How hot is your shed?

[Bizibilder]

A few folk have commented on the problems(?) of high temperatures in observatories, especially on sunny days. So I thought I would record a few readings of my own tin shed:

My Observatory is a 6'6" x 6'6" metal shed. It stands in my garden and gets the Sun pretty much all day. The West wall is shielded from the Sun by a fence. The outside temp is that recorded at around 4pm and the inside temp is from a max-min thermometer that lives in a drawer in the observatory. Over the last three days the temperatures inside and out have been:

Tuesday 22 May: Outside 18°C Sunny/hazy all day (cool easterley breeze) In the shed max = 20°

Wednesday 23 May: Outside 21°C Sunny all day (slight breeze) In the Shed max = 24°C

Thursday 24 May: Outside 24°C Sunny/hazy all day (Dead calm) In the Shed max = 26°C

Not very scientific but it may give folk an idea of what to expect.

[Macavity]

In all honesty, pretty hot! With hindsight, painting a wooden (Alexanders) Roro observatory "Dark Oak" may not have been my master stroke. LOL. But it LOOKS cool! With an ambient temp ~24 deg, it was ~29 deg inside, with roof closed. I was a bit surprised that a mere colour change (from default "ginger"!) made such a difference. But it still seems to radiate (as a "black body"?) the daytime heat pretty well... especially if I leave the roof open as it gets dark.

Speculation: I guess there's a reason why Dome Observatories (and Cricket Pavillions!) are White? A DARK coloured wooden observatory may experience greater temperature variations? The expansion / contraction (cracking!) may not be great for wood longevity? I sense, if you're a Solar observer "Red Hot" walls may not be too good either! On the other hand, nice warm non-metallic observatories don't seem to suffer from (rumoured) Dewing Problems of grey metal sheds?

[Paul Laws]

VERY!

I've not measured temps but standing in there for 5 minutes is akin to taking a sauna when the doors are shut.

I was initially concerned as the variances according to seasons is phenomenal. I was a little 'precious' about the kit when new but now I see it as 'stress testing'

My shed is a plastic Keter type. A large, slightly *underfed, dog has a kennel to the side of it

Regards.

* A false statement but one made to emphasise a 'keen' guard dog.

[spaceboy]

I noticed my obs was running the mercury at 35° while the outside temperature was 30° the other day. The construction is mostly UPVC clad OSB board and an aluminium domed roof.

[yesyes]

The graph below shows the temperature inside my shed for the last 7 days.

It is a brick shed with a flat, black rubber covered timber roof. (It's not an observatory)

[iwatkins]

Solar imaging yesterday from inside my shed (actually is a shed, all wood) and outside temps 26C but inside was 34C. Was so hot I was dripping sweat into my glasses

Things you do for a bit of shade on your monitor eh?

[lukebl]

35 degrees C in mine right now.

[malc-c]

Just checked at 13:30 BST

Observatory had been shut up all day (I've popped home from work for lunch)

Local outside temperature in the shade 25.2C

Inside the warm room 32.1C

Inside the scope room 37.4C

Just goes to show that all that styrene insulation in the warm room helps keep it cooler in summer and warmer in winter... although 32C is still too hot to work in, but as soon as it was opened and air began circulating the temperatures started to fall quite quickly.

[malc-c]

Luke, looking at your graphs, is your weather station temp sensor in the shade - looked like it peaked at over 31c yesterday afternoon - didn't think it got that hot- we peaked at 25.6 here in Stevenage yesterday

[teleskopjo]

Interesting post,

but,

record what happens after sunset,

whether it's the warm room or the scope room which reaches outside temperature first.

Would be interesting to know!

Just checked at 13:30 BST

Observatory had been shut up all day (I've popped home from work for lunch)

Local outside temperature in the shade 25.2C

Inside the warm room 32.1C

Inside the scope room 37.4C

Just goes to show that all that styrene insulation in the warm room helps keep it cooler in summer and warmer in winter... although 32C is still too hot to work in, but as soon as it was opened and air began circulating the temperatures started to fall quite quickly.

[Polar Bear]

33C but I can get it down to 29C with the fan.

Problem is, my shed is my workshop for my business so I am working in it ! Great fun today hand sanding my bass guitar bodies

[lukebl]

Luke, looking at your graphs, is your weather station temp sensor in the shade - looked like it peaked at over 31c yesterday afternoon - didn't think it got that hot- we peaked at 25.6 here in Stevenage yesterday

Ha ha. It's in the sun. Unavoidable, really, as it's on a pole and needs to be in an open area so that the anemometer works. Unfortunately, it means that when the sun's out you get hoplessly inflated and incorrect temperature readings. Mind you, I haven't looked at seeing if I can move the temp sensor away from the main unit into a shady area.

