Hof Neuhäusl

Seebach 23

6351

Scheffau am Wilden Kaiser, Austria

architetto

DI Hans Peter Gruber
Lindenstraße 2, 6020 Innsbruck
gruber@hpgruber.at
+43 512 343884

Owner

Dr. Markus J. Rieder
Schopperweg 30, 6330 Kufstein

Contact Details

DI Alexander Rieser
Universität Innsbruck
alexander.rieser@uibk.ac.at
+43 512 507-63601

Other Information

© David Schreyer
The 300-year-old "Hof Neuhäusl" is a prime example of the combination of old building stock and energy efficiency. While retaining its historical appearance, the building was refurbished completely in 2017. The preservation of the façade required the implementation of consistent interior insulation. Inside, the rooms were restructured in order to meet the highest, modern living standards. The revitalisation of the courtyard was awarded with the "Tiroler Sanierungspreis" in 2018.
Energy performance
17 kWh/m2.y

Climate Zone Dfb

Altitude 772 s.l.m.

HDD 2446

CDD 574

Protection level Not listed

Conservation Area:
No

Level of Protection:

Building age 1700-1800

Year of last renovation:
0

Building use Residential (rural)

Building occupancy:
Discontinuous occupancy (i.e. holiday home)

Number of occupants/users:
2

Building area Net floor area [m²]: 158,5

Building typology:
Detached house

Number of floors:
3

Basement yes/no:
No

Number of heated floors:
3

Volume [m³]:
483,0

NFA calculation method:
NGF (de)

Construction type
Solid timber wall

External finish:
Exposed woodwork

Internal finish:
Wood panelling

Roof type:
Pitched roof

+ MORE - LESS
© David Schreyer
© David Schreyer
© David Schreyer
© David Schreyer
© David Schreyer
© David Schreyer
© David Schreyer
© David Schreyer
© David Schreyer
© David Schreyer
© David Schreyer
© David Schreyer
© David Schreyer
© David Schreyer
© David Schreyer
© David Schreyer
© David Schreyer, refurbished balcony
© David Schreyer, refurbished balcony
© Alexander Rieser, old wooden facade
© Alexander Rieser, old wooden facade

RENOVATION PROCESS

Architecture

BUILDING DESCRIPTION

The "Neuhäusl" in the municipality Scheffau in Tyrol was built about 300 years ago. It was farmed and inhabited as a small, enclosed farm over three centruies. In the last 20 years, the building was empty and was gradually abandoned to decay. The client has decided to extensively renovate the building and to raise it to the most modern construction standard. For building law reasons, it was necessary to obtain both the farm with a small barn with threshing floor and a housing unit for the peasant business, as well as the approved leisure residence. The external appearance of the old farmhouse has been preserved. As a result, it was forced to implement a consistent interior insulation, but this also brought the advantage of a targeted minimization of existing thermal bridges with it. Inside, the rooms have been restructured to meet the modern living standards and provide the highest comfort to new users. Due to the compactness of the existing cubature (no niches in the thermal envelope), the very low heating energy requirement and the use of modern builidng materials, the heating of the object is efficiently possible via a heat pump, a Drexel + Weiss compact unit with connected fresh water system storage.

HERITAGE SIGNIFICANCE

ELEMENTS WORTHY OF PRESERVATION
The most important character defining elements of the building worthy of preservation is connected to the exterior. The log wall construction with the sun aged wooden logs is an important character of the building. The all-round balconies and the saddle roof truss with a large canopy are typical for Tyrolean farms and, in combination with the wooden block construction, convey the typical rural building tradition.
Heritage Value Assesment
Since the farm "Neuhäusl" is not a listed building, there are no conditions of the preservation order. For this reason, no assessment of the aspects relating to the preservation of historical monuments was carried out.

State of repair

Conditions of the envelope
The building had been vacant for some time before the refurbishment. Especially the rear part of the log wall construction, in the area of the barn floor, was heavily attacked. The balconies were also in a bad condition. The log walls of the front, the former living area. were in quite good condition.

Aim of retrofit

Renovation
The main objective of the renovation was to preserve the original appearance of the farmhouse and at the same time to achieve a contemporary living standard under the aspect of energy-efficient construction.
Was there any change of use?
The former barn floor was converted into a garage with storage and technical room on the ground floor. On the first floor there is a spacious living area and the wet rooms.
Stakeholders Involvement
Architect
DI Hans Peter Gruber
Lindenstraße 2, 6020 Innsbruck
gruber@hpgruber.at
Tel.+43 512 343884
Structural Engineer
FS1 Fiedler Stöffler Ziviltechniker GmbH
Anichstraße 17, 6020 Innsbruck
office@fs1-gmbh.at
Tel.+43 512 260440
Tools used
Was the renovation process done following a specific methodology? No
Energy calculation PHPP
Hygrothermal assessment WUFI®

RETROFIT SOLUTIONS

External Walls

wooden log wall

Concrete base with internal insulation and thermal insulation system

wooden log wall

In order to maintain the external appearance of the farmhouse, it was necessary to implement a consistent internal insulation. This was achieved with a 22 cm thick cellulose insulation on the log walls. The construction corresponded to a diffusion-limiting interior insulation system. The vapour barrier was realised by a butt glued OSB board (15 mm), which also creates the airtight level. A saw-rough silver fir formwork was applied to the OSB board. The combination of capillary-active properties of cellulose and the reduction of vapour diffusion through the OSB board contribute to the functionality of this solution. Another essential aspect is the existing wood block wall. Due to the relatively high thermal resistance of the wooden wall, the temperature between the existing wall and the insulation is much higher compared to a solid stock wall. Another important factor is the air circulation through the wooden beams. The air exchange has a positive effect on the drying behavior of the construction. Despite the lack of driving rain protection on the surface of the wooden wall, a certain constructive driving rain protection is given by the surrounding balcony and a relatively high base wall, which minimizes the moisture input from outside. Due to the thick insulation it had been necessary to test this solution by means of simulations. On-site measurements had confirmed the functionality of this solution. The system has to be tested depending on the situation and climate.

U-value (pre-intervention) [W/m2K]: 0,855 W/m²K U-value (post-intervention) [W/m2K]: 0,148 W/m²K
More Details
Original wall build-up
Wood - log wall spruce:
120 mm
Retrofitted wall build-up
Wood - log wall spruce:
120mm
Other - windproof paper (Delta Vent S):
1 mm
Insulation - cellulose insulation:
220 mm
Other - OSB board (butt glued):
15 mm
Wood panelling - wooden board:
19 mm
Concrete base with internal insulation and thermal insulation system

The concrete base was necessary to eliminate the problem of rising moisture. Due to the additional distance of the wooden block wall to the adjacent terrain, the ingress of moisture through splash water is also minimized. A further positive effect is the increase of the constructive driving rain protection. In order to ensure a functioning structure in terms of building physics, the concrete base was insulated with 80 mm XPS insulation in the exterior area and later plastered. This makes it possible to create a driving rain resistant facade and to increase the temperature in the layer between the internal insulation and the reinforced concrete wall. Since reinforced concrete has a high thermal conductivity, the temperatures on the inner surface would cool down considerably without additional external insulation and lead to condensation. To play it safe, the load-bearing structure for the internal insulation in the base area was made of purenite, a moisture-resistant material based on PUR / PIR rigid foam.

U-value (post-intervention) [W/m2K]: 0,128 W/m²K
More Details
Original wall build-up
Retrofitted wall build-up
Wood - wooden board:
18mm
Wood - OSB board (butt glued):
15 mm
Insulation - cellulose insulation:
220 mm
Other - vapour barrier E ALGV 4K:
4 mm
Concrete - reinforced concrete base:
200 mm
Other - bitumen sealing E KV 5:
2 mm
Insulation - ETICS EPS / XPS:
80 mm


Windows

OPTIWIN - Lignuma

OPTIWIN - Lignuma

The old box-type windows were removed in the process of reconstruction and replaced by new windows. On the upper floor, some larger window openings were built.

It was important to the architect that the new windows should have the same appearance as the old windows. A modern passive house window made of wood was chosen where the frame is as small as possible and corresponds approximately to the appearance of the original windows. In addition, wooden crosses were inserted into the window area in accordance with the regional townscape.

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]: 5,5 New window U-value Frame [W/m2K]: 0,0
More Details
Existing window type Box-type window
Existing glazing type Single
Existing shading type NA
New window type Casement window
New glazing type Triple
New shading type NA
New window solar factor g [-] 0,53

Other interventions

ROOF

GROUND FLOOR

MEASURES TO INCREASE AIRTIGHTNESS

ROOF

The old rafters and purlins of the roof truss were checked statically, adjusted and refurbished. The wooden formwork was replaced by a new visible formwork and a classic above-rafter insulation (system Steinbacher - Steinothan) was applied.

The appearance of the roof has also changed due to the significantly higher roof construction. Nevertheless, the architect has tried to adopt the original structures. For example, the decoration of the wind chest was taken over and restored true to the original. The heart-shaped purlin plank was also reproduced and adopted.

U-value (pre-intervention) [W/m2K] - U-value (post-intervention) [W/m2K] 0,159
More Details
Original roof build-up
Tiles - clay roof tiles:
30 mm
Other - roof battens:
40 mm
Other - Rafter:
120 mm
Retrofitted roof build-up
Tiles - clay roof tiles:
30 mm
Other - roof battens:
30 mm
Other - counter battens:
60 mm
Bitumen - Sarnafil TU 222 (vapor-permeable roofing membrane):
5 mm
Other - above-rafter insulation System Steinbacher - Steinothan 120 (Steinothan 104 MV):
200 mm
Bitumen - bituminous sheeting (vapor tight) - Dörrkuplast E-3 sk:
3 mm
Other - visible wooden formwork:
20 mm
GROUND FLOOR

Since the log construction at the "Neuhäusl" farm was only supported on punctiform stone foundations and the original floor construction only consisted of an elevated wooden floor, action was necessary. The elevation prevented rising damp for the most part, but would have made renovation while retaining this structure very difficult. Another important point was the low room height in the existing building. In order to achieve a room height of 2.50 m, the entire timber construction was elevated - in a rather adventurous action - by means of wooden beams, which were attached to the block walls. To keep the block walls together, they were lashed together with tension belts. After the elevation, the entire building was undermined and a reinforced concrete foundation slab including concrete plinths was built. This measure solved the problem of rising damp and created a contemporary room height. Thanks to the massive floor construction, it was subsequently possible to apply a sealing as well as internal insulation and implement a classic floor construction.

