Tag Archives: efficiency

Save Cash, Reduce GHGs and Save the Planet

Reduce energy bills, reduce GHG emissions, save the planet

Can you help save the planet and gain a dollar advantage at the same time? Are you concerned about global warming, air pollution or just your energy costs? Here is a list of things you can do to your home which can cost little and have excellent returns. The list starts from the least costly and is suitable for existing housing.

Typical costs are based on a specific Canadian location in Canadian dollars. They could vary widely. Do your own research and calculations.

Caulking, a cheap way to help save the planet.

Caulk everywhere there is any chance of air leakage

Number one. Caulk, caulk and more caulk. Whether you live in a heating or cooling climate, air leakage is a large energy cost. Caulking is cheap, typically a couple of bucks per tube. Watch for sales. Use paintable or clear product that is suitable for indoor or outdoor use. Fill every crack and space that has even a remote chance of air leakage. This has the added advantage of reducing hiding spaces for insects. If cracks are large, repair or stuff with a suitable material before caulking. Typical cost $10 to $50. The short course on caulking.

Angie changed the 312 furnace filter
Collin Anderson / Foter / CC BY

Number two. Maintain your equipment. Keep furnaces, air conditioners.refrigeraters and freezers operating at peak efficiency by cleaning heat exchangers and changing filters regularly. Anything that looks like a radiator and has a fan needs to be kept clean as well as any radiating surface. Use metallic tape to seal any leaks in ducting. Arrange furniture so that it has a minimal effect on heat distribution and does not block ducts. Do not install restrictive filters in an attempt to clean the air. They effect efficiency and can damage a furnace. Good maintenance reduces replacement costs. Typical cost for filters is about $25 for a year in colder climates. The best furnace filters to buy.

Keeping your furnace clean can help save the planet
Keep your furnace cleanslworking2 / Foter / CC BY-NC-SA

Number three. Use less cooling or heating. Turn the heat or air conditioning as low as possible if no one is going to be home. Lower the temperature at night in cool climates and use more covers on the beds. Turn heating and cooling completely off if there is no possibility of freezing or other damage. You can do this manually or you can purchase programmable thermostats (or smart controls) that will allow you to raise or lower temperature just before you need it to prevent temporary discomfort. Typical cost $0 to $100. Learn more about thermostats.

Number four. Use less lighting. Make certain everyone in the house turns off lights when not needed. Replace bulbs as they burn out with lower wattage bulbs or replace high usage bulbs immediately with LED or CFL bulbs. Prices are still fairly high for more efficient bulbs but in

LED lights can help save the planet.

LED lights are the new efficient lighting.

many cases the payback time is very rapid. I just bought 4 Led bulbs. 2 were 6w to replace 40 watt and 2 were 10.5w to replace 60w incandescents. My total cost including taxes was $60. You can likely find them for as little as 1/2 that. Pretty pricey but I did a calculation for one much used light. At 6 hours use per day the LED would pay for itself  in 1.5 to 2 years. that’s a good investment in my book. Our electrical rate is $.08 right now and higher rates would effect a higher return. I am very impressed with the LEDs. They are practically instant on. The light is pleasant and at least as good at replacing incandescent as advertised. A 10.5 watt actually gives as much light as the 60w it replaces. Typical costs $0 to $500. I tried to find a good link to information about LED bulb. Everything I could find was outdated. Development in LED technology is proceeding at a lightning pace

Baths use a lot of hot water
Baths use a lot of hot waterwester / Foter / CC BY-NC-ND

Number five. Use less water and heat less water. Showers typically use much less water than baths. A shower can be installed in most bathrooms for as little as $200 if you do it yourself. A new bath spout with a flex hose and shower head along with a shower curtain may be all you need. A tub surround or tiling may be needed as well in other cases. A lot of energy can be saved by doing laundry in cold water and drying you clothes on an outdoor clothes-line when weather permits. A more expensive option is a front load washer. It is worth considering if you have a large family and are replacing your existing unit. When replacing water heaters, consider high-efficiency models. There is really not a typical cost here but some options cost practically nothing while others can run into the thousands.

Sufficient attic insulation can go a long way toward saving the planet.
This attic obviously does not have enough insulation for cold climates.zieak / Foter / CC BY

Number six. Increase attic insulation. In many heating or cooling climates, attic insulation up to about R60 is cost-effective. Have a look. If you have less than 16 inches of insulation you likely have room for improvement. Although a bit of a pain, do it yourself installation is not difficult. Adding 10 inches of loose fill insulation to a 1000 sq. ft. attic can cost under $700. This is an increase of about R30. 

Insulate your basement for heating efficiency..
Insulate your basement for heating efficiency.Paulgi / Foter / CC BY-NC-ND

Number seven. Basement insulation is important and inexpensive if the space is unfinished. Often neglected is the at the top of walls between floor joists. Insulate to at least R20 and pay close attention to sealing against moisture on the inside. There are several different possible methods of insulating this area with wide range of efficiencies and cost. Necessary in any cold climate but probably not effective in a hot climate.

To help save the planet use use energy efficient windows when replacing.
Choose energy efficient windows when replacing your old ones.Joe St.Pierre // Joestpierrephoto.com / Foter / CC BY

Number eight. Replacing old windows and doors with new and more efficient ones. This is one I don’t recommend for energy-saving reasons alone. It is very costly and the payback is long. However, if you are replacing for appearance or for functionality, use at least a double paned glass with low E coating. Vinyl or wood frames allow the least energy transfer.

These last two may be out-of-order but costs can vary from very little to very much so I have placed them at the last. They are not always a possible solution in all situations

 Orient your house to take advantage of the sun or shade
Foter / CC BY-SA

Number nine. Consider your home orientation to take advantage of natural, passive heating or cooling. This is easier with a new house, but use of awnings, heavy drapes or cross ventilation can be effective with older homes.

Trees can go a long way towards saving the planet
Trees can go a long way towards saving the planetblmiers2 / Foter / CC BY-NC-SA

Number ten. Use trees for shading and wind breaks. They also tend to lower the temperature in their immediate vicinity on hot days. They have the added advantage of removing carbon dioxide from the atmosphere. The result is stored carbon and released oxygen. In my area winters are very cold and the prevailing winds are from the north and west. I would plant evergreens to the north and west for windbreaks and deciduous trees to the south for summer shade while allowing sun through in winter. Varieties require careful consideration. Planting large trees can be very costly but  some varieties grow rapidly and can be used while waiting for slower growers to mature. Time is rather irrelevant here as it is the future we are trying to save. Facts about trees.

You can do your bit to reduce greenhouse gas emission and pollution while padding your pocket at the same time. It doesn’t matter if you believe in global warming or not. The cost of fossil fuel and thus energy is bound to escalate in the future, perhaps rapidly. The Idea that recoverable reserves have increased due to technology is misleading. Oil prices have increased 10 fold in recent years in spite of increasing production. We may not be in danger of running out soon, but costs are increasing rapidly.

You may notice that I have not included any alternative power options in this post. That is because it is pretty complicated, especially in our northern climate. Regulations for connecting to the grid vary widely as well. The economics requires a detailed study for each situation. It deserves a post of its own, and I don’t feel qualified to write one, until I have completed a lot more research.

Share this:
Share this page via Email Share this page via Stumble Upon Share this page via Digg this Share this page via Facebook Share this page via Twitter

An Efficient House

If your goal is to build an efficient house the devil is in the details.

L'il Devil
Darwin Bell / Foter.com / CC BY-NC

Not paying close attention to the little things can result in a lot of little inefficiencies. if you expect the lifespan of a house to be in the 200 year range, these little inefficiencies add up to a lot.

The main concern here is energy efficiency, but I also want to touch on construction efficiency and on living efficiency. By living efficiency I mean time, money and effort spent on maintenance as well as everyday cost in time and effort.

One of the factors I have probably mentioned too many times already, is size. It is only common sense that a larger home is going to be less all around efficient than a smaller one built to the same standards. If prestige is the goal, my feeling is that there are far better ways to gain it.

Very careful planning is where efficiency starts. Use care and common sense in evaluating your needs. Think into the future. Are you building space for children that will be gone in a couple of years? Are you considering special needs you may face as you age.

Swain House, Fort Street, Detroit
Not so simplesouthofbloor / Foter.com / CC BY-NC-ND

Keep it simple. Complicated designs tend to have higher costs and contribute to both energy and construction inefficiencies.

A simple rectangle is the most efficient design for energy efficiency. It provides the most space with the least exterior surface.

