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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.

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Controlling Humidity in your House

Controlling humidity in your house is important for several reasons.  Comfort is one reason, but preventing rot and mold is likely more critical.

A pretty picture but does not have much to do with controlling humidity
Ian Sane / Foter.com / CC BY

In cooler climates moisture must not be allowed to pass through the walls from the inside to the framing and insulation. Humid air will condense in the wall space and create conditions for mold and rot. In extreme cases, insulation can become saturated, or even frozen into a solid block.

The usual solution is to provide a moisture proof barrier under the interior finishing board. This is usually 6 mil polyethylene. Extra care must be taken to seal against all possible leaks. Electrical and plumbing penetrations are common problem areas as well as laps in the poly.

The Icy Explosion
Stuck in Customs / Foter.com / CC BY-NC-SA

Moisture escaping into the attic can form frost on the underside of the roof. When the weather warms this will melt and can saturate insulation and stain interiors. Good attic ventilation can help to clear moist air that may escape into the space but the poly barrier is the best solution.

Moisture can also condense on inside walls and create an environment for mold. This often happens behind furniture on north walls. Areas with inadequate insulation also create a problem. Forced air heat often does not reach into closets and behind obstructions, hindering drying. Under floor radiant heating is better in this regard. Diagrams of simple radiant systems can be found here.

Too little indoor humidity is not a huge problem but you may be more comfortable if it is maintained at 50 to 60 percent. Older houses with substantial air leakage can have a very dry interior environment in cold weather and a humidifier can add comfort. Too dry air can cause static electricity and dry throats.

controlling humidity can prevent undue window frost
Pretty but can be a problemmonteregina / Foter.com / CC BY-NC-SA

Modern houses are normally well sealed and the opposite often occurs. Moisture added from bathrooms, cooking, laundry and even occupant respiration can raise humidity. Attached garages may add humidity from wet cars or snow and ice melting from car undersides. Un-vented gas cook stoves add considerable humidity as a by-product of combustion. Too damp an environment can cause mold growth and windows may frost up in cold weather. Damage can occur when this frost melts. I have even seen door locks freeze solid and become inoperable.

In cold drier climates the best solution is ventilating with outside air. A heat recovery ventilator keeps heat loss to a minimum. This is the method I use in my house. It has the added advantage of replacing stale air with fresh and reducing odors. So far it has been easy to maintain humidity to between 50 and 55 %.

Many contractors will install complicated ventilating systems with many inlets and outlets. I do not think this is necessary and could be very difficult to balance. One or two well placed inlets and one or two outlets should be adequate for most houses. You should also install bathroom exhausts and a kitchen range hood that exhausts to the outside. You may need a separate make up air inlet for these. It is a good idea to wire the bath exhausts to turn on with the light. People will often forget to turn fans on when needed.

You won't need this large a fan for controlling humidity
Foter.com / CC BY-SA

Ventilators are usually controlled by a humidistat. You may at times want to control it manually to provide fresh air.

You may need a de-humidifier in humid climates or in especially damp basements. Air conditioners normally reduce indoor humidity in hot climates. Humidity makes hot weather much more uncomfortable. The ability of your body to cool itself by sweating is impaired by high humidity.

Most ventilators available today are probably a little larger than is needed for a smaller house. A smaller unit run more or less continuously may be a better answer.  The one in my house is quite large but does not create any real problems except for a slight draft when it is running. Not much of a problem as the moving air is not cold.

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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.

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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.

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Walls

 There are several choices, of construction methods and material you can use, when you build the walls for your home.

Once the foundation is in and the floor is on, the next step is the walls. Despite the lesson of the three little pigs, we still build our homes from straw or sticks, with the most common in North America being the wood frame building. I will deal with this type more extensively, because it is also where most of my experience lies.

Another less conventional style of wall construction is the insulating concrete form filled with reinforced concrete. This produces a strong, energy efficient and quiet building envelope. Often built from the footing to the roof, this method does not require a lot of special skills, and is quite fast. Interior and exterior finishing is not much different from wood frame. The walls are nearly a foot thick, so doors and windows will have to be modified, or purchased specifically, for this type of wall. Probably a little more expensive than other methods, this can still be an excellent choice for cold climates, and likely for hot locations as well. An added advantage is that the concrete can be poured in cold weather.

My experience is limited on this type of construction, as I have only built one commercial building and one basement using it. Both were reasonably uncomplicated, and went very well, considering my lack of firsthand knowledge.

