Roof Measurements for Solar Installers: Facet Area, Pitch, Azimuth

Quick answerA roof measurement report supplies facet area, pitch, and azimuth (compass orientation) for each plane of the roof, plus total and per-facet square footage. It does not supply shading analysis, structural condition, or the exact position of vents, mounts, and setbacks on the ground. Usable facet area for a solar layout is the reported facet area minus obstructions, code setbacks, and any slivers too narrow to hold a row of modules, which is why installers pair the report with a site survey before finalizing a design.

What the report actually measures

A roof measurement report breaks the roof into facets, the individual sloped planes bounded by ridges, hips, valleys, and eaves, and reports the area of each one along with the total roof area. It also reports pitch per facet and, on most reports, the compass orientation (azimuth) of each facet's downslope direction.

That is a footprint-and-geometry deliverable. It tells you how much roof plane exists and which way it faces. It does not tell you what is sitting on that plane or what is standing next to it.

Pitch and the area math behind it

Reports calculate sloped area from a flat footprint using a pitch multiplier: multiplier = sqrt(rise squared + run squared) divided by run. A facet's footprint (its area as seen from directly above) is multiplied by this factor to get the actual sloped area a layout has to work with.

The table below applies that formula to common pitches. Use it to sanity-check a report's facet totals against the footprint, or to estimate sloped area quickly in the field before a report arrives.

Roof pitch	Multiplier	1,000 sq ft footprint becomes
3/12	1.031	1,031 sq ft
4/12	1.054	1,054 sq ft
5/12	1.083	1,083 sq ft
6/12	1.118	1,118 sq ft
7/12	1.158	1,158 sq ft
8/12	1.202	1,202 sq ft
9/12	1.250	1,250 sq ft
10/12	1.302	1,302 sq ft
12/12	1.414	1,414 sq ft

Multiplier = sqrt(rise^2 + run^2) / run, with run held at 12. Apply the multiplier for the facet's actual pitch, not an average for the whole roof; two facets on the same house often carry different pitches.

Azimuth: why the report's orientation number matters

Azimuth is the compass direction a facet faces, measured in degrees, with a south-facing plane in the northern hemisphere generally the most productive for a fixed array. A report's per-facet azimuth lets you rank facets before you ever visit the property, so you know which planes are worth a closer look and which ones are marginal by orientation alone.

Azimuth from a report is a geometric reading of the roof outline. Production modeling still has to combine that number with pitch, local latitude, and shading, which the report does not model.

Obstructions and setbacks: what to check before laying out modules

Roof vents, stacks, and chimneys
Each one removes usable area and forces a layout gap; a report's facet area does not subtract them unless the report format specifically flags penetrations.
Skylights and dormers
These break a facet into smaller usable sections and often change the practical shape available for a module row, even when the reported facet area looks large enough on paper.
HVAC units, satellite dishes, and antennas
Ground-mounted or roof-mounted equipment is rarely visible in a facet-level area figure and has to be confirmed on site or from current photos.
Fire code and access setbacks
Local fire code typically requires clear pathways along ridges, eaves, and valleys; usable area is the facet area minus these mandated setbacks, not the raw facet total.
Tree canopy and adjacent structures
Shading from trees, neighboring rooflines, or chimneys shifts throughout the day and season; a facet's area and azimuth say nothing about what shades it.
Decking condition and structural framing
A usable facet on a report can still be a facet that needs decking replaced or rafters sistered before it can carry an array; that determination is not part of a measurement deliverable.

What the report supplies versus what the site survey adds

Report supplies: total roof area, per-facet area, per-facet pitch, per-facet azimuth, and an outline of ridges, hips, valleys, and eaves.
Site survey adds: verified obstruction locations and dimensions, shading analysis across the day and year, decking and framing condition, electrical panel location and capacity, and confirmation that the roof covering has enough remaining service life to justify mounting hardware into it.
Neither one replaces the other. The report narrows down which facets deserve a site visit; the site survey turns that facet-level area into a buildable layout.

Ordering a report to start the takeoff

When a roof measurement is needed as the starting point for a solar takeoff, order by property address rather than scheduling a preliminary site visit just to get a footprint. Sketch My Roof roof measurement reports are delivered as PDF, and the same order also produces an ESX file for Xactimate® or an XML file for Symbility® when the roof work is tied to an insurance claim alongside the solar installation, for example a storm-damaged roof being replaced and fitted for solar in the same job.

Published pricing: Standard ESX $19, Complex-roof ESX $25 for cut-up roofs with many facets, PDF-only $25, ESX + PDF $29. Reports are ordered by address with no subscription and no minimum, and orders placed before the 6 PM Eastern cutoff deliver the same calendar day.

Frequently Asked Questions

Does a roof measurement report tell me which facets get the most sun?

It gives you pitch and azimuth per facet, which lets you rank facets by orientation before a site visit. It does not model shading from trees, adjacent structures, or the time of year, which is a site-survey task.

What is usable facet area for a solar layout?

It is the report's facet area minus code-required setbacks along ridges and eaves, minus space taken by vents, stacks, and skylights, and minus any section too narrow to fit a full module row. The report gives the starting area; the survey and layout software subtract the rest.

How is sloped facet area calculated from a flat footprint?

Area equals footprint multiplied by the pitch multiplier, where multiplier equals the square root of rise squared plus run squared, divided by run. A 6/12 pitch uses a multiplier of 1.118, so a 1,000 sq ft footprint becomes 1,118 sq ft of sloped area.

Can I use the same report for the insurance claim and the solar design?

Yes, if the job involves a claim-funded roof replacement ahead of a solar install. Order the report with both ESX (for Xactimate®) and PDF so one order serves the estimate and the solar takeoff starting point.

Do I still need a site visit if I already have a measurement report?

Yes. The report establishes area, pitch, and orientation. A site visit or survey is still needed to confirm obstructions, shading, decking condition, and electrical service before finalizing a module layout.

Sources

Published residential report formats and pricing: Standard ESX $19, Complex-roof ESX $25, PDF-only $25, ESX + PDF $29; order by address; no subscription; same calendar day delivery before the 6 PM Eastern cutoff: Sketch My Roof residential order page (as of August 2026)
Report formats: ESX for Xactimate®, XML for Symbility®, PDF; Xactimate® Integration ordering available for Verisk™ desks: Sketch My Roof roof measurement service facts (as of August 2026)
ESX import procedure into Xactimate® follows the vendor's documented import workflow; menus vary by version: Xactimate® official documentation (as of August 2026)
XML claims file handling follows Symbility®/CoreLogic documented procedures; menus vary by version: Symbility® / CoreLogic claims documentation (as of August 2026)

Roof measurements for solar installers