Editorial policy

Who writes this

Andrew Flores, working alone, with AI assistance used for drafting and checking and never as a source. Nathan Management publishes this site, and Andrew is the person who answers for what it says and makes corrections. Every registered figure traces to a named publication or a visibly labeled derivation or assumption, as described below.

What may be published as a number

Each cited figure on this site has an entry listing its value, unit, source, link, the supporting text from that source (a quoted sentence or transcribed table cells) and the date it was checked; the methodology page shows them all. Some numbers on the pages are not entries of their own: the state price tables, which name their source beside them, the values the tools calculate, and the example inputs each page names.

When a source page changes after a figure was taken from it, the figure is either re-sourced or kept as a historical figure with a visible label, the date of the copy it came from and a link to that copy. Each figure also carries a refresh date six months past the day it was checked.

Primary sources outrank aggregators

Physics, efficiency standards, test procedures and delivered energy prices come from federal primary sources wherever they exist. Installed-cost figures do not exist in primary form, so they come from commercial cost guides — and where that is the case, the methodology page says so and treats the figure as weaker evidence. All installed-cost bands here come from one commercial cost guide (HomeGuide); a second publisher (HomeAdvisor) supplies only the national average and range quoted on the home page.

Corrections

Errors are fixed at the source constant, which means every page using that figure updates in the same change. Corrections are recorded in the update log on the methodology page rather than made silently. Where a published source contains an error, that is stated openly with the discrepancy shown, instead of being smoothed over to make this site look consistent with a page that is wrong.

Independence and money

Nobody pays for placement, mention, ranking or a favourable comparison, and no manufacturer, installer or utility has reviewed anything here before publication. There are no affiliate links to contractors or products. If advertising is ever accepted it will be clearly separated from the content and disclosed on the privacy page in the same deployment that adds it — not afterwards.

Scope, honestly stated

This site publishes planning figures. It does not know your water chemistry, your local code, the state of your gas supply or what a contractor in your county charges on a Tuesday. Those are the things that actually decide your bill, and no calculator that has never seen your house can settle them.