then your indoor air quality is suffering. You are also paying too much to heat and cool your home. Vented crawl spaces usually have insulation located in the joist spaces. This insulation gets pulled away from the heated surface by moisture in the space, which opens up air gaps and reduces any insulation value at all. The space usually has high humidity levels promoting mold growth. The heating and cooling vents running in that space usually have minimal insulation allowing for condensation to occur in the ductwork, again impacting indoor air quality and efficiency of the HVAC system.
Instead of a vented crawl space in our mixed humid climate, you should have a conditioned crawl space – like this one. Here is an example of an excellently sealed space.
My community’s wellbeing is our main concern, so give us a call for some great referrals to businesses that you can trust. If you are looking to build your home or business, read this post about how to achieve a healthy building through proper HVAC installation.
Heating water in the average home accounts for up to 15% of a home’s energy use. So what is the best water heater for efficiency? Should you purchase a conventional water heater with a low up front cost or go to a more efficient unit?
Demand (tankless) water heaters circulate water through a large coil that is heated using gas or electricity. There is no storage tank continuously heating water. There is an endless supply of hot water, but there can be limitations on the number of fixtures that can be used at one time.
Heat Pump Water Heaters transfer energy from the surrounding air to the water in the storage tank. They are most effective in warm climates with long cooling seasons. They will cool a room by 1-2 degrees and dehumidify the space.
Solar Water Heating takes heat from the sun to heat water. Solar systems require a conventional water heater as a backup to ensure heated water at night.
So which is the right option for efficiency? The 13 year cost of a minimum efficiency electric storage water heater is $6,800. Most of the costs are in utilities for this option which can be offset with solar PV.
A on-demand gas unit costs more up front, but the 13 year cost is $5,000 with all of the savings being in energy use.
A solar water system with electric backup eliminates most of the electric costs, but the 13 year cost is $7,000 due to high initial costs.
So based on my research the electric heat pump water heater with a 13 year cost of $4,000 is the winner. This is a $2,800 savings over 13 years and the low energy costs can be offset with solar pv.
The profession of architecture is often looked at through the lens of television or magazines – how to make buildings beautiful. However, that is not the true work done by architects. Beauty is a minor part of the equation. Beauty is the part of the design process that can be replaced by purchasing a plan online and giving it to a builder with “a few changes.” Building science is what makes a beautiful building last for years.
A good architect will talk to you first about function over form.
What are your needs? How do you want to use the building? What are the rules that need to be followed, building code, zoning? What are the rules that can be broken? Where will you put your Christmas tree? Do you like to host Super Bowl parties? Do the kids have a dedicated place they can do their homework? How loud is the television downstairs when you are trying to sleep upstairs? Where will you store your stuff? What kind of light will be in that room?
Even better questions can follow a line of building science guided decisions.
How efficient will the house be once you move into it? Will you feel comfortable in all the rooms year-round? How much money will you spend heating and cooling your home? Building science questions are the only questions that have answers that result in money saved. Building science questions almost always address the quality of things that cannot easily be changed once the home is built. Building science questions are almost always the most important decisions that are needed to be made before a builder gives a price to construct the home.
Who sets the building science goals of a project?
Most builders will not be focused on thinking through building science decisions when they are given a set of house plans. Their goal is to build the home in the most efficient way possible according to the plans you gave them. So if they don’t set the building science goals, who does?
Air gaps in ceiling corners
If you purchase a plan online, the designer does not know what site you are building on or the climate you are building in. If you hire an architect that does not discuss building science solutions (insulation types, wall systems, HVAC efficiency, water conservation, ventilation, lighting….) then who will set the standards for your home. Typically the fall back for these solutions are building code, but keep in mind that building code is the worst possible solution allowed by law.
Not all architects consider building science solutions, but a good architect does.
Building sciences require a holistic approach. It is not simply adding more insulation in the walls or attic. Insulation decisions have to be made along with heating and cooling efficiency, ventilation, and window selection in mind. These questions, and more importantly, these answers have to be done holistically or you will create more problems than you solve. Using the wrong insulation in the attic can lead to huge moisture problems. Locating the HVAC ducts in the wrong space will lead to condensation and higher energy bills.
Buildings are complicated, probably the most complicated machine you will ever own. Make building science as important as the countertop selection you are making for your kitchen. Don’t leave out building science during design.
It certainly has gotten cold here. As I write this, it is 17 degrees outside and the high for tomorrow is in the 30s. This sudden change in weather has certainly hit me hard. I hope you are staying warm. Speaking of staying warm, is your house comfortable? Do you have enough of the right kind of attic insulation in the right places?
