Heating and ventilation with air circulation
Under floor heating (SOFT HEAT)

This information concerns: Small houses and villas with RESARO elements placed directly on ground, Installation elements

This publication holds the following headings

Some technical facts
Suspended structural floor element with opportunity for installations
Flooring materials
Flooring in upper floor

Living during cold winters
Reference objects

The Resaro system heating system
Cleaning of ventilation supply air with Dynamic fresh air intake
Cleaning of circulation supply air

Electrical installations
Electrical installations on the top floor
The house in the future
New technical developments

At the bottom of the page
Text appendixes

Some technical facts!
The RESARO SYSTEM is a construction design aimed at 1-storey, 1 1/2-storey or 2-storey houses.
The RESARO ELEMENT can also be applied on its own, as a foundation system, to houses built in various materials such as wood, brick and concrete. Using the all concrete RESARO ELEMENT in the bottom floor.

When the exterior walls are dressed with timber paneling the space between these two surfaces is used to preheat supply air and thus complementing the heat from the solar heat collectors.

A complement to solar collectors. The space under the roofing will always be used.
When the RESARO ELEMENT is used in floor construction, then circulated air will pass freely under all floor space. This means that the floor can be evenly heated by the warmed air from the solar heat collectors.

Combining the ventilation air with the heating air system ensures an efficient ventilation system.
A moisture proof construction is used for the basement with warm ventilated basement and ground insulation as well as radon tight with a barrier of gas tight welded plastic sheeting

The basement is constructed moisture safe with warm ventilated basement and ground insulation as well as radon tight with a sealing barrier of gas tight welded plastic sheeting. !

An optional system with RESARO floor structure, for both bottom and intermediate floors, is available, facilitating under floor heating also to the intermediate floor.

The structural top floor can also be used for air conditioning, viz. Cooled air can cool primarily the top floor and there after the rest of the house.

The house can also be provided with exterior walls constructed in concrete with exterior thermal insulation. And with optional facing or surface coating.

Intermediate structural floor with space for installation.
Tests performed at the Royal Institute of Technology in Stockholm indicate that the overall concrete elements can be used for spans up to 8 m, even longer in heavier construction. The floor is firmer than a timber floor.

    • The design of the structural floor units simplifies installation and thus results in a lower price.

    • All installations are entirely accessible for inspection and maintenance as well as additions in the future.

Flooring materials
Today there are many economically acceptable alternatives for flooring available and we can choose between both synthetic and natural materials which can be installed on a cleavage layer of cork backed underlay felt or similar material.
These materials give us comfortable floors.

Also a rustic flooring can be used.
The climate for natural wood in the flooring is much better at low temperature system as the Resaro system than with common hot pipe floor heating systems.

Intermediate floor structure:
The intermediate floor can optionally be constructed with an all concrete floor structural which is somewhat more expensive than a conventional floor. The elements are turned in the intermediate floor so that the concrete slab will face downwards and thus constitute the ceiling.

The floor, which may consist of optional material, in the case of an overall concrete floor, will be laid as a floating floor on sound attenuating rubber strips on the structural floor beams.

The elements can also be turned with the slab facing upwards and with a ceiling of gypsum plasterboard, for example.

    • These arrangements provide an improved indoor sound climate between the floors when compared with conventional villas.

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Living during cold winters
We are sure you will remember the extremely cold winter of 1986. (In Sweden)
The winter of 1994 and 1996 also afforded surprisingly cold spells.
By using the RESARO heating and ventilating system you obtain:

    • a comfortable floor which warmer gets the colder it is outside, producing even temperatures over the entire area.


    • hot zones because of the intensive heat from the piping in a water borne under floor heating system (usually 28 oC to 45 oC )

    • exposed water piping that may freeze during long term power failures,

    • risk of water leaks,

    • risk of oxygen infiltration through the walls of plastic tubing into the recirculating water system, (oxygen causes corrosion in the boiler)

    • trouble making thermostatic valves for temperature control.

The building elements have been type tested at the Royal Institute of Technology in Stockholm in the Department of Steel Construction under the guidance of Professor Torsten Höglund

Reference objects:
Four semi-detached hillside houses (eight dwellings) are erected in Bollstanas, Upplands Vasby, Stockholm with RESARO elements in both floors and RESARO wall elements i ground floor.

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THE RESARO SYSTEM heating system
New comfort everywhere in the house.
Filtered indoor air mixed with fresh air for ventilation transfers into the structural floor under the floor slab.

    • The ventilating air distributes efficient to every part of the house.

    • The house is heated by the under floor heating as well as heating by the circulating air moving through the dwelling.

    • The air will enter soundlessly along the exterior walls and circulate without any draught.

    • Air circulation gives an even temperature and ventilates everywhere in the dwelling.

    • Keeps the subsoil dry at the same time as the house is heated from below.

    • The heating is allowed to spread in the natural way by means of natural air movement. This is one of the great advantages of our systems.

Noise caused by air (hissing sound) from a fan is very easy to remedy. This is accomplished with simple duct silencer. These are always included in our installations.
To keep the sound level down the support duct is always spacious in order to lower the air speed.

THE RESARO SYSTEM with Dynamic air intake
You may perhaps select the ventilation system with dynamic air intake through the roof insulation. This may consist of mineral wool or cellulose fibers. Air is sucked through the insulation by the vacuum created by the exhaust fan.

During the cold season, when it passes the roof insulation, the outdoor supply air is preheated by the heat transmitted outwards through the fibers of the insulation. Thus heat is recovered instead of lost to the outside air through the roof.

During the summer it is possible to collect outdoor air through a duct from the northern side, unless we do not want to open the windows and thus end the vacuum in the house.

    • This design gives your house outstanding thermal insulation properties despite a quite common thickness of the insulation.

    • In combination with the RESARO SYSTEM, which provides under floor heating and exhaust air ventilated foundations, no heat recovery unit is needed,

    • which results in even lower construction costs, to your benefit

    • Under floor heating and thus a decreased room temperature will give you even lower housing costs.

Cleaning of ventilation air at dynamic air intake
The roof insulation is used as a gigantic filter and cleans the air sucked threw it. The insulation may consist of fibers and functions as a filter for all particles and need never be replaced - Its capacity lasts for over 200 years ahead and lasts the entire life span of the house. Tests at among others in the Dept. of Building Physics. Lund University proves that.
The fresh ventilation supply air distributes to the entire house.

Cleaning of ventilation air
Filtering will take place in several stages.
A common double pre-filter for the entire house. The filter consists of two parts which facilitates cleaning and replacement.

    • A roughing filter that is washable, can be rinsed in the shower. This costs no money. Saves the fine filters. En filter guard indicates when it is time.

    • And a fine filter of high capacity, replacement once a year or every second year depending of the fineness of the filter desired.

    • Several houses in Sweden furnished with dynamic air intake is occupied by allergic persons.

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Electrical installations:
Electrical wiring and distribution boards are installed inside the structural Resaro elements.
Cooker, oven, freezer, refrigerator, washing machine, hot water heater, immersed heater, etc. are provided with cables with a new type of plug according to a system that ENSTO OY has developed.

    • These units are connected directly to the electrical distribution board by letting the cable down into the elements through an opening behind the skirtings at outer walls. Suspended by threading it through the web of the elements and connected to sockets in the distribution board. The electrician does not need to fasten any flexible cords by means of screws.

    • Sockets for table lamps etc. are suspended in the skirtings and are easy to move.

    • Simple to complete with new sockets when new when necessary. Fixed sockets have a tendency to be placed in the wrong place.

    • With dismounting flooring as for example the Alloc flooring it is easy to lift up the floor boarding along the walls if better accessibility is desired. For large engagement, water damage, rebuilding for new house owners etc., the entire flooring will be lifted off.

Electrical installations on the top floor
Electrical wiring for the top floor as well as ceiling lights for the ground floor are installed in the intermediate floor if this is constructed of concrete elements without need for cutting of holes to get past any beams.

    • Dismounting flooring enables accessibility in the future even in this part of the house.

If RESARO elements are not used, wiring for the top floor will be installed in a conventional way.

The house in the future

A house must be operable for several generations. Supplementary purchases of appliances are usually necessary after 10 or 15 years.

    • Should not a house planning concept be such that it will not prove to expensive to change appliances in the building?

    • Should this not be easy to perform, for example with plug-in connections for power, water and sewage discharge.
    For repairs to traditional houses more than 50 years old, it is today cheaper to demolish than reconstruct due to the fact that everything is so inaccessible.
    • With the new thinking of today regarding recovery and recycling it is natural to develop a system that tasks consideration to the above.

New technical developments
But even new technology is continually being developed.
The house is easy to modify and complete in that case other new components are concerned,
Who knows today what we might want to install in ten years time.

If you chose the RESARO SYSTEM it is much more probable that it will be possible to carry out changes to your house because of the excellent accessibility.

    • The trade-in value of your house is increased.

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Short information about the "Dynamic fresh air intake"