Short essays on passive solar decisions
Clear thinking for passive solar design decisions before mistakes become expensive.
Most passive solar failures don’t come from bad simulations.
They come from unexamined early decisions.
Glazing ratios that seem reasonable.
Thermal mass added “just in case.”
Insulation levels copied from another climate.
Decision Notes exist to slow down these moments — and make their consequences visible before design directions harden.
Each note isolates one passive solar design decision and examines it through climate behavior, construction response, and long-term performance risk.
Why Decision Notes exist
Passive solar design is often discussed in terms of solutions.
More glazing. More mass. Better orientation. Smarter shading.
In practice, performance problems rarely come from missing solutions.
They come from unexamined decisions.
Decision Notes focus on the moment when a choice feels reasonable—but carries long-term consequences. They address questions such as:
- When does thermal mass improve performance — and when does it lock in overheating?
- Why does a passive solar strategy that works in one climate consistently fail in another?
- At what point does additional glazing stop contributing and start increasing risk?
- Why do highly insulated buildings often have less tolerance for passive solar gains?
Each note isolates one decision and examines it in context.
What a Decision Note is
A Decision Note is a short, structured essay that analyzes a specific passive solar design decision through the lens of:
- climate behavior
- construction system response
- site and operational constraints
- performance risk and trade-offs
Rather than offering prescriptive rules, Decision Notes explain how to think about passive solar decisions — what to evaluate, what to question, and where common assumptions fail.
The goal is not to provide answers, but to improve judgment.
What a Decision Note is not
A Decision Note is not:
- a checklist
- a climate-agnostic rule
- a performance guarantee
- a substitute for simulation
It is a thinking tool — used before optimization begins.
How Decision Notes fit into the methodology
Decision Notes are part of the same decision-first framework that underpins the Passive Solar Planning Toolkit.
They align with:
- the five passive solar climate profiles
- the four construction archetypes
- the Go / Proceed with constraints / High risk decision logic
While the toolkit formalizes decisions into structured tools, Decision Notes explore the reasoning behind them. Together, they form a coherent system:
Decision Notes shape thinking; the toolkit structures action.
Who Decision Notes are written for
Decision Notes are written for readers who influence early-stage design choices, including:
- architects working in concept and pre-concept phases
- consultants advising on performance strategy
- developers assessing feasibility and risk
- advanced self-builders seeking to understand constraints, not just options
They assume a technically literate audience and avoid simplification that obscures risk.
How to use Decision Notes
Decision Notes are most useful when read before committing to a design direction.
They can be used to:
- test initial assumptions
- prepare for feasibility discussions
- inform conversations with clients or consultants
- recognize patterns that lead to underperformance
They are intentionally concise, designed to be read alongside active project thinking rather than as reference material.
A shared principle
Every Decision Note is built around a single principle:
Early decisions matter more than late optimizations.
By examining those decisions in isolation, Decision Notes help prevent problems that no amount of refinement can fully resolve later.