GENERAL INFORMATION RENOVATION PROCESS RETROFIT SOLUTIONS EVALUATION

Platzbon

Rutzenberg 41

39042

Brixen, Italy

Architect

Dr. Ing. Benno Graus

Rienzdamm 14, 39042 Brixen

ing.graus@gmx.net

+39 0472 835374

Owner

Fam. Markus Oberrauch

Rutzenberg 41, I-39042 Brixen

info@platzbon.it

39 334 18 40 958

Contact Details

Alexandra Troi

Hochschule Coburg

alexandra.troi@hs-coburg.de

Other Information

Visits
Use as residential house and holiday apartments - www.platzbon.it

Related publications
http://itaspreis.gruppoitas.it/die-gewinner-2017/

Platzbon über St. Andrä bei Brixen (©Leonore Schmidt) - www.platzbon.it

The mountain farm is located above St. Andrä, with a wide view over the Eisack valley. There are only meadows and woods all around, no traffic noise disturbs the peace and quiet. The old farmhouse has been renovated with loving attention to detail, while at the same time paying attention to a biological construction method and the use of regional materials.

GENERAL INFORMATION RENOVATION PROCESS RETROFIT SOLUTIONS EVALUATION

Energy performance

74 kWh/m2.y

Climate Zone F

Altitude 1330 m a.s.l.

HDD 3214

CDD 0

Protection level Not listed

Conservation Area:
No

Level of Protection:

Building age before 1600

Year of last renovation:
2016

Year of previous renovation:
1970

Building use Residential (rural)

Secondary use:
Agricultural & Fishery

Building occupancy:
Permanently occupied

Number of occupants/users:
4

Building area Net floor area [m²]: 369,0

Building typology:
Tenement (apartments)

Number of floors:
3

Basement yes/no:
Yes

Number of heated floors:
3

Gross floor area [m²]:
435,0

Thermal envelope area [m²]:
699,0

Volume [m³]:
1196,5

NFA calculation method:
NGF (de)

Construction type

Stone masonry wall

External finish:
Rendered

Internal finish:
Exposed woodwork

Roof type:
Pitched roof

+ MORE - LESS

Only meadows and woods all around(©Leonore Schmidt)

Numrous details were preserved (©Leonore Schmidt)

Entrance door, before retrofit (©Leonore Schmidt)

West view, before retrofit (©Leonore Schmidt)

RENOVATION PROCESS

Architecture

BUILDING DESCRIPTION

The organic farm "Platzbon" is located on the Plose at 1330 m above sea level. The farm is isolated and quietly situated, surrounded by meadows and woods, with a view over Bressanone and the Eisack Valley. The simple farmhouse with its crippled hipped roof is enthroned in the middle of a wonderful alpine landscape. After the restoration work, the building will house a private apartment of the farmer's family on the ground floor and two holiday apartments on the upper floor. The attic offers space for guests of the family. During the renovation, great importance was attached to the use of only natural and regional materials. The massive, plastered walls are made of the regional Brixen quartz phyllite, which is partially exposed in the interior. For the reconstruction of the roof in its original form, pine and spruce wood was used, while the ceiling construction is made of larch wood. The walls in the interior are plastered or panelled, and the above-mentioned regional quarry stone is also used for both the wall and floor design. Working with natural materials was an essential part of the cooperation between the architect and the client. During the implementation the builders did a lot of work on their own.

Urban context

The farm is mainly surrounded by coniferous forest and mountain landscape and is accessed via an driveway. The nearest village St. Andrä is 2.5 km away on foot. The nearest town Brixen can be reached by car in 20 minutes.

State of repair

Conditions of the envelope

It was very important to the owners to preserve the historic farmhouse as well as possible, but the existing building had neither insulation nor heating. The house also had no foundation, so the quarry stone walls were on the ground. In the former kitchen on the ground floor e.g. the slabs were lying directly on the soil. Under the concrete plaster applied in the 1960s, the substructure of the living room stove, as well as the new and the old pass-through became visible. The ceilings had different build-ups.Mainly there were wooden beam ceilings which were filled with Heraklith in between, while in the new kitchen the ceiling consisted of wooden beams and straw-lime filling. Mainly there were wooden beam ceilings which were filled with Heraklith in between, while in the new kitchen the ceiling of the room consisted of wooden beams and straw-lime filling. Here a walled up balcony door became visible and the floor construction of wood between ground floor and cellar. On the upper floor, to separate the rooms, there was a wooden construction built in the 1840s and filled with white-green painted, hand-planed Swiss stone pine panels. In the 1960s these were clad with polystyrene and wood panels. The beam construction also supported the roof ridge. In the false ceiling, however, there were only ceiling beams and floor boards. Three of the exterior walls on the upper floor were replaced by brick walls in the 1960s, thus underpinning and elevating the existing roof truss. Translated with www.DeepL.com/Translator (free version)

Description of pre-intervention building services

Before the renovation there were only cold water supplies in the kitchen and in the bathrooms. No heating system except the tiled stove in the parlour.