Over the years I have been in a LOT of attics and most of them do not have the right kind of insulation and certainly not enough of it. Even worse, there is often duct work running in the space on the wrong side of the attic insulation, the cold side, with very little insulation around the ducts. Code says you need R-38 insulation in the attic as a minimum. I would say that is about half what you should have for your attic in our climate if you are using fiberglass insulation or cellulose. Think of it as adding a second blanket to your entire house.
In areas where duct work penetrates the conditioned space at the supply points, there is no insulation. Having the duct work inside the thermal envelope would fix this problem. So if you have the chance, insulation on the underside of the roof sheathing, open cell spray foam, is certainly a better solution than fiberglass or cellulose on the floor of the attic (when duct work is in the space). Spray foam is air tight and when installed in the appropriate places will make your homeboth comfortable and energy-efficient.
Other holes that exist in the insulation envelope can be can lights and eave ventilation that does not have baffles. These holes and air leaks from improper sealing of the thermal envelope all combine to diminish the effectiveness of your installed insulation. Finding ways to stop air leakage and installing the proper amount of attic insulation will help on these cold days.
If you have fiberglass insulation, add more to achieve R-72. If you have cellulose, add more to achieve R-72. However, if you want to get it right insulate with an air tight solution, open cell spray foam is the easiest method to create a home that will be comfortable and energy-efficient for many years.
Air tight is the most critical element of green building design. The easiest way to be air tight in an existing home is using caulk at every gap and crack between building materials. The top and bottom plate of a wall, electrical outlets, doors and windows, all penetrations need to be sealed and air tight. The attic access should be considered as a door and weather stripped and insulated. The rim board (the place where floor joist meet the exterior wall) is always a huge air leak. This can be fixed in an unconditioned crawl or an unfinished basement.
There are many places where air leaks impact comfort and energy-efficiency in the average home. Ducts that are not sealed tight leak out air before it reaches the room it is intended to heat or cool. Double Hung windows have a weak air seal where the two window panes intersect. A finished wood floor will leak air into the crawl space below. The tongue and groove vaulted ceiling will leak air to the outside of the thermal envelope. Air always leaks around recessed can lights. Any penetration in the walls from outside for water lines, electrical panel, or dryer vents are consistently a place for air leaks.
Seal these gaps and cracks with a silicone caulk to stop air leakage before you take any other action. The next step, insulation, can also do the air sealing if you use spray foam.
In every house I visit to do an energy audit, the electrical outlets have been a major source of air infiltration. Sealing these holes up in your thermal envelope will reduce your energy usage and make your home more comfortable.
Yes, I realize these are small areas with small gaps. However, there is very little if any insulation behind the box in the wall. There is almost never any air sealing around the box.
The easiest first step is to add child protection covers to the outlets. This stops some of the air moving through the outlet. The next step is to add insulation strips behind the outlet cover. While they are thin and offer very little R-Value – they are better than nothing.
The final step, seal the box tight to the drywall.
All of these steps should be done in order to maximize the effectiveness of the solution. Sealing and insulating all the outlets in both interior and exterior walls is a critical first step in making your home more energy-efficient. To learn more about making your home energy-efficient, read this post.
Heating water in the average home accounts for up to 15% of a home’s energy use. So what is the best water heater for efficiency? Should you purchase a conventional water heater with a low up front cost or go to a more efficient unit?
So which is the right option for efficiency? The 13 year cost of a minimum efficiency electric storage water heater is $6,800. Most of the costs are in utilities for this option which can be offset with solar PV.
Even better questions can follow a line of 
It certainly has gotten cold here. As I write this, it is 17 degrees outside and the high for tomorrow is in the 30s. This sudden change in weather has certainly hit me hard. I hope you are staying warm. Speaking of staying warm, is your house comfortable? Do you have enough of the right kind of attic insulation in the right places?
Other holes that exist in the insulation envelope can be can lights and eave ventilation that does not have baffles. These holes and air leaks from improper sealing of the thermal envelope all combine to diminish the effectiveness of your installed insulation. Finding ways to stop air leakage and installing the proper amount of attic insulation will help on these cold days.
If you have fiberglass insulation, add more to achieve R-72. If you have cellulose, add more to achieve R-72. However, if you want to get it right insulate with an air tight solution, open cell spray foam is the easiest method to create a home that will be comfortable and energy-efficient for many years.
Air tight is the most critical element of green building design. The easiest way to be air tight in an existing home is using caulk at every gap and crack between building materials. The top and bottom plate of a wall, electrical outlets, doors and windows, all penetrations need to be sealed and air tight. The attic access should be considered as a door and weather stripped and insulated. The rim board (the place where floor joist meet the exterior wall) is always a huge air leak. This can be fixed in an unconditioned crawl or an unfinished basement.
In every house I visit to do an energy audit, the electrical outlets have been a major source of air infiltration. Sealing these holes up in your thermal envelope will reduce your energy usage and make your home more comfortable. 
