An AERC rating can help you compare the energy performance of window shades, blinds, shutters, and other window attachments. It applies to a specific certified product, not to every shade that looks similar or uses words such as "cellular," "thermal," or "blackout."
Before buying for energy performance, match the manufacturer, model number, and AERC number in the certified product directory. Then read the Cool Climate or Warm Climate rating that fits your home's main heating or cooling need. Check blackout performance, fit, installation method, and any rebate separately.
What an AERC rating actually tells you
The Attachments Energy Rating Council, or AERC, runs a rating and certification program for products added to existing windows. Its residential Energy Improvement label gives certified products a Cool Climate rating and a Warm Climate rating. Supporting fields may include U-factor, solar heat gain coefficient, visual transmittance, and air leakage.
That is different from a broad claim about cellular shades as a category. The U.S. Department of Energy has published research showing that cellular shades can reduce heat transfer at windows under specific test and modeling conditions. DOE also tells consumers to look for the AERC label or search the certified product list when they need evidence for a particular product.
The distinction matters. Research can explain why a product type may work. A product-level rating tells you whether the exact model was evaluated through the certification program.
Read the AERC rating in five steps
1. Match the exact manufacturer, model, and AERC number
Start with the AERC Certified Product Search. Search for the manufacturer, product line, model number, or AERC number shown by the seller.
Close enough is not enough. A different fabric, opacity, control type, or model can have a different result. If a listing says only "AERC certified" without identifying the rated model, ask the seller for the label or directory record that matches the product in your cart.
The directory also lets shoppers filter by technical values. AERC notes that its certified products are simulated over a double-pane, clear window for the standard performance values, with other baseline-window options available in the search. That test context is one reason a rating should not be converted into a promised utility-bill reduction for every home.
2. Choose the climate column that matches your main need
The Cool Climate rating is the first number to examine when heating is the larger concern. The Warm Climate rating is the first number to examine when cooling and unwanted solar heat are the larger concern. In a mixed climate, both deserve attention.
This is not simply a border between northern and southern states. A home in Colorado may use substantial heating and cooling. A coastal Canadian home may have a different load from an inland home in the same province. Start with how the room and HVAC system actually behave, then use the label's climate guidance.
3. Read the score beside the category maximum
AERC shows a product's rating with a maximum for that product category. A higher number, closer to that maximum, indicates greater rated energy improvement for the selected climate. The maximum is important because product categories do not all have the same performance range.
Do not remove a number from its label and compare it as though every product uses one universal scale. Keep the climate column, product category, category maximum, and exact model together.
4. Separate typical use from automation
Some AERC labels show a typical-use rating and a separate result for automated operation. Automation can change the modeled result because the covering can follow a schedule instead of relying on someone to adjust it at the right time.
Compare the rating for the configuration you are buying. A motorized or automated score does not transfer to a manual version merely because the fabric looks the same. Likewise, a manual rating should not be presented as evidence for a home's actual operating schedule.
5. Use each technical value for the right question
The headline climate ratings are meant to simplify comparison, but the supporting values can explain why two products differ.
| Label field | What it describes | How to read it |
|---|---|---|
| U-factor | Heat transfer through the rated window-and-attachment setup | Lower values indicate less heat transfer |
| Solar heat gain coefficient | How much solar heat passes through the setup | Lower values admit less solar heat; the best choice still depends on climate and orientation |
| Visual transmittance | How much visible light passes through | Higher values admit more daylight |
| Air leakage | Air movement through the rated product setup | Lower values indicate less measured leakage |
| Cool Climate rating | Energy improvement when heating is the main concern | Compare the exact product with the category maximum |
| Warm Climate rating | Energy improvement when cooling is the main concern | Compare the exact product with the category maximum |
These measurements answer different questions. A low visual-transmittance value, for example, concerns daylight through the rated system. It does not describe every small light gap around an installed bedroom shade.
What Minnesota's policy means, and what it does not
The 2023 DOE article about Minnesota reported that the state added AERC-certified cellular shades to its Technical Reference Manual. The current Minnesota TRM page identifies version 4.2 as effective in 2026. That version's cellular-shade measure requires an AERC listing and minimum Warm Climate and Cool Climate ratings.
This is useful evidence that a state energy program can treat an independently rated shade as a measurable efficiency option. It is not a blanket endorsement of every cellular shade. It also does not mean that every Minnesota customer automatically receives a rebate.
The Minnesota Department of Commerce describes its TRM as a standard set of methods, inputs, and assumptions that program administrators may use. Utilities still develop and implement their own offerings. Before relying on an incentive, verify the current utility program, customer eligibility, exact product threshold, installation rules, purchase dates, and required documents.
This same rule of evidence applies outside Minnesota. A government article about one state, one product category, or one technical program does not certify an unrelated product.
U.S. and Canadian shoppers should verify different things
U.S. buyers can use the AERC label and directory to compare certified window attachments. A state or utility program may add its own thresholds, so directory inclusion alone may still be insufficient for an incentive.
Canadian buyers can use a legitimate product-level rating as technical information, but they should not assume that a U.S. certification creates Canadian rebate eligibility. Natural Resources Canada's ratings and certification guidance explains the Canadian performance terms and certification used for windows, doors, and skylights. Those primary-window ratings are not interchangeable with a window-attachment label.
For a Canadian purchase, ask three separate questions:
- Is this exact shade model listed in the AERC directory?
- Does the seller ship the same rated configuration to Canada?
- Does the applicable province, municipality, or utility recognize the product under its current rules?
If the third answer is unclear, contact the program administrator before ordering. A retailer's general energy-efficiency claim is not a substitute for written eligibility.
Energy rating, blackout, and fit answer different questions
One shade can address more than one problem, but the claims should not be blended together.
| Your question | Evidence to request | What does not prove it |
|---|---|---|
| Will this exact model improve window energy performance? | Product-level AERC label or other applicable independent test data | The word "cellular" or a reflective-looking layer |
| Will the room become very dark? | Opaque material plus evidence about edges, top, bottom, and corners | An energy rating by itself |
| Will it control light around the perimeter? | Side tracks, seals, frame details, exact fit requirements, and installed photos | A blackout fabric swatch alone |
| Will it fit this recess? | Measuring instructions, minimum depth, obstruction check, and correct dimensions | A generic "inside mount" description |
| Is the installation no-drill? | The product's current installation instructions | A cordless label or energy rating |
| Is it eligible for a rebate? | The current program's product list and customer rules | Government recognition of the category |
Blackout is a visible-light claim. Energy performance concerns heat transfer and solar gain. Fit affects how the covering behaves at the actual window. No-drill describes how it is installed. Cordless describes its operation and removes an accessible operating cord. None of those terms should silently stand in for another.
For a deeper look at category-level research, read Do Cellular Shades Save Energy? What DOE Data Shows. If the primary window may be damaged or failing, start with Window Attachments vs Replacement Windows before comparing shades.
Questions to ask before buying an energy-efficient shade
Save the answers with the product page or quote. They are much easier to check before payment than after installation.
- What manufacturer, product line, model number, and AERC number match this configuration?
- Is the rating for the same fabric, opacity, color range, and control type I am ordering?
- Should I prioritize the Cool Climate rating, Warm Climate rating, or both for this room?
- Is the number based on typical manual use or automated operation?
- Which baseline window was used for the published values?
- Does the product have a current directory record I can open myself?
- If a rebate matters, where is the current program rule that names the required product and threshold?
- What separate evidence supports the blackout and perimeter-fit claims?
- What recess depth, shape, and hardware clearances are required?
A seller who can answer those questions gives you something concrete to compare. A string of broad adjectives does not.
Where ShadeCort fits the decision
ShadeCort S is presented here as a light-control system, not as an AERC-certified energy product. Its verified design uses a custom-sized aluminum-alloy frame, enclosed side tracks, and an opaque horizontal dual-layer honeycomb panel made from non-woven polyester. An integrated reflective thermal layer helps reduce heat transfer, but there is no verified product-level AERC rating or promised energy-savings percentage in this article.
The system is manually operated and cordless. Its standard installation is no-drill for a compatible rectangular recess. The current measuring guide requires at least 1.18 inches, or 3 cm, of unobstructed recess depth and measurements at three points in each direction.
Choose ShadeCort when dependable total blackout, perimeter light control, custom fit, and a compatible no-drill installation are the main goals. If independently rated energy performance or program eligibility is the deciding factor, ask for the exact evidence and compare certified options before purchasing.
Watch the current ShadeCort installation video
The video shows how the current framed system fits into a compatible recess. Use it to inspect the installation method, frame position, and window-clearance needs. It does not demonstrate an energy rating.
The written installation guide provides the current assembly and fitting sequence.
A quick evidence check before checkout
Start with the outcome that matters most.
- For rated energy performance, verify the exact model and correct climate column.
- For total darkness, inspect the panel and the full perimeter.
- For a rental or drill-free project, verify the mounting method and lease requirements.
- For a difficult window, check recess depth, handles, locks, cranks, shape, and operating direction.
- For a rebate, confirm the live program rules before purchase.
This takes a few extra minutes, but it prevents one label from being asked to prove five unrelated things.
Sources and further reading
- AERC: Reading the Residential Label
- AERC: Certified Product Search
- U.S. Department of Energy: Interior Cellular Shades Boost Home Energy Performance
- U.S. Department of Energy: Minnesota Cellular Window Shades Policy
- Minnesota Department of Commerce: Technical Reference Manual
- Natural Resources Canada: Ratings and Certification
FAQ
What is an AERC rating?
An AERC rating is a product-level energy-improvement rating for a certified window attachment. The residential label includes Cool Climate and Warm Climate ratings and may also show technical values such as U-factor, solar heat gain coefficient, visual transmittance, and air leakage.
Is AERC the same as ENERGY STAR?
No. AERC certifies and rates window attachments such as shades, blinds, and storm windows through its program. ENERGY STAR has separate specifications for eligible product categories. Use the label and directory that apply to the exact product you are buying.
Does a higher AERC number always mean better?
A higher number closer to the category maximum indicates greater rated improvement for that climate column. Keep the product category, Cool or Warm Climate column, category maximum, operating mode, and exact model with the number when comparing products.
Are blackout cellular shades automatically AERC certified?
No. Blackout describes visible-light control. Cellular describes the material's hollow-cell construction. Neither term proves that the exact model has an AERC certification. Check the directory record.
Does an AERC-certified shade automatically qualify for a rebate?
No. A program can require a specific customer type, utility, product category, rating threshold, purchase period, installation method, or document set. Verify the current program before ordering.
Can Canadian buyers use an AERC rating?
They can use a valid rating as product-level technical information for the exact listed model. They should separately verify that the sold configuration is the same and that any Canadian provincial, municipal, or utility program recognizes it. A U.S. rating does not create automatic Canadian incentive eligibility.
Does ShadeCort have an AERC rating?
No verified AERC certification is claimed here for ShadeCort S. The product's supported role is custom-fitted total blackout and perimeter light control in a compatible recessed window. Buyers whose main goal is rated energy performance should request product-level evidence and compare certified options.