Conventional poured concrete walls are a possible choice for moderate climates, but should be reinforced, if there is any chance of earthquakes.

SIP (Structural Insulated Panel) is another intriguing method for hot or cold climates. Basically a sandwich of various exterior and interior sheathing, bonded to a polystyrene core. They can be of various thicknesses, and can be used for foundations and roofs as well. I will have to depend on links to other sites here, as I have little knowledge and have only seen the method used in a few instances.

Steel frame with metal cladding is not very common in residential construction. Although strong, it has the bad habit of collapsing quickly in a fire.

Wall layersOther methods include various types of masonry wall, straw bale construction, rammed earth walls and many location specific methods using easily available material. Climate and tradition are two of the common deciding factors.

The common exterior wood frame wall can have a few variations as well. The structural framing is usually 2 x 6 or 2 x 8 spaced on 16 inch centers, in cold or hot climates, to allow for more insulation. In more moderate climates a 2 X 4 wall is adequate. A wall with staggered 2 x 4 studs can provide a thicker wall for insulation, while eliminating some thermal bridging.

Exterior cladding is usually a sandwich starting with 4 ft x 8 ft sheet goods of OSB (Oriented Strand Board), plywood or a fire resistant material such as gypsum board. Next would be well sealed layer of house wrap which is designed to allow air and moisture penetration outwards, but not towards the inside. There may also be a layer of rigid insulation over, between, or replacing other layers.

The final or cosmetic layer is widely varied. Commonest today is vinyl siding, because it is attractive, low maintenance, easy to apply and very inexpensive. Although given an R rating I don’t feel it has any insulating value, as it doesn’t provide any real air barrier.

Conventional cement based stucco is still quite common. Very cheap material wise, it takes considerable skill to apply, and is rarely a do it yourself project, although I have done it with moderate success. It can have a great range of textures and colors.

A newer innovation is acrylic stucco. Although not so variable as to texture, it can be used to add a great deal of detail to an exterior. Often applied over a layer of foam board, it provides an extra level of insulation. Detail is added by building up areas with foam board. It can be very attractive.

Natural wood siding is not as popular as it once was, probably because of increasing cost and maintenance issues.

Aluminum siding, steel, various types of composition siding board and brick or stone veneers may also be used. Artificial stone or brick facings are available. Two or more types of exterior treatments may be used together.

concrete wlls

A concret walled building

If you are building in a high rainfall area such as coastal British Columbia, there are some other considerarions. With some combinations of siding, insulation, etc. a rainscreen may be mandatory or advisable. I am from the prairie and am not familiar with this, so will have to rely on links to sites that seem knowledgable. If you think this may apply to you, please do your research.

Insulation is placed between the studs. Batt type is the most common, with the insulating material most often fiberglass, although other material may be used. Foamed in place insulation of polyurethane or other formulations may be used. Although providing higher R values and less gaps, it is somewhat more expensive. Loose fill insulation is often used in ceilings, but seldom in walls, as it may compact and leave a gap at the top. In Cold climates at least, a polyethylene film of at least 6 mil thickness, should be placed on the inside wall over the insulation and well sealed. With foamed in place insulation this might not be necessary. Without a vapor barrier moisture could penetrate the wall cavity and condense, or even form an ice layer against the outside sheathing. If moisture penetrates into the attic cavity, it can cause frost to form against the underside of the roof, which will melt in warmer weather. This can reduce the effectiveness of the insulation, cause rot, promote mold growth and even cause staining of ceilings.

I am not sure what should be done in hot and humid climates, so if any reader has experience or knowledge, please comment.

Interior walls of course, require no insulation, unless desired for soundproofing. Framing of inside walls are usually 2 x 4 wood, but can be other sizes to allow for plumbing, heating or ventilating runs. They may also be of finger jointed wood or steel. Drywall is applied directly to both sides.

Older homes often had interior finishes of plaster or wood, but modern homes are almost exclusively done with drywall (gypsum board,) with joints taped and “mudded”, after which a primer\sealer is applied, and followed by paint, texture or other decorative material.

Drywall slows the spread of fire, and should cover all structural wood, without any gaps for fire to travel through. Door and window openings being the exception.

The subject covered here is too large for a single post, so I have only covered the basics, and will have to rely on links to other sites, if you want more detailed information on specific items.

There you have it, I have actually admitted that I need some help. Twice!!!.

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