filter, and 2nd, the airflow at each register. This is important because restricted or poor airflow can greatly reduce the efficiency of your equipment and the comfort level in the house. We need to talk a little here about the air filter. Most systems will have a disposable filter like the type you buy at the big box store. Some of these are sold as super allergen dust busting mega great filters and they probably are. The thing is they could be screwing up your airflow in the ductwork so badly that your fan can hardly push the air through it. The best thing to do is use a cheap, fiberglass mesh filter and change it often (once a month or month and a half). There are filter systems that you can add to your ductwork system that are electronic or have large pleated filter material. You may want to consider a filter system like this especially if there is someone in the house with allergies. The important thing to remember is no matter what filter system you use there needs to be adequate airflow across the filter to provide the needed air to each room and keep the fan running at peak efficiency. (include pictures of different filters)
The super duper filters usually have a MERV rating. MERV 8 is good, MERV 10 better and MERV 13 or above is best. While the contractor is testing airflow, this would be a good time to try a couple different filters; all must maintain proper airflow from the furnace fan.
Goal:
Once we are sure everything is working safely (our number one priority) our goal should be to have comfortable rooms (temperature wise) throughout your home at a reasonable expense. This may mean adjustments in the ductwork using your existing equipment or maybe replacing some outdated equipment with newer more efficient units. Or maybe everything is dandy for now and you can look at this when the furnace wears out later.
Solution:
It can be very confusing to upgrade a heating and cooling system. Probably the biggest mistake that‘s made is assuming that a new furnace or air conditioner will solve all your problems. The distribution system (the way we are going to get the heat or cold to all the rooms in the house) is equally important and maybe even more so.
Heating and cooling improvements are not a do it yourself project and need to be done by a qualified heating and cooling contractor. Having said that, there are some steps to be taken that will help make sure you get a good system.
Since most heating and cooling systems in Iowa consist of a ductwork system connected to a forced air furnace with an air conditioner unit attached, we will proceed with this type of system in mind. If your heating and cooling system is different, there is still a good deal of useful information you can use so read on.
- Keeping in mind the proper order of things, you should have done your window, insulation and air sealing improvements first if possible.
- Have the load calculations figured for your house, preferably with required BTUs and cfm of air for each room, both heating and cooling.
- Have your temperatures of each room for both heating and cooling available.
- Test your ductwork system for airflow efficiency. This would be an opportunity to see how your filters affect your airflow. You may want to have a couple different ones around to try.
- Adjust your room registers to balance the airflow.
- If you feel there are problems in the air delivery, they should be addressed now. This can require some creative thinking by your heating and cooling contractor.
- Once you are satisfied the ductwork is capable of handling your comfort needs, then you can start looking at upgrading the furnace and AC units if you want.
Now let’s talk about the heating and cooling equipment.
- The first and probably only step is selecting your equipment. This is not an easy decision but we are here to help. Lets walk through some of the options.
| Central air and air sourced heat pumps | Furnaces – gas, fuel oil and propane | Boilers – gas, fuel oil and propane | GeoThermal closed loop | Mini split | ||
|---|---|---|---|---|---|---|
| Good HVAC | Cooling | 13 SEER | N/A | N/A | 14.1 EER | N/A |
| Heating | 8.2 HSPF | 90 AFUE | 85 AFUE | 3.3 COP | N/A | |
| High efficiency HVAC | Cooling | 14 SEER | N/A | N/A | 15.5 EER | 17.8 SEER |
| Heating | 8.6 HSPF | 92 AFUE | 87 AFUE | 3.6 COP | 11.3 EER | |
| Very high efficiency HVAC | Cooling | 15 SEER | N/A | N/A | 17 EER | 20 SEER |
| Heating | 9.0 HSPF | 94 AFUE | 90 AFUE | 4.7 COP | 11.8 EER |
outside AC unit
furnace
geothermal
Pros and Cons of each heating and cooling system:
Gas, propane or fuel oil forced air combustion system
Pro: quick temperature recovery, inexpensive equipment, can retro fit into most homes with a ductwork system
Con: combustion fuel source of Carbon Monoxide (CO), dirty, fuel price fluctuates
Central air conditioning with a frame coil and exterior compressor
Pro: can be fitted into existing forced air heating system (uses the same ductwork), whole house coverage, quick temperature recovery, contractor friendly since this is the most prevalent system
Con: susceptible to dirty environments (leaves, dirt, sticks) so requires occasional maintenance
Boiler radiant heat (combustion fuel boiler with piping to radiators)
Pro: quiet ‘soft’ heat
Con: cannot accommodate a cooling system, slow response times
Electric resistance heat-radiant (base board heaters, radiant ceiling panels, heated floor.)
Pro: in the case of baseboard heating, it’s cheap and easy to install & you can put controls on each unit for easy zoning, simple design with not a lot of complicated parts, electricity can be produced in a number of ways, and it will almost certainly be a fuel source we will have years from now
Con: electric heat is usually expensive, cannot accommodate a cooling system, can be cost effective with an all electric rate (see your utility provider), also suitable for air source and mini split heat pump back up
Ground sourced heat pump (geo-thermal) heating and cooling
Pro: electricity can be produced in a number of ways and will almost certainly be a fuel source we will have years from now, AC and Heating come from the same unit, equipment is inside & out of the elements, equipment is the highest efficiency of all possible units, cost effective with rebates and tax incentives, can also produce hot water
Con: can have slow recovery
Mini split heating and cooling
Pro: very efficient, can heat and cool, fairly easy to install, can be used in small spaces such as additions as an additional heating and cooling source, easily used for zoning, can be cost effective, good for remodeling since no ductwork is needed
Con: may need several units to do an entire house, some installations look like window AC units (visually more dominate)
These are a few of the most common heating and cooling systems offered here in Iowa. There are others but be wary unless you have a trusted energy specialist working with you to evaluate the system and how it will work in your particular situation. There is a lot of weird stuff out there and not all of it is worth your time, trouble and money.
Questionnaire
Now that you’ve finished this section, take some time to fill out this questionnaire to assess your home’s heating and cooling. Keep it with the other questionnaires to build a resource you can reference when tackling projects at home.