HERITAGE SIGNIFICANCE

ELEMENTS WORTHY OF PRESERVATION

The foundation walls on the ground floor made of quarry stone have been almost completely preserved. The window and door lintels as well as the Gothic door leaves were also worth preserving. Further elements that were protected are the ceiling beams with straw-lime filling in the kitchen area, as well as the stone floor in the kitchen, "Labe" (typical entrance hall) and guest toilet. In addition, the wooden panelling of the parlour and the bedroom, as well as the historic oven in the parlour were preserved and restored.

Heritage Value Assesment

The building is not a listed building, but the owners have taken care during the renovation work to preserve the original character of the farm. As the house is not listed and therefore subject to the obligation of energy-efficient renovation, the old plaster had to be removed and replaced by an insulating plaster

Aim of retrofit

Renovation

The aim of the refurbishment was, on the one hand, to improve the building's energy efficiency. With the help of Röfix insulating plaster, the renewal of the roof and the replacement of the old single-glazed windows with triple-glazed insulated windows, this goal was achieved. Moreover, it was a concern to adapt the building to today's standards by installing a heating system. On the other hand, an extension of use was made possible due to the planning of two holiday apartments on the upper floor. These can be connected with the private apartment by a staircase breakthrough when the family grows. Although almost every generation has worked on the house and changed something of the "original", it was important to the owners to retain the basic character and flair of the farmhouse. They did not want a "mixture" of tradition and modernity in the sense that the whole thing would end up looking like a new building or being irrevocably combined with modern elements. It was important to them to leave the crooked walls and inclined angles visible. New building elements such as the external staircase were to remain "in style", and were built "gently" without major intervention. Because this house is to be preserved for future generations, the renovation should not affect the space and room requirements of future residents. The house should not be "obstructed" in the eyes of the following generation, but should remain adaptable to the changing space requirements through the simplest of measures. Ground floor and holiday apartments can be reconnected in any combination at any time. The main focus of all renovation phases was to preserve the character of the farmhouse by using natural, high-quality and regional materials.

Was there any change of use?

Before the renovation, the farm was used exclusively for agricultural and residential purposes. Now, in addition to the private apartment on the ground floor, there are two additional residential units that are rented out as holiday apartments (www.platzbon.it). The agricultural use has not been lost.

Lessons learned

Since the clients have taken over the majority of the work themselves, they can now benefit from a great deal of experience in dealing with an existing historical building. Above all, it is important to plan the construction process in order to avoid complications. When demolishing the ground, for example, care should be taken to ensure that the transport route for the materials is not restricted. When underpinning the cellar walls, care must be taken not to remove too much earth, otherwise there is a risk of collapse. The wall halves should always be excavated, formed and concreted individually. There were also weather-related difficulties with the roof extension, the reason for this was the stone walls on the upper floor, as they were not allowed to get wet. During the renovation, it was also shown that it is possible to renovate the existing building to a high standard even with a lot of work on one's own.

Stakeholders Involvement

Private Sector
Fam. Markus Oberrauch
Rutzenberg 41, 39042 Brixen
info@platzbon.it
Tel. 39 334 18 40 958

Architect
Dr. Ing. Benno Graus
Rienzdamm 14, 39042 Brixen
ing.graus@gmx.net
Tel.+39 0472 835374

Energy Consultant
Klimahaus Energieberater - Geom. Thomas Graus
Am Hohen Feld 6, 39042 Brixen (BZ)
thomas.graus@gmail.com
Tel.+39 347 7448812

Structural Engineer
Dr. Ing. Benno Graus
Rienzdamm 14, 39042 Brixen
ing.graus@gmx.net
Tel.+39 0472 835374

Tools used

Was the renovation process done following a specific methodology? No

Energy calculation KlimaHaus-Berechnung

ITAS award - Statement of the Jury ITAS award - video (german) Retrofit summary (German, ©Böll/Schwarz) Come and visit PlatzBon!

