The patio that disappears into its own glass after dark

Buy nothing yetMove the table before you buy the pergola.

Before you buy a pergola, move the table.

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 actually buys hours back is allowed to win.

Fixing

For

Reading at

11:00 PM·October

The sun is down.

Where it stands now

Sit outside after dark

We cannot say yet whether Outdoor sofa works for sitting out after dark, because privacy exposure is still unanswered.

“Unanswered” means missing evidence prevents a reliable verdict. The questions that need answering are listed below.

Past the limit What it feels like is about 46°F — 8°F under (at least 54°F)Estimate: Worked out, but at least one input was assumed rather than measured.
The air is 49.6°F. It feels about 3.6 degrees cooler than the air, near 46°F.
Radiant heat held by paving is what makes an evening terrace work at all.

Still unanswered:Privacy exposure

Why it is unanswered

Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

What would change this. This stays unanswered until privacy exposure is known. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

Confidence low (33%). Treat this as a starting hypothesis, not an answer.

What this answer was built from

Use: Sit outside after dark
Place: Outdoor sofa
Weather: Temperate maritime, mild, grey, damp (scenario shape), scenario (from a published source)
Method: Traced geometry and radiation at this hour, measured against what this use needs

The smallest thing that helps at this hour

A second seat 19 ft 8 in south

A second seat 19 ft 8 in south eases the hour without solving any single limit outright.

Summer solstice, 21 June: no usable hours then, with or without this change.

Winter solstice, 21 December: no usable hours then, with or without this change.

On this day: what it feels like is what keeps it shut, and air movement is the part that moves how it feels, with or without this change.

On the summer solstice: what it feels like is what keeps it shut, and air movement is the part that moves how it feels. With this change, nothing named keeps it shut.

No extra hours this daymove it

Nothing on the list buys extra hours on this day, so this is the least effort that still moves a limit.

Not offered, and why

Glare is not what is limiting this seat, so turning it changes very little.
No observer is marked, so there is no sightline to interrupt yet.
No observer is marked to screen from.
Wind is not the limiting factor at this spot, so a windbreak solves a problem you do not have.
Nothing overhead here to hang a curtain from yet.
Nothing here is low enough for a step up to see over.
Nothing here has usable space underneath it.
The sun is not up at this hour, so there is nothing to stand in front of.
There is no sun to shade at this hour.
No mature canopy here to work on.
There is no boundary here to build on.
No observer is marked to screen from.
No observer is marked to screen from.
No observer is marked to screen from.
Wind is not what is limiting this spot.
Wind is not what is limiting this spot.
Wind is not what is limiting this spot.
Wind is not what is limiting this spot.
Nothing here is relying on a deciduous canopy, so there is no winter gap to fill.
This point is a place for people, not a place for a plant.

20 changes, tested at 11:00 PM in October

One at a time, so you can tell what caused whatLook at the plan

Does it have to suit you?

All 20 changes, in the order the engine ranked them. Say something about your situation and the ones that would not suit you get set aside.

I rent, so nothing permanentRules out anything that cannot be taken away again.
Nothing that needs a builderRules out changes that need footings, trades or a structure fixing to the house.
I want it working this seasonRules out planting and anything else that only works once it has grown.
I will not maintain itRules out anything needing regular watering, pruning or seasonal putting away.

TestMove itYou can undo it

A second seat 19 ft 8 in south

ForecastUnansweredstill Unanswered

A second seat 19 ft 8 in south eases the hour without solving any single limit outright.

Put two chairs 19 feet 8 inches to the south 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.

Gained: Nothing here.
Lost: Nothing here.
Unchanged: What it feels like
Still unanswered: Privacy exposure

The test: A second seat 19 ft 8 in south
If it worked: The hour is easier, even if no single limit disappeared.
If it didn’t: If what it feels like still stops the hour after you try it, this was not the mechanism.
Next evidence: Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

+0 hours of usable time on this day.

Summer solstice, 21 June: no usable hours then, with or without this change.

Winter solstice, 21 December: no usable hours then, with or without this change.

Solstice hours are how long this use can happen on those days. The beam sentence is one clock time, and a different number.

On this day: what it feels like is what keeps it shut, and air movement is the part that moves how it feels, with or without this change.

On the summer solstice: what it feels like is what keeps it shut, and air movement is the part that moves how it feels. With this change, nothing named keeps it shut.

It does not meaningfully change the beam in either season.

TestMove itYou can undo it

Move the table 8 ft 2 in south-east

ForecastUnansweredstill Unanswered

Move the table 8 ft 2 in south-east eases the hour without solving any single limit outright.

Slide the seating about 8 feet 2 inches toward the south-east and change nothing else.

Gained: Nothing here.
Lost: Nothing here.
Unchanged: What it feels like
Still unanswered: Privacy exposure

The test: Move the table 8 ft 2 in south-east
If it worked: The hour is easier, even if no single limit disappeared.
If it didn’t: If what it feels like still stops the hour after you try it, this was not the mechanism.
Next evidence: Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

+0 hours of usable time on this day.

Summer solstice, 21 June: no usable hours then, with or without this change.

Winter solstice, 21 December: no usable hours then, with or without this change.

Solstice hours are how long this use can happen on those days. The beam sentence is one clock time, and a different number.

On this day: what it feels like is what keeps it shut, and air movement is the part that moves how it feels, with or without this change.

It does not meaningfully change the beam in either season.

TestMove itYou can undo it

Change Bright wall lantern to a warmer lamp

ForecastUnansweredstill Unanswered

Change Bright wall lantern to a warmer lamp does not move this in any way worth the effort.

Swap Bright wall lantern for a 2200 kelvin lamp of the same output. Blue-weighted light scatters more in the air, spills further into the garden and reads as harsher at the same brightness. Nothing structural changes; it is a lamp.

Gained: Nothing here.
Lost: Nothing here.
Unchanged: What it feels like
Still unanswered: Privacy exposure

The test: Change Bright wall lantern to a warmer lamp
If it worked: The hour is easier, even if no single limit disappeared.
If it didn’t: If what it feels like still stops the hour after you try it, this was not the mechanism.
Next evidence: Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

+0 hours of usable time on this day.

Summer solstice, 21 June: no usable hours then, with or without this change.

Winter solstice, 21 December: no usable hours then, with or without this change.

Solstice hours are how long this use can happen on those days. The beam sentence is one clock time, and a different number.

On this day: what it feels like is what keeps it shut, and air movement is the part that moves how it feels, with or without this change.

It does not meaningfully change the beam in either season.

TestAn afternoonYou can undo it

Shield Kitchen through glass

ForecastUnansweredstill Unanswered

Shield Kitchen through glass does not move this in any way worth the effort.

Fit a full cut-off shield to Kitchen through glass so the output goes down rather than sideways. The light on the table barely changes; the light on the neighbour's wall mostly stops.

Gained: Nothing here.
Lost: Nothing here.
Unchanged: What it feels like
Still unanswered: Privacy exposure

The test: Shield Kitchen through glass
If it worked: The hour is easier, even if no single limit disappeared.
If it didn’t: If what it feels like still stops the hour after you try it, this was not the mechanism.
Next evidence: Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

+0 hours of usable time on this day.

Summer solstice, 21 June: no usable hours then, with or without this change.

Winter solstice, 21 December: no usable hours then, with or without this change.

Solstice hours are how long this use can happen on those days. The beam sentence is one clock time, and a different number.

On this day: what it feels like is what keeps it shut, and air movement is the part that moves how it feels, with or without this change.

It does not meaningfully change the beam in either season.

TestAn afternoonYou can undo it

Two low shielded lights instead of one high one

ForecastUnansweredstill Unanswered

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.

Gained: Nothing here.
Lost: Nothing here.
Unchanged: What it feels like
Still unanswered: Privacy exposure

The test: Two low shielded lights instead of one high one
If it worked: The hour is easier, even if no single limit disappeared.
If it didn’t: If what it feels like still stops the hour after you try it, this was not the mechanism.
Next evidence: Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

It does not meaningfully change the beam in either season.

TestAn afternoonYou can undo it

Remove Kitchen through glass and mark the route instead

ForecastUnansweredstill Unanswered

Remove Kitchen through glass and mark the route instead does not move this in any way worth the effort.

Take out Kitchen through glass and put low shielded markers along the route in from the house. Being the brightest thing in a dark garden is the same as being on a stage, and the light that makes the step safe does not have to be the light you sit in.

Gained: Nothing here.
Lost: Nothing here.
Unchanged: What it feels like
Still unanswered: Privacy exposure

The test: Remove Kitchen through glass and mark the route instead
If it worked: The hour is easier, even if no single limit disappeared.
If it didn’t: If what it feels like still stops the hour after you try it, this was not the mechanism.
Next evidence: Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

It does not meaningfully change the beam in either season.

TestA projectYou can undo it

Raise the bed 1 ft 4 in

ForecastUnansweredstill Unanswered

Raise the bed 1 ft 4 in does not move this in any way worth the effort.

