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My wife is a teacher in a new school that has just been built in the North East UK, and staff and pupils think it's too warm. They have been told that:

"new buildings are warmer due to the curing / drying of the materials for the first few years".

This sounds like bunkum to me. Can anyone deny or confirm this?

ChrisF
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PaulHurleyuk
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    I think if anything, new buildings would be warmer because their heating systems are brand new and efficient. – shufler Mar 27 '12 at 21:05
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    Maybe the folks at http://skeptics.stackexchange.com could dig up some answers. – auujay Mar 27 '12 at 21:46
  • The only reasonable explanation I can think of is that humid air feels warmer, so while the cement and other materials are drying/curing, they are evaporating water and increasing the relative humidity. – Steven Mar 27 '12 at 22:35
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    Concrete does "cure" with an exothermic reaction over time (as the dehydrated mineral compounds of the cement form a crystalline structure using the water, forming hydrates). However, the amount of heat that even a commercial building slab gives off as it dries is negligible compared to a good furnace. Similarly, the amount of water that leaves concrete between when it's "dry" and when it's "cured" is miniscule compared to the average amount of water in the air at any given time. Unless you're in Arizona, where 20% RH is muggy, you wouldn't notice a difference. – KeithS Mar 28 '12 at 00:05
  • The curing process of Plaster is also an exothermic reaction, and can create enough heat to burn your skin. – Tester101 Mar 28 '12 at 17:15
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    @Tester101, even if you assume curing plaster is putting off heat, the thermostat should automatically adjust how much heat is generated by the furnace to compensate. – BMitch Mar 29 '12 at 01:10
  • @BMitch true, but a furnace wouldn't remove excess heat. And poor thermostat placement could contribute to the problem. – Tester101 Mar 29 '12 at 10:45

4 Answers4

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One must ask how it is that the thermostats know they are installed in a building with materials that are still curing and drying? They don't. 18°C on a thermostat is the same regardless of a building's age. The students may be noticing that the new building is less drafty than the old. A lack of drafts will make a room seem warmer than a similarly heated, but drafty room.

Wayfaring Stranger
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Urban myth. Totally untrue. Heard it before, don't believe a word of it.

shirlock homes
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  • Couldn't older schools were the windows and doors fit looser create more drafts? With more air moving around it would give the impression of a cooler room, but the temperature would be the same. Sort of like a ceiling fan doesn't really lower the temperature, it just stirs the air and keeps you cooler. I would think its the same but on a way much smaller scale. – lqlarry Mar 28 '12 at 00:33
  • I guess drafts could make it feel cooler, but buildings of recent quality construction, say less than 10 or 15 years old shouldn't have tremendous issues with loose windows, doors and drafts. Sorry, I still don't buy into the myth. – shirlock homes Mar 28 '12 at 11:27
  • Plaster creates heat when it cures. Is it possible this could have been true at some point? Though I guess by the time people are using the building, the plaster would already be cured. – Tester101 Mar 28 '12 at 17:12
  • @Tester101: If plaster or concrete took that long to cure, no one would use it. – Engineer2021 Apr 19 '12 at 12:49
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I have worked in 14 new schools in the last six years they are all built under the U.K governments PFI initiative. (http://en.wikipedia.org/wiki/Private_finance_initiative) They are responsible for hundreds of new schools across the country. I can honestly say in every single one the temperature is set too high. Yet most of these schools are maintained by a Facilities Management companies and they specify under guidelines of where the thermostats should be set. Most people agree they are too hot. Alot of them use underfloor heating which is sunk into a type of concrete slurry under the floor. they seem to be very hard to regulate at a constant temperature as they take a while for the heat to radiate.

Ryan Walkowski
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Another factor is that new buildings will be better insulated and more airtight. Less heat/cold will mingle with outside air. This, combined with newer and more efficient heating/air conditioning units (with greater capacity too), would probably explain any extreme temperatures.

Even if the thermostat is set to the same temperature, the building as a whole will probably retain more heat and have it more uniformly distributed (as opposed to being cooler/drafty by the windows etc).

The Other Steven
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