The insulating value of the walls and especially the ceiling is very important if you live in a cold or hot climate. If you are lucky enough to live in area where daily average temperatures stay in the comfortable range then thermal mass is probably more important. The ceiling is easier to insulate to higher R values and has a reasonable payback even to R50 and higher. Most homes have a certain amount of heat layering which increases the temperature differential between inside and out at the ceiling and the tops of walls. More insulation is required at these locations for the same results. Blow in insulation works well. Normal rafter configurations make the area above exterior walls difficult to insulate well. Special rafters with a raised “heel”  solve this. The extra cost may be worth it. How to measure heel height.

Rafters today are usually manufactured trusses which are enable fast and efficient construction. Click here for a truss diagram and a glossary of terms. A n excellent and more detailed explanation of trusses is available here.

When calculating paybacks it is important to remember that fuel and electricity will likely become more expensive in the future. This will be partly because of scarcity and of environmental concerns.

Heat in the attic is not your friend no matter what your climate. Be certain of good insulation and ventilation. Choosing a light-colored or reflective roof covering could be beneficial.

192/365 - Help, I'm Alive, My Heart Keeps Beating Like A Hammer
Helga Weber / Foter.com / CC BY-ND

Even the best windows have poor insulating properties. Design with this in mind. Don’t neglect the use of natural light for energy savings.

A two-story house or a basement can add living space  at a lower energy cost. Providing staircases can reduce this benefit considerably. Stairs can be problematic for small children and seniors. There is an element of danger to everyone. My own opinion is that it is best to avoid the risk of falls if possible.

One of the most common housing problems I have encountered over the years, has been wet basements. Providing a full depth basement that is completely waterproof may be more costly than the space is worth. This link is to a commercial site, but they do list a lot of the common basement problems.

An efficient house must be as impervious to air movement through the exterior envelope  as possible. Pay extra attention to sealing around windows and doors. Don’t forget to seal where plumbing and wiring penetrate the building envelope.

Energy efficient lighting is a consideration. Flourescent and LED lighting uses less electricity than incandescent. In a climate like much of Canada it becomes a little more complicated. incandescent bulbs lose efficiency by generating heat. In winter, in Canada, that heat is definitely not wasted. In summer the days are long and little light is needed. Other considerations are how that electricity is generated and what fuel you use for heating. My own guess is that  the extra cost of flourescent or LED bulbs may not be justified in all cases. Our government here is taking the decision out of our hands by prohibiting the sale of incandescent bulbs. Probably an effort to make Canada look better to the rest of the world through climate change action. Follow your own consience.

an efficient house has efficient appliances
Corie Howell / Foter.com / CC BY-NC-ND

Choose energy-efficient appliances.  Front loading washers are presumably more efficient than top load. The capital cost, however, appears to be almost double. They do use less water and the cost to heat that water is, of course, lower. There is little reason to heat the water to wash clothes, though, so much of the advantage is lost. I think the jury is still out on this one.

A clothesline is an inexpensive way to use less electricity

A garage may seem like a bit of a luxury. Actually a lot of fuel can be saved by not having to warm or cool your vehicles by idling. An attached garage has at least one less wall for heat loss. There is no reason to heat a garage above 40 degrees fahrenheit. The latent heat of a vehicle just off the road is enough to provide most of the heat needed for a well-built garage. In hot climates, just keeping the sun off your car makes a huge difference.

Design your house for safety and ease of use. Make certain that bathrooms are easily accessible from all areas, Kitchens must be designed to reduce workload. Large closets are good in the master bedroom, but do you really need them in guest rooms? I never could see the logic of two sinks in a bathroom. Do you really want to carry togetherness to that extent.

Minimize hallways. They are largely wasted space. Do not use doors where they are not necessary.

Place windows higher for privacy and to maximize space for furniture.

Do not use more interior walls than you need. An open concept is efficient and pleasant.

Vaulted ceilings add interest and an illusion of space, but are not very energy-efficient and may make your home more difficult to insulate well.

To reduce the environmental cost of building your efficient house, there are a few considerations. Cement and steel are huge greenhouse gas producers so it follows that they should be used carefully. Calculate carefully so as to not waste concrete. Building on a crawl space reduces the need for concrete and reinforcing steel considerably. Both products have a long life and this reduces impact somewhat. Review each material and design choice for its energy use and environmental impact. Environmental cost of building materials.

Source as much of your material as possible locally, to reduce the impact of transportation.

