Questions tagged [building-physics]
The application of physics to the built environment, particularly with regard to the movement of heat, air, moisture, pollutants and light through buildings.
43 questions
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At what point would the strongest material break under its own weight?
Is there a chart or a way to calculate the breaking point of a material such as spider wire made from Aerographene, 3D-Structured Graphene, or Metallic Microlattices under its own weight?
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Mechanics of an elevator bed/platform in a Tiny House
I'm building a Tiny House that will have a platform that moves about 1 meter up and down. Given that I have little to no experience using pulleys, cogwheels or any of the like, I'd like some feedback ...
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Building orientation - how come both summer and winter solstice used for a facade?
I am planning to build a shed atop my terrace. I was analyzing the sun path to determine the overhang length, facade height etc, but got stuck with a conflict as below.
The summer sun's location peaks ...
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Is destratification ventilation more efficient at ceiling level?
This question is more of a practical physics question. In buildings with heating systems, heated air tends to rise and create air temperature stratification - hottest air near the ceiling, coldest air ...
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How much do I need to trickle my faucet in cold weather (as a function of x,y,z)? [closed]
I am told that, in cold weather, I should let my faucet trickle a little to prevent pipes from freezing, especially if some portion of my above-ground pipes are likely to get cold.
Are there any rules ...
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How does the tuned mass damper on Taipei 101 work?
I'm interested in how the tuned mass damper on the top floors of Taipei 101 works, particularly how do engineers ensure that it dampens oscillation rather than making it worse.
The damper can be ...
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When a skyscraper sways in the wind, in which direction is the motion?
Skyscrapers sway in the wind (Source here). Which direction, relative to the wind, do they sway, ignoring effects of other buildings nearby?
I can imagine wind from the North blowing a skyscraper's ...
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Proportion of heat or energy passing through a window by radiation vs conduction
I'm trying to understand how modern window films or coating (so-called "Low-E" coatings) can improve the "R" value of the window just by reflecting internal room radiant energy (presumably long-wave ...
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Why was the glass broken in the Lobby but not above the impact zone? - 9/11
Disclaimer: I do thoroughly believe that 9/11 was a terrorist attack, so please don't start arguing whether it was an attack or inside job, focus on the question.
Also: I was about to post this in ...
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How to construct a 12-micron thin layer of powder+epoxy?
Okay, this is more of an engineering tactic question perhaps, but any insight into any possible process will be very, very appreciated. So I'm mixing a powder with epoxy, making a pasty, fluid semi-...
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The Perfect Bridge [closed]
Is it possible to calculate the amount of weight a perfectly designed bridge(not necessarily known) can hold given certain parameters and under ideal and perfect conditions:
amount and type of wood
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if a building sways because of a constant wind will it sway back past its equilibrium [closed]
If I have a building that acts analogous to a spring at equilibrium and a constant wind comes from the north forcing the building to sway to the south will the building ever sway back towards the ...
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processes that cause heat loss in buildings [closed]
I'm looking for a fair study in which they assessed the importance of different processes that cause overall heat loss in buildings. With processes i mean convection, radiation, conduction trough the ...
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Why do tall buildings have low resonant frequencies?
I know that tall buildings have low natural frequencies, hence they're more vulnerable to earthquakes, but why do they have low natural frequencies?
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What is "hydrostatic uplift pressure"?
I was reading Wikipedia about the St. Francis Dam and came across this sentence.
Water that collected in the drainage pipes under the dam to relieve
the hydrostatic uplift pressure was carried off ...
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If I replace all my lights with LEDs will my heating costs increase?
A number of nations are passing bills to phase out incandescent light bulbs. The thinking is that the tungsten filament is an inefficient method of turning electricity into light, the rest of the ...
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Why is an air conditioner more efficient in a low-thermal-mass house?
Why is an air conditioner more efficient in a low-thermal-mass house?
I recently read
To get these efficiency gains it is important to use the air
conditioner as it is intended: the unit has to ...
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Water flushed down, water pumped up (in buildings)
I live in a tall building (20 floors) on a mountain. Because the water pressure from the water company is not enough, there is a water pump at the last floor which is activated each time someone is ...
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Air velocity in a double-skin facade
I was wondering how the air flows in a double skin facade? Say I have a glass facade with a depth of 1m, a height of 200m and a width of 10m. It is a single vertical shaft all the way up with openings ...
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Which direction does air flow?
I remember learning this in high school, but have forgotten it, and can't seem to find it anywhere online.
Air travels from areas of high pressure to low pressure...correct? So if I have a cold room ...
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What instrument will measure voids in a brick wall non-destructively?
Let's take what's ostensibly a solid brick wall. It looks solid from the front and the back. It's typically at least two widths of brick thick, plus some. What techniques could we use to non-...
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What devices could be taken round dwellings to measure the thermal conductivities of buildings in situ?
Your lateral thinking and knowledge of lab kit could help us solve a tricky measuring problem in building-physics.
One of the problems we get in modelling the heat demands of buildings, is getting an ...
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