Would anyone like to discuss indoor climate?

We live in houses, and work in buildings such as offices, factories and warehouses, because these structures protect us and our furniture and equipment from the weather outdoors.

The control of climate in commercial buildings may not interest many Weatherzone readers, but houses may attract discussion. How well does your house protect you from extremes of climate? Have you improved it by DIY projects? Have you measured the indoor climate to compare with the outdoor climate? How have you coped with instrument problems?

My own special interest is my solar-passive house. I live inland, where seasonal and daily temperature extremes are far beyond the comfort range. I now have a lot of data showing how well the house reduces these extremes.

This would indeed be a very interesting topic, only I doubt too many people would have indoor data. One thing that could be observed from an ongoing dataset would be the effect of outside weather changes on the temperature indoors, as well as when people turned on their heating/cooling...perhaps reflecting the people's comfort zones and when those zones were being violated by changes in the weather.

I can certainly relate to indoor conditions in industry; I worked in an office for over 38 years and the ability of the airconditioning system to spread respiratory infections was always something I was having battles with!

Actually, Keith, some people may have simply failed to record available data. "Indoor/outdoor" thermometers are very popular. It is just a matter of noting down the readings.

Exactly!
And I hope they have. It would be quite interesting to see what people have recorded/noted etc.
:cheers:

lol, my fridge has a thermometre.....house has a very big vary in temp - reaching 35+ in summer and sometimes sitting on 11 for days in winter

Actually, come to think of it, I've had indoor/outdoor thermometers monitoring my fridge years. It actually detected when the thermostat failed once..I would never have known as quickly otherwise.

Percy, I have some data from an "ordinary" house next door. Daily max temps indoors are practically the same as outdoors. Daily indoor minima are about 5 deg warmer than outdoors.

Interest seems to have waned on this one.

For what it's worth, here is something that may not seem to refer to the topic, but I think it does.

Last week I improved the indoor climate of my house by pruning trees.
The house is in its winter regimen: the big north windows are now admitting sun all day, and the floor slab and internal brick walls are storing the heat.
There are four self-sown olive bushes (Olea europaea) about 10 m NW of the house. I pruned them heavily in May two years ago, but they have since grown to a dense leafy mass about four metres high and twelve metres wide. In summer this was helping to keep the house cool. They shaded a lot of ground, they cooled themselves by transpiration, and they intercepted long wave radiation.
Now that the sun has moved north, the bushes have begun casting shadows on the north windows in the afternoon. I have pruned each bush back to about two metres high and two metres wide. Very little of the house is now shaded, just before sunset. Not only is a lot more solar radiation coming through the windows, but the soil surface under the bushes is reflecting and radiating heat towards the house.
The bushes will grow back again. I may leave them unpruned for two summers. That way the house gets really good shade in the second summer, and really good solar gain the following winter.

Tress around my house make an enormous difference to the internal temperature in summer - it takes 3 days of +36°C temps to get the house temp up to 'uncomfortable'. On hot days, all curtains are drawn, all windows closed and all internal doors closed until evening. I monitor internal/external temperatures and as soon as the external temp drops below the internal - every door and window is opened and the fans are turned on - the house is designed well enough to get fairly efficient cross draughts going. Not often that I 'need' the airconditioner and never sleep with any more than a fan.

In winter I'm guilty of not closing curtains except in bedrooms - unless it's seriously cold outside (we are talking 1°C or less here) - I hate feeling shut in. The trees in the vicinity of the house also help to keep the temperature in the area reasonable - I have never had a frost in the backyard even though there was one across the street. The trees on the west are deciduous (elder and pinoak) while the trees on the north are eucalypts, but tall enough to allow the sun into the house in winter, but not summer.

The temperature on the external south side is usually 2 - 3°C lower than that on the west - the latter thermometer picks up any northerly component of the wind.

I have put up shadecloth over the pergola on the west - the only part that gets direct afternoon sun in summer - that solved that problem and also the 'cold' fern syndrome that I had early on - ther fern garden there also allows me to water foliage next to the house which then works like a Coolgardie safe and cools the house.

WoodGully2

I would not be nearly so regular about opening and closing curtains if I had not used motors and a clock. Expensive, but very effective, and they have lasted 7 years so far.

Eucalypts and native shrubs are already starting to form a summer shade barrier on the east and south-east.

I also open the windows and doors on summer evenings when the outdoor temperature gets lower than indoors. Unfortunately that is commonly after eleven pm.

This time of year, late May to early June, is when an un-heated solar-passive house with a heat bank makes the greatest improvement to comfort.

Yesterday's figures for example:

Indoor Outdoor Diff.

Max. 25 20 +5
Min. 20 0 +20
Mean 23 10 +13
Range 5 20 -15


Indoors, it was very comfortable all day; outdoors only the early afternoon was comfortable.

funny you talk about monitoring inoor climate data,
my davis weather station has been measuring indoor
temp. and humidity every 15 mins since i've had the
system by default. since oct 2002 in our new house,
its a log cabin house, had many years of data for
our previous house which was an old solid freestone
house. would have been good to compare the two but
the data for the previous house seems to have gone
to cyberspace heaven. i know i didn't roll it over
when i installed the station on the new house, i
saved it, just dont know where atm.
i also have one of those 2 foot diameter industrial pedistal
fans that i sit at the back door on hot sumer nights to
pump cool fresh air through the house, even on low
it turns over the entire volume of air in the house every 3 mins.
i'm also currently building a sump oil fired thermostatically
controlled furnace\heat exchanger to take fresh
air from outside and pump large volumes of warm fresh
air into the house during winter.
i'v had acsess to thousands of
gallons of sump oil every year which normally go to
Adelaide to be burnt in furnaces up there and i decided
there is way too much free energy there not to do
something about it.

TH

Hi Thunda Hunta

Does your station have software for summarising data?

Software programs such as weatherlink (designed by Davis) will record all weather parameters at intervals of your choice. So in Thunda Hunta's case, every 15min.

Jello

Just getting a record is only the first step.

I put my manual records in Excel. This allows me to do many kinds of analysis, and make charts.
Excel charting programs are very flexible but they do have hidden glitches.

I download temperature data from the Tamworth METAR on weatherzone. It copies straight into Excel, where I can plot it on the same chart with my own observations. There is one annoying defect: the date/time is formatted as text. I have to make a new data column and manually enter it in date/time format, which is actually stored as a single number. (A few seconds ago was: 38505.5582043981)


So my question is whether Davis provides software to do analysis, rather than logging. Alternatively, are the records easily copied to Excel?

This is the time of year (August) when a solar-passive heat-bank house has to work hardest to keep the indoor climate warm enough.

The north-facing windows admit similar quantities of heat each month through the winter. At the solstice the sunshine penetrates furthest into the house, but the day is shorter. Now there is less penetration, but a longer day.

Air-mass temperatures have warmed up a bit, but the temperature of the land mass is at its minimum. Frosts are at their most severe.

In mid-August the subsoil in my garden was down to a minimum of 11.9 degrees. The subsoil under the house (protected by perimeter insulation) runs about 5 degrees warmer all winter, and is now just rising from a minimum of 17.6 degrees. The floor seldom gets much cooler than the sub-soil beneath it.

August 14 was about as cool as my house got this year:

Temp.; Indoor; Outdoor; Diff.
Maxim; +18.50; +15.60; +02.90
Minim; +15.60; -00.70; +16.30
Mean.: +17.05; +07.45; +09.60
Range; +02.90; +16.30; -13.40

RH Max; 38.0%; 88.0%; -50.0%
RH Min; 34.0%; 37.0%; -03.0%
RH Mean 36.0%; 62.5%; -26.5%
RH Rge; 04.0%; 51.0%; -47.0%

I used no heating that night, but the previous week I used a 2kW blower heater for a total of 7 hours. In June and July I used the heater for 26 hours, so the total heating cost so far this winter is about $10. Fans moving warm air around for 300 hours cost about $2.

It is often said that the air inside a house will usually be more humid than that outdoors. That is certainly not true in this case!

ive got indoor and outdoor data but my indoor is heavily affected by a ducted air con most of the time

Hi Surly Bond;
I bought two books about 10 years ago from the Commonwealth Bookstore in Sydney.

They detail a lot about indoor/outdoor comfort.

The first book is Sunlight at Work; with shadow lines; sunpaths etc over Aust. Esp home/windows shades etc.

The second book is called Thermal comfort at work; which is to do with both work & home environments.

The are both from the AGPS.

You may find it in a library or a online book search. It is very interesting with a lot of details of comfort for homes for both winter & summer

Yes, boardrider, once you have an air conditioner it does its own thing. There is not much point in measuring the climate unless you think the machine is faulty. A powerful enough air conditioner will force an "ideal" climate regardless of the design of the house.


Tony, I haven't come across either of those books yet. I have several books that tell me rather more than I want to know:D , especially:

"Introduction to Architectural Science: the Basis of Sustainable Design" by Steven V Szokolay (Elsevier, 2004) ISBN 0 7506 58495,

"Energy Efficient Building Design Resource Book" by Holger Willrath (Renewable Energy Centre, Brisbane Institute of TAFE, 1992, 2000) ISBN 1 876880 03 1

last night with no air con on it down to 12.5 inside and 5.4 out side so my house definately isnt as effective at keeping heat as yours surly bond.i only measure indore climate because its part of my weatherstation ans my PC keep records on weather display live