RETROFIT SOLUTIONS

External Walls

Ground floor

Upper floor

Ground floor

The 70cm thick, repaired existing wall of quarry stones was provided with a 12cm thick layer of lime-based insulating plaster. Röfix CalceClima Thermo (with a lambda value of 0.067 W/mK)and CalceClima Fino were used for the exterior plaster. For the interior plaster, Röfix CalceClima Ambiente and Röfix Smooth Lime were chosen. With these building measures, Climate House Standard B was achieved.

The existing walls on the ground floor were only insulated on the outside, as they were worth preserving on the one hand, and on the other hand, parts of the interior should be visible. This becomes clear from the exposed window lintels.

U-value (pre-intervention) [W/m2K]: 2,22 W/m²K U-value (post-intervention) [W/m2K]: 0,44 W/m²K

More Details

Original wall build-up

Plaster - Kalkgipsputz:
20 mm

Stone - Quarzphyllit:
700 mm

Plaster - Kalkgipsputz:
20 mm

Retrofitted wall build-up

Plaster - Röfix CalceClima Ambiente und Röfix Kalkglätte:
20mm

Stone - Quarzphyllit:
700 mm

Insulation - Röfix CalceClima Thermo :
120 mm

Plaster - Röfix CalceClima Fino:
20 mm

Upper floor

On the upper floor a complete demolition of the walls, renovated in the late 1960s, took place. Only the quarry stone wall on the uphill side was preserved. The walls were rebuilt with "insulating bricks" (Unipor W08 Plan bricks, 0.08 W/mK), which allowed to increase the thermal performance considerably.

This was possible, since the walls from the 1960s were not considered worth preserving.

Nordansicht Baustelle (©Leonore Schmidt)

Abbruch der Bestandsmauern (©Leonore Schmidt)

U-value (pre-intervention) [W/m2K]: 1,25 W/m²K U-value (post-intervention) [W/m2K]: 0,18 W/m²K

More Details

Original wall build-up

Render - Kalkgipsputz:
20 mm

Brick - Lochziegel:
365 mm

Render - Kalkputz:
50 mm

Retrofitted wall build-up

Render - Röfix CalceClima Ambiente und Röfix Kalkglätte:
20mm

Brick - Unipor W08 Plan Ziegel:
425 mm

Render - Röfix CalceClima Fino:
20 mm

Windows

Three sectioned muntin window

New triple-glazed wooden sash bar windows were installed throughout the building. The insulation plaster was pulled up to the window jambs, the window jambs and blind jambs were replaced and airtightly sealed.

The heritage was taken into account mainly by the choice of material - wood - and the traditional division. The windows were completely replaced, only the lintel remained.

Existing window U-value Glass [W/m2K]: 5,5 New window U-value Glass[W/m2K]: 0,7 Existing window U-value Frame [W/m2K]: 1,06 New window U-value Frame [W/m2K]: 0,7

More Details

Existing window type	Double window
Existing glazing type	Single
Existing shading type	Moveable shading
Approximate installation year	1970

New window type	Double window
New glazing type	Triple
New shading type	Moveable shading
New window solar factor g [-]	0,55

Other interventions

ROOF

GROUND FLOOR

OTHER

ROOF

The building was partly demolished from the 1st floor onwards, renewed and the roof construction was raised to such an extent that another habitable floor was created.

However, the historical roof form was reconstructed - even if the construction from 1970 itself was not worth preserving. Actually, the roof was renovated at least 3 times in the last 150 years (1880, 1927 and 1967), but not completely, it was always just pieced up and repaired. The uninsulated roof truss would in no way have met the requirements of energy insulation, let alone the requirements of statics. During the renovation, the intermediate ceilings were also acoustically insulated (thickness approx. 50 cm), and the roof was consequently raised somewhat in order to still create sufficient living space on the upper floor.

U-value (pre-intervention) [W/m2K] 1.22 U-value (post-intervention) [W/m2K] 0.17

More Details

Original roof build-up

Tiles - dunkelgrauer Dachziegel:
70 mm

Other - Trag- und Konterlattung:
80 mm

Other - Sparren:
240 mm

Other - Holzverkleidung:
20 mm

Retrofitted roof build-up

Tiles - dunkelgrauer Dachziegel:
70 mm

Other - Trag- und Konterlattung:
80 mm

Other - DWD-Platte:
20 mm

Other - Sparrenaufdopplung mit Dämmung:
240 mm

Other - Holzverkleidung:
20 mm

Other - Sparren:
240 mm

GROUND FLOOR

The floor covering was removed, partially repaired and reinstalled. Above the basement the wooden beam ceiling was reinforced, insulated and provided with a new floor construction. The part without cellar was replaced with additional reinforcement and gravel fill. In the area of the kitchen and the bathroom an underfloor heating was installed.

During the renovation, stone slabs of Brixner quartz phyllite were rediscovered. These were reused in the kitchen and the "Labe".

U-value (pre-intervention) [W/m2K] 6,55 U-value (post-intervention) [W/m2K] 0,284

More Details

Original groundfloor build-up

Other - Erde:
1000 mm

Solum - Quarzitplatten:
50 mm

Retrofitted groundfloor build-up

Other - Erde:
785 mm

Other - Marmorsplitt und Perlite:
150 mm

Concrete slab - Betonplatte:
100 mm

Finish - Fliesen/ Quarzitplatten:
15 mm

OTHER

The parlour and the parlour chamber from 1834 as well as the old panelling of the upper floor were expertly removed, restored and reinstalled.

Since the building had been energetically improved with insulating plaster, there was also no need for coordination conservation - energy.

Stube nach der Renovierung (©Leonore Schmidt)

Stube vor der Renovierung (©Leonore Schmidt)

HVAC

HEATING

DOMESTIC HOT WATER

HEATING

Before the renovation, heating was only provided by the oven in the parlour and the stove in the kitchen. A boiler was installed, which is fired with wood chips and emits the heat mainly via radiators and partially via underfloor heating.

The historic oven in the parlour is still in operation, alongside the modern heating systems.

More Details

	New primary heating system	New secondary heating system
New system type	Heizkessel	Stove
Fuel	Biomass	Biomass
Distribuition system	Radiators	Radiating surface
Nominal power	30 kW	7 kW

DOMESTIC HOT WATER

The domestic hot water is provided by the new heating system.

This was an important step to bring the building to today's user expectations.

More Details

	New DHW system
Type	with heating system
Hot_water_tank	Yes
With heat recovery	No

RENEWABLE ENERGY SYSTEMS

Photovoltaic

Biomass

Photovoltaic

Two photovoltaic systems of 19 kWp each are installed on the roof of the nearby barn. One serves to generate electricity for the residential house and the other for agricultural use. Exchange with the electricity net takes place in both systems.

In order not to disturb the historical building apperance, the photovoltaic system was installed on the roof of the newly built barn.

More Details

	Photovoltaic System
Type	Polycrystalline
Collector area	m²
Total nominal power	38,0 kW

Biomass

The heating system is fired with wood chips. It consumes 120m³ per year - for hot water and heating for the house, but also hot water for the barn (milking machine cleaning and cattle watering).

The wood from the adjacent forests can be used, thus keeping the ecological footprint low.

The boiler and wood chip silo found a place under the entrance of the hayrick - additional soil had to be excavated for this purpose. The 2000-liter buffer storage is located in the cellar of the house and accessible via an external staircase.

More Details

	Biomass System
Type	Chips
Storage size
Origin of biomass	Holz aus anliegenden Wäldern
Overall yearly production	30,0 kWh

Energy Efficiency

Energy Performance

Energy performance certificate: With a calculated 47 kWh/m²a for Bolzano climate, the building now corresponds to Klimahaus B
Voluntary certificates: No

Energy Use

Heating
Consumption_estimation_Calculation_method: Steady state simulation (e.g. EPC, PHPP)

Documents:

2_KlimaHaus-Ausweis_2.pdf

Klimahaus certificate

Consumption_estimation_After: 74 kWh/m2.y

Primary Energy
Consumption_estimation_Calculation_method: Steady state simulation (e.g. EPC, PHPP)
Consumption_estimation_Including_DHW: Yes
Consumption_estimation_After: 39 kWh/m2.y

Internal Climate

Temperature

The interior temperature is described by the residents as comfortable. The different heating systems - underfloor heating, radiators and the parlour oven - can be used independently of each other and according to your well-being.

Indoor Air Quality

Due to the natural ventilation, the air quality is perceived as pleasant. In turn, the residents must contribute to a pleasant indoor climate by regularly airing the rooms through the windows.

Daylight

The rooms are all sufficiently lit and give a pleasant feeling.

Acoustic Comfort

The acoustics have been significantly improved by installing impact sound insulation in the ceilings and the windows are now soundproofed.

Costs

Financial Aspects

Running Costs

Lifecycle cost
No

Environment

Greenhouse Gas Emissions

Methodology_used: The method used by the Klimahaus was used to determine the CO2 emissions.

Documents: