The July fix that February will hate
Every change below is put into the plan and the whole model is run again. That is why a pergola's winter cost shows up here without anybody having written it down, and why the cheapest thing that works is allowed to win.
Reading at
Dinner outside
What it feels like is2.9°F over— 85.3°F against at most 82.4°F
Nobody finishes a meal in a seat that is cooking.
Glare is1 over— 29 / 100 against at most 28
You cannot look at the person across the table with the sun behind their head.
Confidence low (38%). Treat this as a starting hypothesis, not an answer.
Face the seating south fixes glare.
Ranked by what solves the actual limit with the least effort, not by the biggest number.
Not offered, and why
Horizontal fins above the opening fixes what it feels like and glare.
A run of fixed horizontal fins projecting about 2.3 feet from South-facing house, set above head height. Geometry does the work: high summer sun is cut, low winter sun passes under, and the view out is barely touched.
+0 hours of usable time on this day.
It does not meaningfully change the beam in either season.
A 13.8 ft umbrella fixes what it feels like and glare and costs you wetness.
A 13.8 feet canopy at about 7.5 feet, tilted toward the low sun.
+0 hours of usable time on this day.
It takes the summer sun and leaves most of the winter sun, which is the behaviour worth paying for.
A deciduous tree 16.4 ft west of the seat fixes what it feels like and glare and costs you wetness.
A medium deciduous tree planted 16.4 feet to the west, grown to about 26 feet, with a crown roughly 19.7 feet across.
+0 hours of usable time on this day.
It takes the summer sun and leaves most of the winter sun, which is the behaviour worth paying for.
A 8.5 ft panel to the west fixes what it feels like and glare and costs you wetness.
A solid panel about 8.5 feet high and 9.8 feet wide, standing 7.2 feet to the west. Low sun arrives almost horizontally, and only something vertical stops it.
+0 hours of usable time on this day.
It does not meaningfully change the beam in either season.
A 11.5 ft awning fixes what it feels like.
A folding-arm awning projecting 11.5 feet from the house wall at about 8.5 feet, retracted out of season.
It takes the summer sun and leaves most of the winter sun, which is the behaviour worth paying for.
Face the seating south fixes glare.
Turn the chairs to look south, which puts the low sun behind the shoulder instead of across the table.
It does not meaningfully change the beam in either season.
Move the table 8.2 ft north-east improves things by 5 points without solving any single limit outright.
Slide the seating about 8.2 feet toward the north-east and change nothing else.
It does not meaningfully change the beam in either season.
Two 8.2 ft parasols instead of one improves things by 5 points without solving any single limit outright.
Two parasols about 8.2 feet across, set 7.2 feet apart along the table. Between them they cover a rectangle, which is the shape a table actually is.
It does not meaningfully change the beam in either season.
A second seat 19.7 ft east improves things by 4 points without solving any single limit outright.
Put two chairs 19.7 feet to the east and leave the main table where it is. The point is not to fix this spot but to stop needing it at the hour it does not work.
It does not meaningfully change the beam in either season.
Two low shielded lights instead of one high one does not move this in any way worth the effort.
Add a pair of shielded 200 lumen fixtures at knee height near the seating, so the useful light is where people are rather than thrown across the garden.
It does not meaningfully change the beam in either season.
A shade sail over the seating improves things by 4 points without solving any single limit outright.
A sail about 16.4 feet by 13.1 feet, set at about 9.2 feet and angled to shed water.
It takes the summer sun and leaves most of the winter sun, which is the behaviour worth paying for.
A pergola with close-spaced slats does not move this in any way worth the effort.
A pergola about 13.1 feet square at 8.5 feet with close-spaced slats, slats running roughly north.
It takes the summer sun and leaves most of the winter sun, which is the behaviour worth paying for.
Take up the paving and plant it does not move this in any way worth the effort.
Lift South patio and plant it. Nothing else on this list moves surface temperature as far: paving in full sun sits twenty degrees or more above the air, while planted ground transpires and typically sits at or below it. It is also the only change here that gets better rather than worse over ten years.
It does not meaningfully change the beam in either season.
A solid canopy over the seating does not move this in any way worth the effort.
A solid roof about 11.2 feet above the seating, 13.1 feet by 11.5 feet, guttered on the low edge. Unlike fabric it works in rain, and unlike a pergola it takes the winter light too.
It does not meaningfully change the beam in either season.
A ventilated timber deck instead does not move this in any way worth the effort.
Replace South patio with a ventilated timber deck. Heavy paving charges all afternoon and radiates back until well after dark, which is why an evening terrace can feel hotter than the air. A light deck over an air gap is done within the hour.
It does not meaningfully change the beam in either season.
An adjustable louvred roof does not move this in any way worth the effort.
A louvred roof about 13.1 feet square at 8.5 feet, blades running north and closable.
It takes the summer sun and leaves most of the winter sun, which is the behaviour worth paying for.
A paler paving does not move this in any way worth the effort.
Replace South patio with a paler paving of similar mass. The surface itself runs cooler underfoot; the trade is that more light bounces back up at a seated person.
It does not meaningfully change the beam in either season.
A deciduous climber on tensioned wires does not move this in any way worth the effort.
Wires strung about 8.5 feet above the seating with a vigorous deciduous climber trained across them. In leaf it shades like a light pergola; bare, it gives back most of the winter sun a solid roof would have kept.
It does not meaningfully change the beam in either season.