Last House on Holland Island, May 2010
An unsafe locationbaldeaglebluff / Foter.com / CC BY-SA

Build strong and build in safe locations. Replacing or repairing homes damaged by flood or storm is not very efficient or environmentally friendly.

Use labor and trades that are nearby if possible. If doing much of the work yourself, see if it is possible for you to live on site during construction. This is a huge time and energy saver.

Choose your water and space heating equipment carefully. Eliminating a chimney saves considerable space and material. consider the space used by the equipment. Using a tankless water heater for both space and water heating eliminates the need for a chimney and much of the space requirements. Follow the following links for more information. Hydronic radiant heatingHeating with a hydronic radiant system.

Finally, the home that has a long practical use is more environmentally friendly, So build well and with forethought. Avoid fads.

Share this:
Share this page via Email Share this page via Stumble Upon Share this page via Digg this Share this page via Facebook Share this page via Twitter

A Nearly Finished Home

Our nearly finished home

Our home

Gage, the super, is checking my every move.

We now have a nearly finished home. It has been a bit of a strain on this old body but we were able to move in before winter. There is still quite a bit to do but the pressure is off.

Changing seasons

The scenery changing with the seasons

For those of you who live in more moderate climes, we had our first snowfall a few days ago (Oct.28). The temperatures at night are fairly consistently below freezing, with the lowest to date about minus 14 celsius. That is about 7 degrees fahrenheit. Our somewhat unconventional heating system worked perfectly through this first test. Of course, the house is super tight, and super insulated, so it requires very little heat. In fact, we were heating with only a small electric heater until we had our gas hooked up, less than 2 weeks ago. It was always comfortably warm.

Bedroom

We have a bed room

Our bedroom is nearly finished. We went outside the box a bit, and installed a chandelier.

We had one of our unforeseen delays in acquiring our gas service. Apparently, the gas company had a major outage and were short of staff. It took nearly two weeks, from the time I requested service, until the meter was installed. It was fortunate that everything worked when we started it up.

I promised to report on the results of my ceiling stippling job. I thinned drywall mud to the consistency of thick paint, and applied it in about 5 ft squares with a long nap roller. Stippling was done by pushing a special brush into the mud. After a few days drying, I primed and painted. The end result was satisfactory but not as perfect as I would have liked. The drywall joints should have been finished just a little better. The  joints are slightly visible when some lights are on, and should have been finished to nearly the same degree as required for painting. It is obvious that this is not a method to hide large flaws in your finish. It does, however, avoid the problems inherent in painting a large flat ceiling. Overall I am happy with the results, of this, my first attempt

A stipple ceiling

My stipple job

Stomping brush used for stipple

Stomping brush used for stipple

The brush used for stippling is sometimes known as a stomping brush. They are available in a few different configurations, such as rosebud or crowfoot, which can be double or single. I had a little difficulty finding one in Canada, as this is a method seldom used in this area.  Lowes was the only retailer I could find that stocked one. I was able to order via the internet. They may be more available from drywall distributors.

Most of my final inspections have been done. Everything passed with only a few minor changes.

I had originally planned on two water heaters for potable and heating, but research, and a few other concerns, convinced me to use one heater with a heat exchanger instead. Since the Navien NP-240(A) I am using is rated at an input BTU of about 200,000, there is no shortage of capacity.Because of a lack of experience, I chose to oversize the heat exchanger. The extra cost was insignificant. Unlike other types of heating, the over sizing of components has an insignificant  effect on fuel efficiency. I will dedicate a future post exclusively to this type of heating. I will add that I am sitting at my computer this morning with bare feet. Very comfortable.

Heating and hot water

This provide all our heat and hot water

I installed a circulator in my potable hot water system. This provides almost instant hot water to sinks and showers. This allowed me to use 3/4 inch water lines to all branch offs. This means that if you are in the shower, and somebody opens a faucet, there will not be a shocking change in water temperature. Although there is some energy cost ( reduced by insulating all hot water lines), there are significant reductions in water wastage.

Heat exchanger and watercirculators

A look at part of our system

Gage has a girlfriend who comes to visit and to go for a walk everyday. That’s her staring at the camera. Her name is Lulu, and the only things she likes better than Gage, is her “Mom” and food.

