Reposted from i.e., the Center for Energy and Environment's Innovation Exchange blog -- http://mncee.org/Innovation-Exchange/ie/
Typically, an energy auditor knows very little about the house she is visiting until she actually arrives at the house. In a previous i.e. post, we discussed how commercially available apps can enhance your efforts during the house visit. In this post, we’ll describe how you can gather important information about the house prior to the visit while sitting at your desk. Thanks to the Internet, you could begin filling out the audit form before stepping into your car and even perform a visual inspection of the exterior of the house. This post will discuss a number of available tools and describe other useful analyses that can help prepare and expedite your house visit.
When you get the address of the house that you will be visiting, Google Maps is probably the first place to turn. The site provides both directions to the address and a satellite view to give you an idea of the site plan.
Google Maps has a tool that allows you to measure the area of the plan view and a distance measuring tool to measure the length of the sides of the house, all using the satellite view. When available, Street View provides a good shot of the front and sometimes the sides of the house.
Bing Maps’ bird’s eye view is another great tool to allow you to perform a virtual exterior inspection of the house. Aerial photographs from a low flying aircraft give you oblique, 45° angle views of the house from the four cardinal directions. Like Google Maps, it also will give you directions to the address.
In some areas, Bing Maps offers a Streetside View. Recently, Google Maps also has also begun providing a 45° angle view.
From this exterior inspection you now know the style of the house, type of roof, an idea of the type of siding, house orientation, and any features of the yard such as shading, exposure, swimming pools. You also have envelope details such as bay windows, overhangs, and other features that can affect the air tightness of a home. With this information and an estimate of house dimensions, you can already begin an initial floor plan.
In Minneapolis, you are also able to access city assessor data online. By simply inputting the address of the house, we can get building information and building permit history. Building information includes data such as cost of the house, age of the house, area of each floor, area of finished basement, and number of bedrooms and bathrooms.
For each address you can also learn which building permits were pulled on the house and when. This can give you information about the heating system as well as any envelope improvements that may have been done, as long as a permit has been pulled. The real estate website zillow.com can also provide building information if you can’t access the city assessor data. Zillow also provides Bing Maps’ Bird’s Eye Views and Google Maps Streetview for each house.
In many ways, the accumulated data could be used to perform a simple energy model of the house. You can use online tools like Home Energy Saver or EnergySavvy to create an initial report on the house with recommendations and savings estimates provided by the model.
Nielsen Claritas provides a free online tool that lets you investigate the market segment characteristics of the house’s area based on its zipcode.
This could give you some ideas of the types of communication style and messaging you could employ to best persuade the homeowner to take energy efficiency actions. The price of the house might also provide you with some insights on lifestyle types. The ratio of home price to income could probably be assumed to be around two to three.
Through our residential program, we typically have gained access to the past twelve months of the residents’ natural gas and electric utility bill records. We use this data to create a Home Energy Snapshot before performing the audit, and arrive prepared to explain the information to the homeowners. With prior knowledge of their energy use, we can learn if they are high, average, or low energy consumers.
And analysing their monthly utility bill data for the past year can give us insights into their gas and electric heating, cooling, and baseload use.
All of this desk work may take a little effort prior to the actual visit, but should save you time in the field and can also help direct and guide your visit. On a program level, this house screening may help you perform a triage on your houses and allow you to focus on homes with high energy savings potential. It could also improve scheduling by helping you identify appropriate times depending on difficulty and assign auditors based on experience and expertise.
Francis Bacon is often credited as the Father of the Scientific Method and it is this process that is often considered the basis of scientific thought. The method of scientific inquiry can be defined by the following steps:
A level of scientific inquiry could be applied to the overall audit and retrofit process on the set of houses you're inspecting. Depending on your program, questions could be: will using a specifc marketing and communications approach for homeowners in this zip code inspire them to investment in energy efficiency? Do pre-WWII houses of a certain value typically have uninsulated walls? Each house serves as a test of the hypothesis. The “desk jockey” screening we’ve described here could institute a program-wide approach to collect information and develop insights about the entire housing stock and residential community. When you become a research scientist in addition to a building diagnostician, your whole program learns as a result.
Related CEE programs: