Solutions
Whole-home energy audit
Blower door, thermal scan, combustion safety and a room-by-room Manual J load, in one visit, with the numbers written down.
- Audit fee
- $395 for homes to 2,500 sq ft
- Time on site
- 3 to 4 hours
- Typical ACH50 before
- 8 to 14 for pre-1990 Boulder County homes
Energy auditsHow we think about it
Energy audits, in plain terms
The audit is where we start with nearly every customer, because it is the only way to know whether you need a bigger array or a tighter house. A 1978 ranch in Longmont leaking 11 air changes per hour at 50 pascals does not need 14 kW of solar. It needs 40 hours of air sealing and then 7 kW.
We run a calibrated blower door to get ACH50, walk the envelope with a thermal camera while the house is depressurised, measure duct leakage where ducts run outside the thermal boundary, and do a combustion safety check on every atmospherically vented appliance. Then we build a room-by-room Manual J heating and cooling load against Boulder's 99 percent winter design temperature of about 2 degrees F.
You get the raw readings, not a score. ACH50 before and the modelled ACH50 after. Attic R-value measured, not assumed. Design heating load in Btu per hour. Every recommendation carries a cost, a modelled saving in therms or kWh, and a simple payback.
On the quote, not in a change order
What is included
- Calibrated blower door test, ACH50 and CFM50 recorded
- Thermal imaging sweep of the envelope under depressurisation
- Duct leakage test where ductwork sits outside the thermal boundary
- Combustion safety and CO check on every atmospherically vented appliance
- Insulation depth and type measured in attic, walls and rim joist
- Room-by-room Manual J heating and cooling load
- Written report with costed measures, modelled savings and payback
- Rebate paperwork prepared for the programmes you qualify for
Start to finish
How the work runs
- 01
Walkthrough
Forty minutes on the house history: age, past work, cold rooms, high bills, anything that smells or sounds wrong.
- 02
Blower door
We depressurise to 50 pascals and record CFM50, then convert to air changes per hour against the conditioned volume.
- 03
Thermal sweep
With the house under pressure, cold air pulled through gaps shows up clearly on the camera. Top plates, rim joists, can lights, attic hatches.
- 04
Mechanicals
Duct leakage, static pressure, combustion draft and CO. If something is unsafe we tell you on the day, not in the report.
- 05
Report
Within five business days: measured readings, Manual J load, costed measures ranked by payback, and rebate paperwork started.
Why it is worth doing
Three things you get that a cheaper quote will not give you
- 01
Stops oversized equipment
A real Manual J routinely comes in 30 to 40 percent below the rule-of-thumb sizing, which means a smaller heat pump and a smaller bill.
- 02
Unlocks rebates
Most Boulder County and utility efficiency rebates require a pre-work audit from a certified auditor. Ours counts.
- 03
Credited back
The full audit fee comes off any GreenLeaf install over $6,000 signed within 90 days (sample offer).
Asked on nearly every visit
Questions about this work
More on the questions page, or call the shop and ask a person.
Air changes per hour at 50 pascals of depressurisation. It is a standardised leakiness measure. A house at 12 ACH50 is replacing its entire air volume twelve times an hour under test conditions, and it is why the back bedroom is cold.
We will tell you what the house needs in order of payback. On leaky pre-1990 homes that is almost always air sealing and insulation first, solar third. Selling you an oversized array to heat the outdoors is not a business we want.
No. Measures are ranked by simple payback so you can draw a line wherever your budget sits. Most people do the first three in year one.
Yes. Fifty pascals is about the pressure of a 20 mph wind against one wall. We do check for loose ash, vermiculite and disconnected flues before we start.
Usually bought together
What else this touches
Insulation and air sealingSeal first, then insulate. Attic to R-60, rim joists closed, and the ACH50 re-tested so you can see it moved.
Heat pumpsSized from a real Manual J and specified at 5 degrees F, not at the 47 degree rating on the brochure.
Rooftop solarArrays between 5 and 12 kW DC, sized from twelve months of your own kWh rather than from your roof area.
Start with the test, not the quote
Three to four hours on site, a written report in five business days, and a recommendation that might well be to spend less than you planned.