nz housing is on the slippery slope of failure.

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#3356969 24-Mar-2025 19:30

k1w1k1d:

A properly designed and built house with insulation should not overheat. Huge windows and no eaves will cause a house to overheat.

Properly built as in has airconditioning. If its well insulated, 28 degrees outside then no building methods will make it reasonable inside. You are dumping heat into the place with all the power usage, and swapping that air for outdoor air will not help as its still coming in too hot.

Richard rich.ms

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#3356970 24-Mar-2025 19:32

neb:

with stays to prevent them from opening or openings that are just tiny slits in order to not affect the R-values

The stays are part of some BS kid safety thing for windows that a stupid kid could fall out of. People want nice low windows and regs end up putting those stupid things on them. Removal on your own house is a problem but its one of the things that rental inspections check are still in place because of landlord liability issues if someones stupid kid falls out and they have been defeated.

Richard rich.ms

tweake

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#3356972 24-Mar-2025 19:35

lxsw20:

I thought no eves died a death after leaky building became a thing, obviously not.

unfortunately no eves is part of the "modern" house look. ie looks before function. it seams to be a pretty common design theme, do the worse building practices in the name of looks. internal guttering is another one. at least branz has publicly said that should be removed from building code.

SomeoneSomewhere

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#3356974 24-Mar-2025 19:40

You essentially have two incompatible options:

1) Minimal insulation, lots of ventilation. Treat the house like a glorified shade cloth with high ceilings, wide-opening windows, and crossflow. No AC because it will spend a bunch of energy to do not much. Resulting indoor temperature approaches outdoor shade temperature, maybe a bit lower if you have lots of thermal mass. Expect siestas through summer in hot regions.

2) Lots of insulation and minimal heat gain, AC to reject the heat produced internally (lights, people, cooking, appliances etc.) and the remaining heat gain. Reasonable indoor temperatures can be achieved easily. This also works fairly well in winter for obvious reasons.

Attempting to combine the two options simply results in a property that can't be cooled naturally and can't be cooled mechanically.

mattwnz

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#3356980 24-Mar-2025 20:02

You can use the natural stack effect to naturally ventilate a house. We do this and have opening roof windows which get rid of the heat. It can work well if designed for. Also windows need to be shaded on the sunny sides of houses in summer to minimise the solar gain.

tweake

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#3356985 24-Mar-2025 20:07

SomeoneSomewhere:

You essentially have two incompatible options:

1) Minimal insulation, lots of ventilation. Treat the house like a glorified shade cloth with high ceilings, wide-opening windows, and crossflow. No AC because it will spend a bunch of energy to do not much. Resulting indoor temperature approaches outdoor shade temperature, maybe a bit lower if you have lots of thermal mass. Expect siestas through summer in hot regions.

2) Lots of insulation and minimal heat gain, AC to reject the heat produced internally (lights, people, cooking, appliances etc.) and the remaining heat gain. Reasonable indoor temperatures can be achieved easily. This also works fairly well in winter for obvious reasons.

Attempting to combine the two options simply results in a property that can't be cooled naturally and can't be cooled mechanically.

correct.

coming back the the news story, this is what the northland councilor and certain building industry members do not seam to understand.

i've had discussion about a passive house where they installed huge (very expensive) sliding doors which open up half the house. good homes (and passive house being the best) separate the indoor from the outside. opening up the house to the outside completely defeats the whole point of building a passive house. you can have one or the other, but not both.

richms

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#3356987 24-Mar-2025 20:10

mattwnz:

You can use the natural stack effect to naturally ventilate a house. We do this and have opening roof windows which get rid of the heat. It can work well if designed for. Also windows need to be shaded on the sunny sides of houses in summer to minimise the solar gain.

What temperature is the air coming into the house when you do this? How much dust and pollen comes in along with this air?

Richard rich.ms

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tweake

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#3356989 24-Mar-2025 20:13

mattwnz:

You can use the natural stack effect to naturally ventilate a house. We do this and have opening roof windows which get rid of the heat. It can work well if designed for. Also windows need to be shaded on the sunny sides of houses in summer to minimise the solar gain.

yes thats fine, if its 1970.

but we don't build like that anymore. just ask anyone with a pollen allergy. we don't want all that dirty contaminated air flowing through fouling the house. also at best you can only naturally cool down to outdoor air temp.

we go inside to get away from the dirty air, go inside to get out of the heat, go inside to get away from the cold, go inside to get away from the rain. good homes are all about separation from the outdoors.

neb

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#3357046 24-Mar-2025 20:56

SomeoneSomewhere: 2) Lots of insulation and minimal heat gain, AC to reject the heat produced internally (lights, people, cooking, appliances etc.) and the remaining heat gain. Reasonable indoor temperatures can be achieved easily. This also works fairly well in winter for obvious reasons.

This place has huge amounts of insulation and stays very cool during the day so when you come home you walk into 22 degree air when it's 28 degrees outside and the roof temperature at 50 degrees. Even with people then present it only needs very minimal AC to keep it cool after that, it's not like we're running a 2kW oil column heater in the middle of the living room.

gzt

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#3357051 24-Mar-2025 21:11

k1w1k1d: A properly designed and built house with insulation should not overheat.

Many apartment style dwellings are specified and built with recirculating rangehoods. Hopeless. There is no external vent. Heat returns to the living space.

gzt

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#3357061 24-Mar-2025 21:17

It has been a while since I lived in an apartment. If I remember correctly the bathroom fan had an exactly similar side effect.

tweake

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#3357062 24-Mar-2025 21:17

gzt:

Many apartment style dwellings are specified and built with recirculating rangehoods. Hopeless. There is no external vent. Heat returns to the living space.

and so does all the pollutants. cooking is one of the biggest generators of pollution inside a house.

however doing vents on high rise buildings comes with challenges as each level is at a different pressure.

gzt

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#3357063 24-Mar-2025 21:20

tweake: however doing vents on high rise buildings comes with challenges as each level is at a different pressure.

It is a simple design challenge. There is more than one way to solve it.

A solution that requires additional air-conditioning to remove the additional heat vented into the dwelling is not sensible.

neb

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#3357064 24-Mar-2025 21:22

gzt: Many apartment style dwellings are specified and built with recirculating rangehoods. Hopeless. There is no external vent. Heat returns to the living space.

Is it "specified with" or just "the builders stuffed the other end of the duct into wherever there was a gap"? I've seen several of those, what looks like ventilation but that doesn't vent anywhere.

SomeoneSomewhere

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#3357077 24-Mar-2025 22:25

Rangehood exhausts really don't remove that much heat, especially if you're not using gas. Again, ventilation, stack effect, whatever cannot get you below outside air temperature, unless you have a metric f***ton of thermal mass and use ventilation to chill it overnight - you're just using a longer average of 'ambient'.

But the vast majority of high-rises I've dealt with have had decent ventilation; better than single dwellings or medium density.

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