 

Friends

Gage the supers girlfriend

 

 

Share this:
Share this page via Email Share this page via Stumble Upon Share this page via Digg this Share this page via Facebook Share this page via Twitter

Size Matters When Building Your House

Size matters to the planet and to your wallet.

when size matters
RowdyKittens / Foter.com / CC BY

Is it practical to reduce the size when building your house? Does a smaller car make sense?

As you may know from previous posts, we have been living in a in a motor home for the last six weeks, as we get a start on our new house. This isn’t a new experience. We recently lived for an entire year in motor homes while traveling. It has given us a perspective on what our real need for space might be.

For an excellent photo essay about a tiny house, follow this link

Of course a motor home is not exactly a house. If you don’t like your neighbors, the climate is unsuitable , or you want a change of scenery, it only takes an hour or so to pack up and move. This will be the first time we are permanently (for the summer) in one location.

There are quite a number of people experimenting with permanent RV living. Often they are snow birds, who move to more pleasant climates as the seasons change. Of course this option is rarely open to people with children or jobs. It does serve to illustrate that there is a large proportion of the population who do not really need houses at all.

Over time, many of our wants seem to become needs. Only by doing without, do we really find out if we miss things or not.

size matters to the environment
ecstaticist / Travel Photos / CC BY-NC-SA

Our current living space is less than 8 feet wide and about 35 feet long or about 275 sq. ft. (26 sq. m.). Is this livable? Yes it is. It is even quite comfortable as long as we have some extra storage and outdoor living space.

Disadvantages? Well, our hallway is 22 inches wide, which is just over my shoulder width, so passing each other is a squeeze. Space around our double bed is quite limited, which makes getting in and out awkward. Getting dressed is also a little awkward. The dinette is cramped which is uncomfortable for a fella as large as me. We do have a bar and ice maker which we barely use. Without these, the dining area could be much larger. The driving area takes about 15 square feet away from our living area. The kitchen area leaves room for only one cook and there is no dishwasher. It is, however, remarkably efficient when you get accustomed to it. There is no comfortable office workspace, and it is a little awkward typing this. It is difficult to find a place to put your shoes and jackets. We do not have laundry facilities.

This is an older unit which is not designed for long term living. It is, however. not intolerable given outdoor living space, and serves to show how little our needs can be. There was a time when many mobile home were not much larger.

The advantages? There is not much area to clean. There is not much space to heat or cool. We use less than 30 gallons of water per day which is only about a cubic meter per week. Laundry may increase that to 40 or 45 gallons. Our electric and fuel use is very small. Although we have 2 furnaces and 2 air conditioners, neither have been turned on since we moved in. .

Size matters in a bedroom

Our bedroom

This motor home has a comfortable double bed. Although we have, for years, been accustomed to a queen size bed, we adapted with no problem at all. So why do we want larger?

The kitchen counter has a built in food processor drive which accommodates several kitchen appliances and saves lot of storage space. This seems like a better option than more cupboard space.

The last couple moves we made showed that we had kitchen stuff we had not used in at least a year. There were still empty spaces in the cupboards. This was just a typical 10 x 10 kitchen but I am sure we could have done with half the cupboards. Counter space always seemed to be at a premium but part of that was because we had a lot of unnecessary stuff parked there.

We are definitely limited, when it comes to indoor entertainment, or overnight guests, but we have found ways to cope. Winter, of course, would make things much more difficult, even if the RV was built for cold weather.

All this has convinced me, that a comfortable home for 2 people, could be designed in about 500 sq. ft.. The 1000 sq. ft. home we are building may seem palatial by the time we move in.

What is the purpose of this little exercise? I think it shows that most of us could do with much less space than we suppose.

Less space means less environmental impact. It also means less initial cost, less maintenance, and less money spent for heating and cooling.

So why are we building a house more than twice that size? A difficult question. Particularly as I am a huge advocate of small.

size matters when you sell
i am real estate photographer / Foter.com / CC BY

We do require reasonable ease and value in resale. We are quite old, and things could change rapidly for us. I don’t believe the market, in our area, is quite ready for a 500 sq. ft. house. We require a second bedroom for a handicapped daughter who spends about 4 nights with us every couple weeks. We occasionally have more overnight guests, so have included extra multiple use space. I do need a comfortable office and computer station. Because of frequent guests and our age we believe two full baths are necessary.

These may be fairly valid arguments, but they do not prevent me from feeling just a bit guilty, for using more resources than we might need.

We did plan for an open concept plan for our kitchen, dining, living and office areas. This allows for some adjustment of the spaces as the need arises. We also planned for the house to be easily expandable, if the need should arise for future owners. The house will have no basement. Expansion that way is not an easy option.

I do ease my guilt, and my wallet, by purchasing used material where possible, and by building an efficient house.

I have no guilt at all about our vehicles, another area where size matters. We live in a rural area, and at least one vehicle is an absolute necessity. We drive a compact car in a five door, or hatchback, configuration. It gives us as much room for cargo as many large cars. Ease of parking, small turning radius, low initial cost, and of course excellent fuel mileage, make me a real fan of small cars. Comfort may suffer some, but not significantly. I feel I gain some prestige in showing my concern for the environment.

car size matters with a family
Mikey G Ottawa / Family Photos / CC BY-NC-ND

Compact cars are probably not an option for families with children, Mini vans are a good choice in this case.

Some will argue a safety difference. In my opinion a large car may not be maintained as well, because of cost. You are also carrying a much larger load of a very flammable fuel. Agility and stopping distances may be reduced with a large heavy car. Survivability in a small car may not be as good when in a collision with a larger vehicle. However, doesn’t that make the large car the killer?

size matters
mrpattersonsir / Foter.com / CC BY

Of course, you can own a big car and still have no more impact on the environment than me. You just have to drive less at sensible speeds. Considering the cost, you likely will.

We also own a small truck (a Ford Ranger,) needed for construction, and as backup. Fuel efficiency is reasonable but not exceptional. We avoid using it if we can.

I have been told that size matters in other fields of endeavor. I think they were talking about my waist size. It certainly reduces my agility and costs a lot to maintain.

Nine ways to make your home more energy efficient. 

Energy efficient building material

Impact of cars on the environment

Share this:
Share this page via Email Share this page via Stumble Upon Share this page via Digg this Share this page via Facebook Share this page via Twitter

Insulation, air barriers and moisture barriers

Insulation in your house is like your winter coat.

Insulation against winter

Bundled warmly

Insulation is a blanket around the house that slows the loss of heat to the outdoors. Alternately, it slows the penetration of heat from the outdoors to your living space. It is easy to see how insulation adds to your indoor comfort, and reduces the energy cost to heat or cool your home.

Your winter coat is not very effective if the wind blows through it. It needs a layer of wind resistant material to be effective. The insulation in your house is similar. It is not very effective if air is allowed to freely circulate in and out of the house. The importance of sealing your home against air infiltration can not be over emphasized, if you are concerned with comfort and energy costs.

A coat or any clothing is not very effective against the cold if it becomes wet. The same is true for insulation. As well as reducing the effectiveness of the insulation, moisture encourages the growth of mold and rot within wall and attic cavities. Once moisture has entered the wall cavity it is reluctant to leave, so it is important that even tiny holes in the moisture barrier be sealed.

Do you remember your science from school? In my case I can barely remember school, it was so long ago. Anyway, we know that heat always moves towards cold (or the absence of heat), and that there will be a greater (faster) transfer of energy when the temperature differential is higher. If there is a science teacher out there, please correct me, if I have not explained this properly. The other pertinent fact is that warmer air rises. This means that the warmest air in your house is at the ceiling, and that this is where the greatest heat transfer can occur. In cooling season, the attic space of your house is going to be warmer than the outside ambient temperatures, no matter how effective the ventilation.

It follows that, added insulation in your attic will effect the largest energy savings.

Insulation for cooling

Poor insulation makes a
hot house in summer

It is also the easiest and least expensive area to increase insulation. There are no doors, and usually no windows, to reduce the overall effectiveness of the insulation. There is a lot of space to add insulation, with the possible exception of the area near the eaves of a gable roof. The use of rafter trusses with heels can alleviate this problem.

It is difficult to get an overall high insulation value in the walls because of windows and doors. No matter how much you spend on windows, you are not going to get an R value much above 4 with 3 being about the norm. Doors are not much better, and need constant maintenance to prevent air leaks. Windows and doors will probably make up from 10% to 20% of your wall area, and in some designs much more. Windows can be an attractive design feature, but can be costly in more ways than one.

There are several types of insulation available.

Fiberglass or mineral wool insulation is commonly available as batts. They are used in wall cavities for ease of installation, and because they are not subject to settling. Each type has about the same insulating value at just over R3 per inch. In other words, A 2 x 4 wall can be insulated to about R12 using this method. A 2 x 6 wall will be about R20. Batts are also often used in ceilings as well, but in my opinion loose fill insulation is the more effective for this application, with less likelihood of gaps. If it is still available in your area, do not use the type that has a kraft paper facing. It only serves to reduce fire resistance and hide gaps that may occur.

Loose fill insulation is either of fiberglass, rock wool or cellulose. Vermiculite was once widely used, but is not popular today, because of possible asbestos contamination. Loose fill insulation is easily installed in open attics by blowing it in. Insulation suppliers will usually supply the equipment for this at a low rental fee, or possibly even for free. Contractors specializing in this type of insulation, and with truck mounted blowers can be hired, if you do  not want to get itchy. Truss members can add difficulty, but are not a serious complication. Application may not be possible in some types of roof. Fiberglass has an an R value of about 2.2 per inch, while rock wool and cellulose are at about 3.1. Cellulose may have the advantage of providing some air barrier qualities. Cellulose insulation is a environmentally friendly product in that it is usually made from recycled newspaper that has been treated with a fire retardant and rodent and insect repellents.

Foamed in place, or spray applied insulation comes in three types, wet spray cellulose, open cell polyurethane, and closed cell polyurethane. R values per inch are respectively 3 to 3.7, 3.6 and 5.5 to 6. The polyurethanes can act as air barriers, and the closed cell type is also a moisture retarder. These are not a do it yourself application, and can be more costly. Polyurethane foam insulation is excellent for providing extra insulation in narrow cavities. They are effective for difficult to insulate areas such rim joists. Available in aerosol cans and formulated for specific uses, foam insulation is excellent for sealing around windows, doors, and other wall perforations.

The more common type of rigid board insulation is polystyrene (often called Styrofoam which is actually a brand name). Other less common types are rigid fiberglass, or rigid mineral fiber insulation. Polyisocyanurate (WHEW, say you can pronounce that and be honest) is a foil faced board. Expanded polystyrene has an R rating of 3.6 to 4.4 per inch while the higher density extruded type is 4.5 to 5. The polyiso sheet is R10.8 for a 1.5 inch thick sheet or R7.2 for 1 inch.

Board insulation can be used as sheathing, and under siding on walls. It is effective at breaking thermal bridges, occurring in house framing with cavity insulation. Self adhesive aerogel insulation strips can be applied to the framing under the drywall to reduce thermal bridging, as well. I am not sure how easy this is to find, as it is a relatively new product. A 2 x 6 stud has an R value of about 7 which is not too terrible. Framing will have to be braced, if using rigid insulation for sheathing. It does not provide the same protection against racking, as plywood or OSB. All insulation must be carefully installed to prevent gaps or compression.

For an air barrier on the exterior walls, a house wrap is applied under the siding. This is material that will allow moisture to escape outward, but prevent air and moisture from penetrating inward. It has replaced tar paper for this application, and is required by code in many jurisdictions. I cannot attest to it’s effectiveness, but demonstrations I have seen are pretty convincing. It must be meticulously sealed with special tape, and caulking at all joints and penetrations. My thinking is that the fasteners used should be somehow sealed over, as well, with tape or caulking, but how would you do that when you apply siding. I would appreciate some input on this. Always lap an upper application over the lower one.

To protect the insulation, a moisture barrier must be applied on the interior side,and also sealed well at joints, openings and penetrations.

It also acts as a barrier against air infiltration. A 6 mil poly sheet is required by most codes. A mil is a unit of length equal to one thousandth (10-3) of an inch (0.0254 millimeter).

Pay special attention to sealing electrical outlet boxes and plumbing penetrations. Electrical penetrations are a serious source of air infiltration. Don’t forget to caulk where wires go through wall plates. Plumbing penetrations occur in areas where humidity is higher, and as a result can be a serious source of moisture penetration. Keep all plumbing to interior walls if possible. Even then sealing is important to prevent condensation from forming on cold water pipes, and creating a pleasant environment for mold growth. Don’t forget the ceiling penetrations for plumbing vents.

I am not very concerned with fastener penetration in the interior. Primer sealer and paint over drywall, provide an extra layer of protection against moisture.

Careful consideration to insulation, air barriers and moisture barrier will pay excellent dividends in comfort and energy savings.

Share this:
Share this page via Email Share this page via Stumble Upon Share this page via Digg this Share this page via Facebook Share this page via Twitter