The temperature in my loft

I recently (mid October) moved my home server into my loft, as its constant noise under my desk was getting on my nerves.

However I found that with a large area of roof exposed to the sun (even the weak Autumn sun), and practically no ventilation the ambient temperature fluctuates enormously.

In October when it was a little warmer and a little sunnier, the temperature would drop almost as low at 10°C and almost as high as 30°C. An ambient temperature of over 25°C seems to drive my disk temperatures up to over 50°C. This constantly changing temperature with high and low extremes is a sure-fire way to break hard disks.

After Week 42, I opened the loft trapdoor, which went a long way to keeping the temperature more constant. Unfortunately it also makes the flat rather cold.

Now it’s much colder outdoors, I’ve closed the trapdoor again and the loft temperature seems pleasantly cool and reasonably constant. Today the temperature up there is a steady 13°C, although the sun hardly shone. That’s cooler than your average air-conditioned data centre – and all free thanks to the crappy British weather 🙂

Oh, and the 6 disks are now all between 25°C and 30°C.


  • I’m measuring and graphing this using a TEMPer USB thermometer, using Nagios monitoring software with my own plugin and PNP4Nagios to draw the graphs.
  • The “outage” between weeks 43 and 44 was caused by the shift from BST to GMT, apparently. I didn’t notice for a while, but restarting Nagios fixed it 🙂

One thought on “The temperature in my loft

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: