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February, 2011

Home remodeling for energy efficiency: prepare for rising heating costs

A complete gut job will result in a more beautiful and efficient home…Eventually!

If you’re considering embarking on home remodeling for energy efficiency, think “energy savings” as a strategy. Energy efficiency perhaps isn’t the most interesting aspect of a home remodel, but it is a crucial issue.   

Let me make an analogy to a car: Many car owners want to do the fun maintenance to their car, like installing a new set of shiny tire rims or a new stereo system. But most often, their money would be better spent on having their timing belt changed and a new water pump put in.  These seemingly mundane maintenances are what keep your car on the road; without their proper function, you have no transportation.

When maintaining your home, think “function first, aesthetics second.” That is certainly not to say that some interesting architectural changes can’t happen in the remodel; some functional changes are connected with aesthetics and energy efficiency. Real-estate appraisal is gradually moving towards valuing homes in energy efficiency. This sort of home-valuing is a bit behind the times, but is slowly moving towards estimating a home’s worth not just by square-footage and number of bathrooms.

Most all scholars and analysts agree that we are now past Peak Oil and that fuel prices will exponentially rise. As we continue to turn past the apex of Peak Oil and start running into the next phases of oil depletion, many of the energy sources that we rely on now, like electricity and natural gas, will become more expensive. The current system of harvesting and refinement of energy sources relies on cheap oil.  Everything from the manufacturing of new oil wells and electrical plants, the transportation of energy, and the installation of a heating system into the home all rely on oil. This point made, lets look at your home. How we can tighten down on home fuel consumption and save you money?

Seal up cracks in barnboard

When remodeling with a focus on energy-efficiency, first look for leaks. Air infiltration is one of the primary areas of concern when trying to achieve tighter efficiency in the home.  Windows, doors, venting, and crawl spaces, are the easier areas that should be targeted. A cold, windy day is a good time to look for air leaks. Simply put your hand up to doors and windows- if you feel a draft, you have found a problem.  

When looking for replacements to your old doors, choose quality, modern exterior doors that come with triple locks (locks on the top, middle, and bottom of door). These locks make a huge improvement on getting the door gaskets to seal completely. Old wooden doors are tall and not very thick; it is common that this type of door will bow end to end along the locking side. The only way to take the bow out of the door is to pull on top, middle, and bottom, allowing the door to fully seat against the gaskets. If you have an old, architecturally elegant door that you just can’t part with, installing a storm door over the old door will help create an air space and should reduce air infiltration. 

A modern, double-hung window installed to meet historic district regulation may be expensive, but will be a huge energy improvement in the long run.
New thermal pane 6×6-
a custom-built historic model

Replacing old windows or installing them in new locations can result in both energy and aesthetic improvement. Properly positioned windows allow natural light into the home and can help ventilate the home without the use of electric fans or air conditioning, saving you money. Windows also can allow for solar gain to occur- a source of free heat. Replacing old windows can result in huge energy savings. Old, single pane windows have very little insulative value, whereas modern glazings create resistance to air temperature change by having an airspace between panes and light filters. Most old windows have no insulation around their perimeters, allowing for air leakage.  Modern windows typically have better seals and gaskets, are foamed into their hole, and are installed to be water-tight. 

Framing in new windows
Replacing windows can offer a perfect time to rearrange how your home looks. You do not need plug the same window holes with the same window types. A fresh new look can be achieved with new strategies as to passive solar gain, ventilation and window typology (casement, awning, double hung, sliding).  A rearranged window remodel plan can result in new views to the outside.   

Adding insulation to your home is another way to improve energy-efficiency. In old homes, installing insulation can be tricky; each old home has its own set of battles in retrofitting new insulation. Roofs must be insulated properly as heat rises and will exit here, however, old homes typically have little to no roof insulation. Before the development of modern insulation, old buildings were designed to have an uninsulated attic that created an airspace between lower living spaces and the outside cold. The attic was not meant as a living space- it was too hot in the summer and too cold in the winter. Historically, the attic was used as storage space, however, many attics today used as bedrooms. 

Retrofit  insulated attic

In many old attics, there is often not enough head room for lowering ceilings and add the appropriate thickness of fiberglass batten insulation and required vent space. Vent space is critical because it prevents damaging condensation from occurring, which can destroy interior materials. In Bozeman, Montana, the modern energy codes require vaulted ceilings to meet R-38 and flat or truss ceilings to meet R-50. For these reasons, uninsulated attics are usually retrofitted with modern rigid insulation or sprayed foam, the latter of which has better performance, but is more costly. (Read a past blog entry about insulation here.)

Old roof off
New third floor and properly insulated roof
Bye-bye dark, cold attic
Old attic became a new 3rd floor

In some cases, it is better to completely remove the existing, uninsulated roof and reconfigure it to create a usable space. By remodeling the attic into an additional floor, you can achieve interesting, high-up views as well as appropriate insulation and venting.  I remodeled a home on Walnut Street in Portland, Maine (see write up here) where the existing attic and roof were completely removed. A new shed roof and floor system were built, creating a beautiful and spacious third floor. What had been a dismal, cold attic with no views became a penthouse with decks on each end and amazing views of Back Bay.

Insulating walls is another important home energy improvement. There are many ways of insulating walls, which are usually determined by the home’s existing wall type, such as 2″x4″ or 2″x6″. When assessing a home’s remodeling and insulation needs, I ask the questions like, “Is your exterior siding in need of replacement?” “Do you want new interior wall surfaces (drywall, plaster) because the old walls are rotted out or falling down?” There are different strategies depending on your home’s condition. Assuming that the exterior walls are already insulated, one strategy to increase your wall insulation performance is to add furring strips and rigid foam to the interior walls. This works well with 70’s style homes that were framed with 2×4’s and insulated with R-13 fiberglass batten insulation.  

‘K’ braces … blown in cellulose nightmare

Very old homes have no insulation inside the wall cavities or have blown-in cellulose insulation. Blown-in cellulose was typically installed by drilling 2″ holes into the exterior siding, then pumping the feathery, down-like material into holes at the top of each stud bay. Usually one can find evidence of this if there are bunged holes in the siding. Filling an old wall with cellulose only gives a R-value of about 13, which is not sufficient insulation. As condensation forms inside the stud space, the cellulose becomes damp, decreasing its insulatative value.  Also note the image here, ‘K’ braces in the corners… blown in cellulose will not fill these voids.  Only from the inside can one get to these places to insulate properly.

An old home’s insulation level can usually be estimated by the plaster and lathe condition, which was the interior wall surfacing before modern insulation and drywall. If the lath nails are rotted out (see this blog) and the interior plaster, usually  new windows, plumbing and electrical infrastructure are also needed. The interior plaster and lathe should be removed, then new studs should be furred out to meet the modern 2×6 wall. I remodeled a home on Gray Street in Portland, Maine where the walls are remodeled as such (read about that here). This is a expensive solution, but is really the best solution because all problems can be fixed at the same time. It makes no sense financially to remodel a home over and over again.  

Insulating crawl spaces and basements can offer energy savings. Most old buildings have uninsulated basements; the idea was that used heating system kept the underside of the floor system warm. Some argue and uninsulated basement spaces are acceptable because the earth’s temperature at that depth is warmish and that open walls and flooring makes the plumbing more accessible. However, this thought process was from the days of cheap oil. The earth is a giant heat sink with endless mass. By not insulation your basement or crawlspace, your are essentially attempting heat not only your home, but also the earth. To promote energy savings in your home, the floor system above the basement and should be insulated. If hot water plumbing is hanging down into this space, it also should be insulated. 

Foamed-over brick foundation

Insulating the basement foundation with either rigid foam or blown foam is important to prevent external ground temperature from bleeding inwards.  Keeping this space as warm as possible makes sense, but not by heating it with expensive fuel; allow the insulation to store what heat there is. If your basement has old single pane windows, you can cover them during the winter months with rigid foam board and  caulk any obvious drafty cracks.  

The warmth and beauty of stained concrete radiant

In homes with a decent southern exposure, it is possible to add a radiant floor to increase mass of the building and to promote passive solar heating. This can promote huge savings in heating costs. It is important that a designer with experience in passive-solar design develop the system are floor plan and layout to the south, as well as associated windows on that exposure. It is possible in certain situations to add an external addition on the south side of the building that has a slab on grade with radiant tubing. In some homes, where ceilings are taller than 8 feet, it is possible to install a 1.5″ slab with tubing over the existing sub-floor. This must be evaluated by a designer or builder to ensure that the floor system is sturdy enough and that it doesn’t cause elevation problems in between rooms, door heights and swings, etc.

If you are considering home remodeling for energy efficiency,  please contact Greenovision with any questions you may have. We have a lot of experience in many different areas of home remodeling and we would love to help you out. 

Greenovision Awnings: Create a Welcoming Entryway with Natural Light

Fresnel prismatic effect  of polycarbonate Greenovision Awning

It is important that a home’s entryways have roofs above the doorways, protecting the doors against weather. Snow, rain, sleet, hail and extensive UV radiation all have damaging effects on a home. Entryway roofs protect the threshold into the home from damaging moisture and creates a safe, snow and ice-free entry and exit. Most homes have ‘hard roofs’ over their entryways. By ‘hard roof,’ I am referring to a non-transparent, typical layered roof system, such as sub sheathing over rafters, flashing, tar-paper, then asphalt or metal roofing. These type roofing materials are expensive due to the labor of multiple applications of materials and in the end, create a dark and rather gloomy experience of entering into a home. Welcoming guests into the home is much more comfortable when the visitor and host can see one another well. Being able to see well breaks down feelings of uncertainty and makes for a more cheerful, less awkward welcoming.   

In order to create a more friendly and welcoming entry, it is beneficial to increase natural light levels. However, it is still important to break down UV light and to protect the threshold and doorway from the elements. I have found that by designing and building awnings made with polycarbonate panels (greenhouse glazing), I can create a well-lit entry with the benefits of protection from weather and sunlight. The type of polycarbonate I use has a UV filter; it protects and preserves finished wood, increasing the lifespan of doors and other exterior materials. 

 In snow country, polycarbonate roofs, if given a minimum slope of 3/12, will usually slick off snow as soon as it falls.  If snow does collect, it slides off the awning when the temperature is above freezing. Having a snow-free roof keeps the light transmittance up and the snow load down. Reduced snow loading allows the roof to be constructed with fewer rafters, giving a simple, modern, less-cluttered appearance.   

What if your entryway is too bright? Polycarbonate roof panels are an excellent sunlight filter. There are different filter ratios designed into polycarbonate, which can be used to reduce sunlight levels. Polycarbonate has some interesting qualities that can also be used to create various visual effects. The panels are made of square cells that when lit, give off prismatic effects that broadcast over its surfaces.  At night, lights can be aimed at the awning, causing the polycarbonate to look like a luminaire. This effect makes a home’s entryway stand out and come alive at night when guests are arriving.  
 
Polycarbonate panels are sold in four-foot widths and can be cut at any length. No mid-span rafters are needed if the panels are fastened around the perimeter correctly. I usually custom-build the frames with welded metal for longevity. The metal frame will last through multiple polycarbonate re-roofs, but the polycarbonate panels will need to be replaced, as does all roofing. Polycarbonate is given a typical 10 yr warranty, but in my experience, it lasts much longer. Most of the time, I use a 16 mm triple celled panel, which has very good strength to weight ratio. Polycarbonate is flexible, unlike glass, which enables it to take hits from falling objects like hail, branches, and ice falling from roofs above.  


Polycarbonate awnings can also be placed over large windows to protect them from Montana’s fierce hail storms. In Spring 2010, Bozeman, Montana was hit by a hailstorm that shot golf-ball sized hail. Most all Bozeman homeowners needed to replace at least one broken window. A polycarbonate awning placed over a window prevents this hail damage. A polycarbonate awning is also helpful during Montana’s hot summer. Although polycarbonate allows light to penetrate to the window, it breaks down heat and strong sunlight rays. This helps the home stay interior stay both cooler and naturally-lit.   

The shadow line is of a filtered light, not completely dark

The proper design of each polycarbonate awning is crucial. Every home has its own unique architectural style, color schemes, layout issues, and structural details. It is important that each awning be designed to take these variables into account so that the results are aesthetic, efficient, strong, and add to the entryway a sense of welcoming.

I really enjoy building these unique polycarbonate awnings and have built them in many different sizes, shapes, and colors. A Greenovision Awning can be a beautiful and functional improvement to your home. Please check out the awnings section of the Greenovision website for more examples of previously built awnings. 

A Small Home That Grows When You Do

The following images are Greenovision computer generated models

Small home design

Why build a small home?  There are many reasons.  In my past blog, I discussed the construction cost reasons; see that blog here. Just keep in mind that the “American Dream” of owning a home should not indenture you for life to a bank.

Plan to build small with the option growing as your needs and budget grows. Plan to save materials before the home is built. Plan on using quality recycled materials by designing them into the home and saving them before construction begins. Building an affordable, functional, and beautiful home is all dependent on design.

The home I am designing for myself employs these principles. The “tiny home movement” is valid in that it teaches people to live simpler and in smaller spaces with less clutter, however, it does have its short comings.  I have friends that started with tiny homes (10′ x 9′) and it worked for a while, but guess what?  When it came time to have someone over there was no room to ‘entertain’ them.  These homes were just too small and were not designed to be added on to.  So, they had to start over and build something larger.


This is where I am heading with my small home design- how to build small to get on a site affordably, but how to plan for addition of space as funds and more spaces are needed. The top rendering shows Volume 1 as the main volume, which is two stories.  The other volumes can be added on later. This does take some planing so that wiring and conduits won’t have to be rerouted.  Also, with good planing and design, windows come out and an interior door goes into its hole making passage to the new addition.  Another area of concern is where the new roof meets the old wall. This can be built into the exterior wall with flashing and ledger so that when it is time to add on, no siding has to be removed.  Some siding looks rather nice as an interior wall, such as a vertical cedar board v-match or ship-lap.

open interior space of living area

 

Loft bedroom and desk

I have come up with several key ingredients to a small home design.  One is, don’t make it too small. Create a main space that gives ample room for a kitchen, a place to eat, and a place to entertain, meaning some nice seating with pleasant outdoor views. Such seating can as act as a place to sleep if a guest stays over if the couch is a ‘fold out’.  Give room for stairs that meet modern codes ( 7.75 inches of rise to 10″ of tread usually).  Have a loft above or a second story where you will sleep and can have a desk and closet space.  Having a second story saves on roofing, insulation, and foundation.

By making this main volume tall, the home is prepared for lower, smaller additions to be easily added on later. Such additions can be another bedroom on the first floor, a mudroom with increased storage, and laundry and counter top space for gardening projects or household tasks that you don’t want to be doing on the kitchen counter.  Also, a main bathroom could be added to another side of the building at a later date or at the beginning.  Which volumes you choose to begin with all depends on your initial start-up budget.  Remember: building too small will make it harder down the road for adding on.

Don’t forget that with good design, built-in shelving and storage can use space that once seemed unusable (under the stairs, etc). Efficient storage space is important in a small home. Many small homes never a plan for enough storage. This simply doesn’t work and the residents often end up storing their stuff outside in the weather, cluttering up their site.

My home shown here starts out with a main volume that is 16′ X 24′  with a second story, or 768 square ft. The additional spaces are a bedroom at 12′ X 13′-6″ (162 sq ft), a mudroom at 8′ X 10′ (80 sq ft), and a bathroom at 8′-6″ x 11′ (94.6 sq ft)  for a total of 337 sq ft more. All of the volumes together gives the plan a total 1105 sq ft. This is a very comfortable-sized home for a couple or small family.

The design of my home will change a bit when I find a specific building site.  This home is designed for passive solar gain; there is a concrete slab floor to the south.  Depending on the site, the concrete can either be slab on grade or a slab over a typical joisted floor system. I will configure some of the building to have a full basement for utility and washer/dryer if the site is conducive to this.


Cheaper land often has ledges, which makes a basement expensive. In this case, there will have to be an additional volume built for utility and laundry.  Some of the foundation can be on piers, some can be crawlspace foundation, but those issues depend on the site.

I have posted this project under a new section on my website, www.Greenovision.com, that is dedicated to small home design. Check it out here. To see a similar small home that I designed and built in Maine, check out Liberty House.

The computer images and drawings shown on this blog were created by Mark Pelletier and are property of Greenovision, LLC. Beware of the copyright monster!