Cooling down a Polycrub!

[Stubblemonster]

I know, sounds daft but we have had someone build a polycrub at a charity and it's waaaay too hot. With an ambient temperature of 20 degrees outside and with two extractor fans running we are seeing temperatures of 38 degrees centigrade. We are hoping that we can use some sort of IR blocking film that's usually used on glass conservatories and windows but I wondered if anyone has done this on curved polycarbonate and if it's recommended? Also, the black poly pipe that supports the structure is black and acts as a giant heat pipe when in the sun, is there any reason we couldn't vinyl wrap the pipe in white to stop this?

 

Thanks

 

Graham 

[Redbeard]

I had to look up 'polycrub' but it seems to me that you have what you have - a glazed space with no shading (?). It will get hugely hot if not shaded, and I am somewhat (very?) sceptical re what 'IR blocking film' will achieve. Shading inside is arguably too late. Can you throw sheets over the top?

24 minutes ago, Stubblemonster said:

it's waaaay too hot.

For what? What are you trying to use it for? The worst situations I have seen are where organisations have a conservatory built without quite knowing *why* they are having it built. They then try to use it as a meeting room or whatever and it is too bright, too hot, too... etc... A polytunnel seems even worse.

[JohnMo]

Soak the floor and beds with water? The evaporation will draw some heat away. But its a green house what do they expect to occur?

[twice round the block]

@Stubblemonster

Have you got openings both ends?

[Stubblemonster]

It's being used to keep some aquatic animals in, I won't be too specific but suffice to say it's too hot as is. I am not sure of the reason this building was chosen. There are doors at both ends but security means they can't be left open. 

[Jenki]

It's doing what it's designed to do. Film won't work, I've built a few, too late but if livestock were going in 

.I.e. lambing or poultry you can use Opel sheets.  Other option is to cut some windows in either end you'll definitely need cross ventilation. 

Mine is in the Highlands, 12deg outside can see mid 20's inside 

[saveasteading]

53 minutes ago, Stubblemonster said:

I am not sure of the reason this building was chosen.

because it is very cheap compared to the options.

 

the obvious solutions are ventilation and shade.

vent as much as possible. if security is an issue then build a chimney/funnel.

shade is best though. White  or reflective wrapping so that the sun gets caught or reflected away.

a wettened floor works but the damp air then needs to be ejected. 

[SteamyTea]

Get some silvered mylar (think Space Blankets) and stick them on the top sections (contact adhesive).

Then see how it goes.

 

 

[Conor]

Couple coats of whitewash. It's what my brother in law uses for his glasshouses and tunnels during the summer in his horticultural business. Rain eventually washes it off.

[Kelvin]

I’ve used a white tarp over the top of our chicken run mostly to keep it dry but it also helped control overheating of the coup inside the run. 

[Stubblemonster]

Thanks everyone for your thoughts, I do have a company sending some samples of a heat reducing film designed for twinwall conservatories but yes our other option was to create some shade, either by using some sail shades or another method. I expect cost is right, as a charity that was foremost I expect but it seems to be the wrong building for the job. Ripping it down isn't really an option so we must adapt! I'm only involved as I'm the IT guy and I put some smart temp monitors and fan controllers in to try to get the temp down but even at full tilt the fans (which are industrial grade) only drop the temp by 2 degrees. I'll report back how we get on.

[SteamyTea]

Delhi, India has recorded (unofficially) 52.9°C OAT.