airconditioning

[Anonymous]

Hello,
I may be asking the wrong person, but, I live in a 1920 house which has lathe ceilings through out.
The house is fine until it warms up and then, it gets hot and stays hot for several days, even after it has cooled down. Each year I consider airconditioning.
My questions are - does evap aircond damage the plaster throughout a house of this age? If I put ducted air cond into the lathe ceilings, when they cut the plaster to insert the duct, do I risk damaging them?
Any advice you are able to give me would be very much appreciated.

Thank you.
Treena Lewis

 

[Anonymous]

Unless there is a medical condition to be considered I cannot think of any reason why you should need A/C in this country in a 1920,s house.

It is your house and you can do pretty well anything to it , done correctly it should not cause much damage. The only damage you will cause, is to your pocket and most important to the enviroment. ( and your health)

Surely this " heat" is not a problem in the spring, autumn and winter months, the summers usually last a week if we are lucky . On these " odd" days a cheap ventilation fan and good air flow should be adequate.

 

[Anonymous]

>does evap aircond damage the plaster throughout a house of this age?

Evaporative/swamp coolers work by blowing air through a saturated pad, evaporating water. The water absorbs heat ( latent heat of vapourization) from the air, so the air temperature drops.

Although the air temperature drops, the air relative humidity increases. The human cooling system, perspiration, also works by evaporative cooling, so it's then less effective. The end result is that you feel clammy and more uncomfortable. Evaporative coolers work OK in a hot dry climate; they're a complete waste of time in the UK, IMHO, and are only bought by those who don't understand relative humidity. They sell them cheap on E-Bay when they've learnt.

Probably wouldn't damage the plaster, but it depends on how damp the air becomes and where the water vapour condenses. Don't bother.

> If I put ducted air cond into the lathe ceilings,
>when they cut the plaster to insert the duct, do I
>risk damaging them?

Probably, depends on how weary the plaster is. If you need AC, go for a refrigerant split system (outside compressor/condensor) or don't bother. You could also get heat pump models, which might be useful if you're not on mains gas.

The heat gains into the house suggest very high solar gains; either there's a lot of south-facing glazing &/or the thermal insulation could be improved.

 

[Anonymous]

This was touched on by Aidan - have you considered improving the the thermal insulation properties of your house? IMO this would be a much more cost-effective way of approaching your problem. Air con is going to cost you a fair bit of money (to little effect - read Aidan's explanation) and will only be used a few days/weeks of the year. Better thermal insulation would keep your house cooler in summer - plus it would keep it warmer in winter and save your heating bills. In the UK we use heating vastly more than we do cooling, so this has to be a win-win idea.
Spend your money on thermal insulation!

 

[Anonymous]

During the hottest times, forced ventilation at night steadily reduces a house fabric's temp, so it starts from a lower temp in the morning. This is an energy efficient minimal cost way to cool a place. Switching one of these on in the evening at the previous house gave typical 6C drop, upto 10C drop. Those are 30 minute figures, not figs for how much cooler it was during the day.

Putting deciduous climbers on the south facing wall can keep a lot of heat off the house too. Also check your loft insulation, hot sun on a dark roof produces a huge amount of heat.

NT