Build the bed up about 1 foot 4 inches with free-draining material. Roots sitting in water kill more plants than the wrong hardiness zone does, and lifting the root zone out of it is cheaper and far more reliable than trying to make the ground below drain.

Gained: Nothing here.
Lost: Nothing here.
Unchanged: What it feels like
Still unanswered: Privacy exposure

The test: Raise the bed 1 ft 4 in
If it worked: The hour is easier, even if no single limit disappeared.
If it didn’t: If what it feels like still stops the hour after you try it, this was not the mechanism.
Next evidence: Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

It does not meaningfully change the beam in either season.

TestA projectYou can undo itYears to work

A deciduous climber on tensioned wires

ForecastUnansweredstill Unanswered

A deciduous climber on tensioned wires does not move this in any way worth the effort.

Wires strung about 8 feet 6 inches 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.

Gained: Nothing here.
Lost: Nothing here.
Unchanged: What it feels like
Still unanswered: Privacy exposure

The test: A deciduous climber on tensioned wires
If it worked: The hour is easier, even if no single limit disappeared.
If it didn’t: If what it feels like still stops the hour after you try it, this was not the mechanism.
Next evidence: Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

It does not meaningfully change the beam in either season.

CommitmentA buildPermanent

A paler paving

ForecastUnansweredstill Unanswered

A paler paving does not move this in any way worth the effort.

Replace Dark wet 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.

Gained: Nothing here.
Lost: Nothing here.
Unchanged: What it feels like
Still unanswered: Privacy exposure

The test: A paler paving
If it worked: The hour is easier, even if no single limit disappeared.
If it didn’t: If what it feels like still stops the hour after you try it, this was not the mechanism.
Next evidence: Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

It does not meaningfully change the beam in either season.

CommitmentA buildPermanent

Relay it as a permeable surface

ForecastUnansweredstill Unanswered

Relay it as a permeable surface does not move this in any way worth the effort.

Relay Dark wet patio as permeable paving or resin-bound gravel over an open sub-base. Water goes down instead of sideways, so the spot dries hours earlier after rain and stops holding the film that makes it slippery and green.

Gained: Nothing here.
Lost: Nothing here.
Unchanged: What it feels like
Still unanswered: Privacy exposure

The test: Relay it as a permeable surface
If it worked: The hour is easier, even if no single limit disappeared.
If it didn’t: If what it feels like still stops the hour after you try it, this was not the mechanism.
Next evidence: Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

It does not meaningfully change the beam in either season.

CommitmentA buildPermanent

A ventilated timber deck instead

ForecastUnansweredstill Unanswered

A ventilated timber deck instead does not move this in any way worth the effort.

Replace Dark wet 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.

Gained: Nothing here.
Lost: Nothing here.
Unchanged: What it feels like
Still unanswered: Privacy exposure

The test: A ventilated timber deck instead
If it worked: The hour is easier, even if no single limit disappeared.
If it didn’t: If what it feels like still stops the hour after you try it, this was not the mechanism.
Next evidence: Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

It does not meaningfully change the beam in either season.

CommitmentA buildPermanent

Take up the paving and plant it

ForecastUnansweredstill Unanswered

Take up the paving and plant it does not move this in any way worth the effort.

Lift Dark wet 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.

Gained: Nothing here.
Lost: Nothing here.
Unchanged: What it feels like
Still unanswered: Privacy exposure

The test: Take up the paving and plant it
If it worked: The hour is easier, even if no single limit disappeared.
If it didn’t: If what it feels like still stops the hour after you try it, this was not the mechanism.
Next evidence: Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

It does not meaningfully change the beam in either season.

CommitmentA projectPermanentYears to work

A deciduous tree 23 ft west of the seat

ForecastUnansweredstill Unanswered

A deciduous tree 23 ft west of the seat does not move this in any way worth the effort.

A medium deciduous tree planted 23 feet to the west, grown to about 26 feet, with a crown roughly 19 feet 8 inches across.

Gained: Nothing here.
Lost: Nothing here.
Unchanged: What it feels like
Still unanswered: Privacy exposure

The test: A deciduous tree 23 ft west of the seat
If it worked: The hour is easier, even if no single limit disappeared.
If it didn’t: If what it feels like still stops the hour after you try it, this was not the mechanism.
Next evidence: Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

It does not meaningfully change the beam in either season.

CommitmentA buildPermanent

Horizontal fins above the opening

ForecastUnansweredstill Unanswered

Horizontal fins above the opening does not move this in any way worth the effort.

