HOW DOES DYNAMIC FRECH
AIR INTAKE FUNCTION?
Heat exchanger effect
When air is drawn by suction into the building interior through
the layer of heat-insulating material at a very low rate of flow,
an exchange of heat takes place.
Calculations performed at the Royal Institute of Technology in
Stockholm indicate that the increase in temperature of the incoming
air can be compared with a corresponding increase in a heat exchanger
for recovery by an efficiency rate of 15 percent.
Please compare with a big heat exchanger which change
energy between outward passing exhaust air and inward passing
This can give a maximum temperature efficiency of ca 45 %, but
it is expensive and must be cleaned once a year. Our arrangement
gives us 15% without extra costs.
- Nature always strive for temperature balance.
As cold outdoor air passes through the insulation on its way
into the building in the cold period of the year, it cools down
the thermal-energy carrying insulation fibres, wherewith the
outdoor air is heated and the heat returned back into the building.
Even a thin thermal insulation layer will provide a highly effective
The pressure equalising layer provides an evenly distributed
air stream through the roof insulation.
- The roof functions as a preheater for the incoming air in
two ways: partly by the solar heating developed under the roofing
material outside the insulation and partly by the heating of
the incoming air during its passage through the insulation.
- The dynamic air intake procedure lead to a normal insulation
thickness gives en insulation capacity corresponding to more
than double the thickness.
Considerably thinner insulation layers can be used to preserve
against coldness, than what is common in other systems.
- But a summer´s day there is very hot in the attic.
The fact is the roof insulation is dimensioned to keep out the
heat at summertime.
At summer time we don´t want the heat to penetrate inside.
That is why we use cool outdoor air from a northen side at summer.
As a result of the low rate of flow, the thermal insulating layer
will also engender an effective filtering effect, such that the
through-passing air will be practically particle-free.
- Investigations at Dept. of Building Physics. Lund University
shows that practically no particles from outside or from the
insulation joins the outdoor air into the house.
Please look at the report "Optimät - a concept for
energy efficient and healthy single family houses based on dynamic
insulation technique, Arne Elmroth, Bertil Fredlund and others,
Lund University, Box 118, S-22100 LUND"
(The house in the report was furnished with loose wool of glass
- Because the air is sucked in through a large thermal insulation
area, loading of the thermal insulation with particles separated
from the air sucked through the insulation will be negligible
in light of the practical life span of the building.
- The term of life of the "Filter" has been calculated
to at least 200 years.
More about Dynamic fresh air intake, please look at the reference
to "the solution for several of serious building problems
of today", below.
142 31 Skogas
Phone +468 5413 7800,
Information about the RESARO system for small houses
Short information about the
"Dynamic fresh air intake"
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