Electrify Everything? (part 1/?)

So in utility and policy circles, electrification is all the rage. Grid electricity is getting cleaner (i.e. resulting in lower CO2 emissions), on-site renewables are taking off (sometimes even with storage), and heat pump technologies are getting better. More regional and utility initiatives are encouraging building owners/designers/developers to forego onsite fossil fuels entirely (or at least mostly) to help meet CO2 emission reduction goals. But is electricity really more sustainable than natural gas? Is it cheaper? Which is better, really?

Read more

How to Implement an Efficient Lighting Strategy in a Multifamily Passive House

Walking the aisle of your favorite home improvement store, you’ll notice the wide array of options for very efficient light fixtures. Don’t be fooled – truly efficient lighting design is achieved through thoughtful layout and proper controls.

Hallway lightingA high performance building warrants an efficient lighting strategy. With so many efficient LED fixtures available on the market, individual fixture efficiency is rarely an issue. However, these fixtures are often placed in high concentrations or at a higher wattage than necessary to adequately illuminate a space. The result is high lighting power density (LPD), which is measured by dividing the total light fixture wattage in a room by the square footage of that room. Even with controls such as occupancy or vacancy sensors, high LPDs are especially energy intensive in frequently occupied common areas, e.g., corridors and lobbies of multifamily buildings, impacting the bottom line efficiency of all buildings.

Projects pursuing Passive House certification are impacted by an optimized lighting scheme more so than a code-built building. As the heating and cooling energy used in a Passive House building decreases due to an excellent thermal envelope, the ratio of lighting energy used increases. Reducing lighting energy use can drastically improve the building’s overall primary energy demand. Read more

Tech Notes: Meeting the Accessibility Criteria for Horizontal Exit Doors

Getting out of a building during a smoke or fire event can be traumatic for anyone. But, just imagine how traumatic it can be for a person who uses an assistive device, such as a wheelchair? If proper maneuvering clearance is not provided at doorways, then a person can become trapped.

Building code requirements for accessible means of egress have been developed to ensure that people with disabilities can exit buildings safely in the event of a fire. These requirements, found in chapter 10 of the International Building Code (IBC), establish proper maneuvering clearances at certain doors to safeguard against the potential for entrapment. Horizontal exit doors are an example of such doors.

Horizontal Exit Doors

horizontal exitWe’ve all seen them; in a hospital corridor, at the school cafeteria, or near the elevator lobby in a high-rise apartment building. They are doors that are held open most commonly by magnetic locks, which are connected to the building’s fire alarm system. When the building’s fire alarm is triggered, the magnetic hold-open device releases, and the doors close to contain smoke and flames.

 

The 2015 IBC defines a horizontal exit as:

“An exit component consisting of fire-resistance-rated construction and opening protectives intended to compartmentalize portions of a building thereby creating refuge areas that afford safety from the fire and smoke from the area of fire origin.”

 

Read more

Does Your Exhaust Fan Suck? Part 1

You most likely don’t even think about it when using the bathroom. Flip the switch, hear the exhaust fan, and everything is working as it is intended…right? Far too often, the answer is NO, and it is no fault of the user. Sure, homeowners should take a minute each year to vacuum the inside of the exhaust fan housing, but otherwise, these fans should just work. So why don’t they? Hint…it all depends on how it was sized and installed.

Background

The purpose of exhaust ventilation is to remove contaminants (including moisture) that can compromise health, comfort, and durability. Exhaust fans are amongst the simplest mechanical systems in your home, but decades of experience working in homes has shown us that even the easiest things can get screwed up. Far too often, exhaust fans rated for 50 or 80 cubic feet per minute (cfm) of air removal are actually operating at less than 20 cfm. In theory, the exhaust fan should be installed in a suitable location and then ducted to the outside via the most direct path possible. However, the installation of an exhaust fan can involve up to three trades: an electrician typically installs and wires the unit; an HVAC contractor supplies the ductwork; and, the builder/sider/roofer may install the end cap termination. What could go wrong?

As energy efficiency standards and construction techniques have improved over time, new and retrofitted buildings have become more and more air-tight. If not properly addressed, this air-tightness can lead to moisture issues. Quickly removing moisture generated from showers is a key component of any moisture management strategy. While manufacturers have made significant advancements in the performance, durability, and controls of exhaust fans, these improvements can all be side-stepped by a poor installation.

So how do you correct this issue? Read more

Multifamily Green Building Certification Program Comparison

If you’re designing and constructing multifamily buildings, chances are you’ve run into one of the many green building certification programs. Whether mandated by code, tax credits, your loan, or because you want to improve building performance, the differences between programs can be difficult to understand. One of the most frequent questions we help design teams answer is “which multifamily green building program should we choose?”

To help shed some light on the major green building standards, we’ve outlined some of the most important requirements for multifamily building performance that tend to differentiate the programs the most.

ENERGY STAR

Administered by the U.S. Environmental Protection Agency, ENERGY STAR is a free program that includes envelope, mechanical, and moisture management requirements. There are two pathways to certification – ENERGY STAR Certified Homes and ENERGY STAR Multifamily High-rise – based on the height of the building. In the near future these programs will merge into one Multifamily New Construction standard.

Although it isn’t considered a full green building program (it doesn’t address materials, site or water), ENERGY STAR is included in this comparison because several programs and standards reference it as a base requirement.

Energy Star comparison chart Read more