Paul Fisette of the University of Massachusetts Amherst says that these home improvement jobs can be the perfect opportunity to boost your home’s energy efficiency and lower your heating bills, especially if you own an older home.
“Often a catastrophic event like water dripping from the ceiling can launch home improvement projects into high gear, but there is a lot you can do beyond fixing leaks and replacing worn exterior siding,” says Fisette, head of the department of natural resources conservation and an expert on green building. “A well-designed exterior retrofit will lower energy bills and improve the comfort of your home by eliminating drafts.”
According to Fisette, roof shingles need to be replaced every 20 years, and if your home needs a new roof, it is safe to assume that it also needs new, or at least better, insulation. “Homes built 20 years ago are under-insulated by today’s standards, since fuel was cheap then,” says Fisette. “Builders of that time didn’t devote much attention to insulation and air-tightness. High energy bills, drafty indoor climates and ice dams on the roof are all costly symptoms of these subpar designs.”
For most homes, an energy retrofit of the ceiling is fairly easy. Just climb into the attic, block all air leaks connecting the living space to the attic with foam insulation from a can, and increase the thickness of the insulation on the attic floor. You will need 12 inches of fiberglass or cellulose insulation to deliver the R-38 values recommended for much of the country. A good plan is one that provides a continuous insulation barrier between the attic and the living space below.
The situation gets more difficult in cape style homes and homes with cathedral ceilings, where sloped ceilings mean that areas between roof rafters are sealed by finished surfaces. Shallow roof pitches can also be problematic, since there may not be enough space between the rafter ends and the attic floor to install enough insulation. In these cases, insulation needs to be added after the lower edge of the roof has been removed, exposing areas that were inaccessible from the inside. Insulation products with a high R-value per inch, such as rigid foam, may also be required due to space constraints.
If your siding has also seen better days, replacing it can not only dress up your home, but can also be a way of addressing places where air leaks, holes and lack of insulation reduce your homes energy efficiency.
“At first, this process may seem simple; just strip off the old siding from the walls, replace any failing trim, and put up new siding,” says Fisette. “But this limited vision can lead to lost opportunities to increase the insulation in the walls.”
Fisette says he is constantly surprised by the number of old houses that don’t have enough, or any, insulation in the wall cavities. Many owners of older homes replace or add to the insulation in the attic, where it is fairly easy to reach, but avoid the more complicated enclosed-wall insulation. Filling these cavities with blown-in cellulose, fiberglass and foam when old siding is removed becomes much easier, since the insulation can be placed in the wall cavities through holes in the exposed outer sheathing.This is also the time to repair loose sheathing, replace any rotten wood and patch all gaps, holes and seams with foam insulation from a can. Sealing around window and door openings should also be done at this time.
For maximum energy benefits, Fisette recommends wrapping the exterior walls with rigid foam insulation, which is available in sheets. The rigid foam can be attached to the sheathing with glue or nails, and seams should be taped. Since siding should not be nailed directly to the rigid foam, this process can get a bit tricky, requiring the use of vertical wooden strips attached to the foam sheets to serve as anchors for the siding. This creates an air space between the siding and the insulation. While it may seem like a lot of work, this method will provide a tight, dry and warm structure for many years.
Fisette says that payback times are the most common question posed by homeowners, who wonder whether the cost of extra insulation will transfer into savings. “Payback can be very hard to calculate, since it depends on how much money is spent on improvements and a host of other factors, including climate, existing levels of insulation and fuel costs,” says Fisette. “Calculations on savings for adding insulation to the walls of a standard ranch house predict a five to 10 year payback.”
Paul Fisette | Newswise Science News
Energy hybrid: Battery meets super capacitor
01.12.2016 | Technische Universität Graz
Tailor-Made Membranes for the Environment
30.11.2016 | Forschungszentrum Jülich
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water
In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...
The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
02.12.2016 | Medical Engineering
02.12.2016 | Agricultural and Forestry Science
02.12.2016 | Physics and Astronomy