A run of fixed horizontal fins projecting about 2 feet 4 inches from 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.

Gained: Nothing here.
Lost: Nothing here.
Unchanged: What it feels like
Still unanswered: Privacy exposure

The test: Horizontal fins above the opening
If it worked: The hour is easier, even if no single limit disappeared.
If it didn’t: If what it feels like still stops the hour after you try it, this was not the mechanism.
Next evidence: Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

It does not meaningfully change the beam in either season.

TestAn afternoonYou can undo it

A 9 ft 10 in umbrella

ForecastUnansweredstill Unanswered

A 9 ft 10 in umbrella does not move this in any way worth the effort.

A 9 feet 10 inches canopy at about 7 feet 7 inches, set square over the table.

Gained: Nothing here.
Lost: Nothing here.
Unchanged: What it feels like
Still unanswered: Privacy exposure

The test: A 9 ft 10 in umbrella
If it worked: The hour is easier, even if no single limit disappeared.
If it didn’t: If what it feels like still stops the hour after you try it, this was not the mechanism.
Next evidence: Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

It does not meaningfully change the beam in either season.

TestA projectYou can undo it

A shade sail over the seating

ForecastUnansweredstill Unanswered

A shade sail over the seating does not move this in any way worth the effort.

A sail about 16 feet 5 inches by 13 feet 1 inch, set at about 9 feet 2 inches and angled to shed water.

Gained: Nothing here.
Lost: Nothing here.
Unchanged: What it feels like
Still unanswered: Privacy exposure

The test: A shade sail over the seating
If it worked: The hour is easier, even if no single limit disappeared.
If it didn’t: If what it feels like still stops the hour after you try it, this was not the mechanism.
Next evidence: Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

It does not meaningfully change the beam in either season.

CommitmentA buildPermanent

An adjustable louvred roof

ForecastUnansweredstill Unanswered

An adjustable louvred roof does not move this in any way worth the effort.

A louvred roof about 13 feet 1 inch square at 8 feet 6 inches, blades running north and closable.

Gained: Nothing here.
Lost: Nothing here.
Unchanged: What it feels like
Still unanswered: Privacy exposure

The test: An adjustable louvred roof
If it worked: The hour is easier, even if no single limit disappeared.
If it didn’t: If what it feels like still stops the hour after you try it, this was not the mechanism.
Next evidence: Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

It does not meaningfully change the beam in either season.

CommitmentA projectPermanent

An 8 ft 2 in awning

ForecastUnansweredstill Unanswered

An 8 ft 2 in awning does not move this in any way worth the effort.

A folding-arm awning projecting 8 feet 2 inches from the house wall at about 8 feet 6 inches, retracted out of season.

Gained: Nothing here.
Lost: Nothing here.
Unchanged: What it feels like
Still unanswered: Privacy exposure

The test: An 8 ft 2 in awning
If it worked: The hour is easier, even if no single limit disappeared.
If it didn’t: If what it feels like still stops the hour after you try it, this was not the mechanism.
Next evidence: Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

It does not meaningfully change the beam in either season.

CommitmentA buildPermanent

A solid canopy over the seating

ForecastUnansweredstill Unanswered

A solid canopy over the seating does not move this in any way worth the effort.

A solid roof about 11 feet 2 inches above the seating, 13 feet 1 inch by 11 feet 6 inches, guttered on the low edge. Unlike fabric it works in rain, and unlike a pergola it takes the winter light too.

Gained: Nothing here.
Lost: Nothing here.
Unchanged: What it feels like
Still unanswered: Privacy exposure

The test: A solid canopy over the seating
If it worked: The hour is easier, even if no single limit disappeared.
If it didn’t: If what it feels like still stops the hour after you try it, this was not the mechanism.
Next evidence: Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

It does not meaningfully change the beam in either season.

CommitmentA buildPermanent

A pergola with open slats

ForecastUnansweredstill Unanswered

A pergola with open slats does not move this in any way worth the effort.

A pergola about 13 feet 1 inch square at 8 feet 6 inches with open slats, slats running roughly north.

Gained: Nothing here.
Lost: Nothing here.
Unchanged: What it feels like
Still unanswered: Privacy exposure

The test: A pergola with open slats
If it worked: The hour is easier, even if no single limit disappeared.
If it didn’t: If what it feels like still stops the hour after you try it, this was not the mechanism.
Next evidence: Privacy exposure. No observer has been placed yet. Privacy is a question about who can see in from where, and until one is marked there is nothing to answer.

It does not meaningfully change the beam in either season.