The structure reflects the state of the art and was necessary for a damage-free refurbishment. Even in very old comparable buildings, plinths made of natural stone were often used to control the rising damp.

U-value (pre-intervention) [W/m2K] 2,0 U-value (post-intervention) [W/m2K] 0,1
More Details
Original groundfloor build-up
Floor joists - wooden beams:
100 mm
Finish - wood planks:
40 mm
Retrofitted groundfloor build-up
Concrete slab - concrete foundation + vapour barrier EALGV 4K:
260 mm
Insulation - PU-insulation (Steinothan 104 MV):
220 mm
Damp Proof Membrane - Ampatex DB 90:
0 mm
Insulation - footfall sound insulation:
50 mm
Other - PE - foil:
0 mm
Other - heated screed:
60 mm
Finish - wood parquet + glue:
15 mm
MEASURES TO INCREASE AIRTIGHTNESS

During the refurbishment, attention was paid to creating a building envelope that was as airtight as possible. This was achieved by using OSB boards for the walls. These were airtightly sealed at the joints. The windows were also integrated with appropriate care. In order to keep the sources of error as small as possible, an attempt was made to place all installations on the interior walls. Thus no additional installation level was necessary. The abut ceilings and walls were also integrated into the concept and a penetration of the airtight level was avoided. (see also the respective detailed descriptions) The rafters and purlins of the visible roof truss posed a challenge. The penetrations of the airtight level could not be avoided. For this reason, the cracks in the beams were drilled to the core with an 8 mm drill and pressed out with a permanently elastic special rubber (e.g. Dörken, Delta Than).

Airtightness (pre-intervention) [ach@50Pa] - Airtightness (post-intervention) [ach@50Pa] 0,51

HVAC

HEATING

VENTILATION

DOMESTIC HOT WATER

HEATING

Due to the extensive renovation of the building it was possible to install a completely new heating system. The heat supply for the heating and hot water is provided by a compact unit from Drexel + Weiss with a connected fresh water system tank. The heat distribution takes place classically over the heating screed. The underfloor heating is controlled by the decentralised pump system Wilo Geniax, which allows an exact dosing of the water quantity and a lower flow temperature.

The original tiled stove was no longer integrated into the renovation.

More Details
New primary heating system New secondary heating system
New system type Heat pump Stove
Fuel Electricity Biomass
Distribuition system Radiating floor stove
Nominal power 7,0 kW around 6 KW kW
VENTILATION

Due to early consideration in the planning, a very efficient duct network using flexible pipes could be implemented. The ventilation unit itself is installed in the compact unit from Drexel und Weiss. The heat recovery amounts up to 90% according to PHI. The supply air is introduced in the sleeping rooms on the respective floor and extracted via overflow openings in the bathroom and kitchen.

Because of the central situation of the distribution a suspended ceiling is only necessary in the toilet.

More Details
Original roof build-up New ventilation system
Type ventilation system Room-by-room
Type flow regime Cascade
Heat recovery Si
Humitidy recovery No
Nominal power kW
Electric power 0,33 kW
Control system
DOMESTIC HOT WATER

The hot water is provided by the compact unit of the heating system.

More Details
New DHW system
Type with heating system
Hot_water_tank Si
With heat recovery No

Energy Efficiency

Energy Performance
Energy performance certificate: EnerPHit (Passivhausinstitut)
Voluntary certificates: No
Energy Use
Heating
Primary Energy 17 (without DHW) kWh/m2.y
Consumption_estimation_After: 17 kWh/m2.y

Primary Energy
Consumption_estimation_Calculation_method: Steady state simulation (e.g. EPC, PHPP)
Consumption_estimation_Including_DHW: No
Consumption_estimation_After: 17 (without DHW) kWh/m2.y

Internal Climate

Temperature

Building owners and guests evaluate the interior temperatures as very pleasant. Due to the well-insulated walls there are no cold surfaces that cause discomfort due to a radiation difference.

Indoor Air Quality

Building owner and guests evaluate the indoor air quality as very positive.

Daylight

Due to the window openings on all sides, the rooms appear bright and attractive.

Acoustic Comfort

The acoustic comfort is described as good. The sound insulation between the floors is perceived as slightly in need of improvement.

Nel rispetto del regolamento (UE) 2016/679, ti informiamo che questo sito utilizza cookie propri tecnici e di terze parti per consentirti una migliore navigazione ed un corretto funzionamento delle pagine web. Proseguendo la navigazione del sito o cliccando su "OK" acconsenti all'uso dei cookie. Se vuoi saperne di più o negare il consenso, clicci qui.