Energy conservation v tight building syndrome

[deek]

It appears to be politically correct in today's environmentally conscious world to build housing that conserves heat energy (minimal heat losses) and add draught proofing to existing housing. In other words create "tight buildings".

My question is; at what cost? It is widely recognised that making buildings air tight causes wide ranging health complaints including allergy type symptoms (chemical sensitivity) in building occupants where the ventilation rates are substantially reduced. These symptoms have given rise to the term used by practitioners in occupational health; tight building syndrome.

All internal fixtures, fittings and furniture including wall and floor coverings emit high levels of VOCs (volatile organic compounds) when new and these indoor pollutants are recognised as causal factors in tight building syndrome. The off-gassing may last for years (yeah that's correct, years) and the VOC off-gassing is accelerated when the indoor air is heated.

Whilst research has identified the numerous VOCs emitted from building fixtures, fittings & furniture and the types of materials that cause the highest emission rates, very little has been done to address these serious health concerns.

So what advice would I give;- I would strongly recommend opening your windows (but don't compromise security) and allow fresh air to freely circulate around your home whenever possible.

[screener]

Opening the windows and letting in some fresh air is a good suggestion, and this has been a concern for quite a while. One option is to put an air to air heat exchanger in a closet by the outside wall. You bring fresh air into the house via the heat exchanger and stale inside air exits. It's basically a radiator that allows the incomng air to absorb the heat from the outgoing. There is water condensed out of the cooling air going out so that has to be caught and managed. The dry incoming air then goes to the furnace if you have one or is cycled through a fan if you don't or if you're not in a heating season.

[Besoeker]

Apart from any other consideration, if a building were completely tight wouldn't human occupants use up the available oxygen and eventually suffocate?

[screener]

well the other thing that helps is if you have the hanging gardens in the building.

[spadlet]

I think that the theory is supposed to be having cotrollable ventilation, not non-existent ventilation. Calculations exist to calculate the number of air changes that should occur in a room based on size and usage. Ventilation can then be adjusted to optimise this whilst minimising heat loss.

Another option is to make an airtight building with a ventilation system connected to a heat exchanger. The ventilation system needn't be as energy intensive as conventional air conditioning. An example of such a system seems to work well at Hockerton Housing Project.

Buildings in which there is no air flow are bad. They allow moisture to build up, encouraging damp problems which at worst could lead to dry rot. These days, for example, all double glazing should have trickle vents.

[Besoeker]

Originally Posted by spadlet

Another option is to make an airtight building with a ventilation system connected to a heat exchanger.

But, if it is airtight, there would be no new air.
You'd need to make provision for the introduction of oxygen and the removal of CO2.
Or just not make it airtight.

[screener]

Air tight with ventilation rather than leakage, stop leaks because they are drafty, bring in heat exchanged air, oxygen levels are maintained, heating bills are lessened, pocketbook feels heavier. bonus.

[Besoeker]

Originally Posted by screener

Air tight with ventilation rather than leakage, stop leaks because they are drafty, bring in heat exchanged air, oxygen levels are maintained, heating bills are lessened, pocketbook feels heavier. bonus.

Yes, I see that.
It would work for cooling as well.

[Wobs]

Originally Posted by screener

Air tight with ventilation rather than leakage, stop leaks because they are drafty, bring in heat exchanged air, oxygen levels are maintained, heating bills are lessened, pocketbook feels heavier. bonus.

There's a fine line between what is considered a draft and what is considered ventilation in most houses. Heat recovery from heat escaping is available for things like loft areas, and triple glazing can be used to heat incoming air:
Air Flow Windows
Air Flow Windows

There have been studies on them, but don't know of the results off hand.

Normal double glazing people will tell you that there windows are draft proof, but then go on to tell you that they have trickle vents (well they need them). Like I say, ventilation/ draft - there's a fine line.

[screener]

The vent window looks like a really simple alternative to a heat exchanger. I would say that if you heat with electricity, Ie no flue, no exhaust air then there is no draw for the windows. If you are heating with a furnace or heater having a flue and the heater is off then the air flow could go the other way unless there is a flap of sorts to prevent that. For example at night the warm air inside at the level of the top of the window would be pulled into the area between the window segments as the air there cools and drops outside.