[rfdesigner]

Ha ha. It's in the sun. Unavoidable, really, as it's on a pole and needs to be in an open area so that the anemometer works. Unfortunately, it means that when the sun's out you get hoplessly inflated and incorrect temperature readings. Mind you, I haven't looked at seeing if I can move the temp sensor away from the main unit into a shady area.

You would get most of the benefit by just adding a tiny sun shield directly in front of the temperature sensor.

I don't know how embedded the sensor is in the rest of the unit, but getting into free air on it's own in a tiny bit of shade ought to be sufficient.

[pritc]

Today

Outside temp : 27.3

Obs Temp : 27.6

Warm Room temp : 31.2

Gotta love insulation!! Great in the winter,not so much in the summer...

Wayne

[Macavity]

Yes, my little "weather station" is said to benefit from a little Aluminium foil here and there! There is a whole "science" (support group!) devoted to such things. At the moment, I've managed to find at least TWO sensors that agree on most things. LOL. Dunno about the "outside humidity" still... But the weather predictions (based on "relative" pressure?) are surprisingly good.

Comforting to know my observatory may not be bottom of the league in terms of heat trapping. Mind you, I took an hour off working in it and promptly got both forearms burnt while "taking tea" with my neighbours... Serves me right, I know!

[teleskopjo]

This is what I was referring to in message 10.

An insulated room will stay warmer during the night...

So build as light as possible. And that means no insulation.

Today

Outside temp : 27.3

Obs Temp : 27.6

Warm Room temp : 31.2

Gotta love insulation!! Great in the winter,not so much in the summer...

Wayne

[lukebl]

....I don't know how embedded the sensor is in the rest of the unit, but getting into free air on it's own in a tiny bit of shade ought to be sufficient.

Sorted! Just managed to separate the temperature sensor and move it to a shady area behind the obs. Fortunately the cables were long enough for the job.

[nmoushon]

Insulation works just as well for winter as it does summer. It works to keep the temperature from changing(obviously). But insulation is only good in the summer if you got AC in your shed/obs. But if you don't then ya it will become a sauna. One way to help with the heat gain inside is to put some form of vent in the roof or as high up as you can get it since heat rises. Its like cracking a window in your car. It won't make it cozy in there but it will help bring it down some.

[Bizibilder]

Today: 24° outside and 30°C inside at 4pm. Sunny all day.

[Gina]

Outside shade temperature here reached 25.6C. That's in a home made Stevenson screen. Sometime I must add a temperature sensor for my obsy in my weather station setup. I have several things to sort out on that. AP seems to have taken over my life!

[samtheeagle]

Great info bizibilder I was thinking about this today given how toasty it is out, and because my yardmaster is winging it's way to me now... I was toying with a simple inner skin inside the obsy, tacked on to the wooden frame, with some of that thin foam sheet insulation that has a reflective silver side to it. Not sure how much it would help? But my thinking is that it would keep things cooler during the summer, and help partition off any dewing in the colder months.

[Bizibilder]

Sam, your obsy thread was the inspiration for this one! I was having a poke around and couldn't find any real info on just how hot/cold our various "sheds" actually get - lets hope this one gathers enough data for a few "guidelines" to develop to help us all.

It would be good to compare Wood/Metal and with/without insulation etc. using some real numbers.

[malc-c]

This is what I was referring to in message 10.

An insulated room will stay warmer during the night...

So build as light as possible. And that means no insulation.

So why call it a warm room then

OK, its 11:50 bst - Warm room is 21.5c, but then there are two 24" monitors, 5A psu and a PC running, plus my body heat. The doors on the warm room are closed.

Scope room, roof rolled back, but drop side in the upright position. 15.2C, which is the same temperature as reported by my weatehr station for the current air temperature

Having 50mm thick insulation in the floor and 30mm in walls and roof of the warm room, including the dividing wall works - it stops the warmth in the warm room getting through to the scope room.

Likewise if doing solar observing, it helps keep the warm room cooler on a hot day, which is wat you need.

[jimmyjamjoejoe]

Are there any long term ill effects from storing a scope in such high temps? Will it effect coatings etc?

I keep my scope in my car at the moment (moving into a roomier place soon), and feeling how hot it got today got me a tad worried. I can deal with long cooling times etc, so long as i'm not actually damaging the scope. It gets pretty darn hot in a locked car on days like these...

[samtheeagle]

Sam, your obsy thread was the inspiration for this one!

Oooooh I feel special! An inspiration eh?