Half-timberframed house in Alken, Belgium
Verdonck P., Beel R., Vermeiren E. & Grieten B. 2017: Energiezuinige maatregelen in monumenten met woonfunctie, Onderzoeksrapporten agentschap Onroerend Erfgoed 70/1 ISSN 1371-4678 and online available: https://oar.onroerenderfgoed.be item/450.
State of repair
Aim of retrofit
Flanders Heritage Agency
Koningin Astridlaan 50 bus 1, 3500 Hasselt
Antea Belgium nv
Roderveldlaan 1 2600 Berchem (Antwerpen)
Minderbroederstraat 52/3, 3500 Hasselt
Erfgoed & Visie
Lierselei 84 B -B 2390 Malle
Achterstraat 6b, B-9550 Herzele
Hygrothermal assessment Blowerdoor (after renovation)
Life Cycle Analysis (LCA) A life cycle analysis was not carried out but the renovation was done with respect for local grown materials.
outer wall made of wooden framework filled with loam and brickwork, rendered with loam
For energetic reasons, the loam and brickwork of the outer walls has been replaced by a combination of a framework and mineral wool insulation and wood wool fiber boards. The exterior finish of clay plaster was retained as it has heritage value. A pipe pillar was provided on the inside.
The visual perception of the wall has not altered. The modifications made to the wall (insulation on the inner side of te wall) in function of energy-efficiency were approved by the conservation authority.
The windows were in a very bad state. There were windowremains from the 17th, 19th en even 20th century. At some places the windows were absent. The remaining wooden joinery in the half-timbered house has been completely replaced by typologically appropriate - to existing model-, new joinery. The new windows have double glazing (adjustment of the profile thickness).
Substitution of all windows to existing 17th century model with insertion of double glazing (U=1,1W/m2K).
MEASURES TO INCREASE AIRTIGHTNESS
The original construction was almost completely preserved. The roof, a saddle roof with wolf end, was covered with a temporary roof construction at the time of renovation. This was placed to protect the building against further water seepage and consequential damage, awaiting the final restoration works. Because of its original character and architectural-historical value, the roofstructure preferably had to remain visible on the inside including the rafters, especially in the late 17th century core. Therefore it was preferable to insulate according to the sarking roof principle. To this end, a planking was placed on the rafters. In the 19th century section the insulation was placed between the rafters.
The visual perception of the roof has not altered. The modifications made to the roof in function of energy-efficiency were approved by the conservation authority.
Since all floors were disassembled or removed, the opportunity could be used to provide a new stable, waterproof and insulated floor structure. The floor was insulated in such a way that the current EPB requirements are met.
From the conservation point of view it was regretted that the floor tiles were not reused. They were not original and dated from 19th en even 20th century but they were typical for an earlier renovation.
New doors/ insulation inner walls and floorinsulation (first floor)
The new doors have been executed according to current standards. the visual impact on the heritage values is acceptable. The floor insulation on the first floor and the insulation of the inner walls was approved by the heritage agency
In the situation before renovation the building was leak. There were multiple openings in windows, roofs, walls.
DOMESTIC HOT WATER
Before the renovation there were only stoves for local heating. after the renovation the Ground floor is heated with underfloor heating and the First Floor is heated with radiators
There were no important interior wall elements that needed preservation. So the radiators where not a problem. But the floor tiles on the ground floor were not reused after the installation of the underfloor heating. They were replaced by a new floor.
Ventilation system D balanced ventilation with heat recovery
The installation of a ventilation system is obligatory in case of total renovation.
33.5 kW domestic hot water
Voluntary certificates: No
Consumption_estimation_Calculation_method: Steady state simulation (e.g. EPC, PHPP)
Consumption_estimation_Before: 170358 kWh/y
The building owner evaluates the temperature as comfortable.
The building owner evaluates the indoor air quality as pleasant.
The building owner evaluatde the daylight supply as sufficient, even in winter.
The building owner and guests evaluate the acoustic comfort as positive. The appartments towards the courtyard have better acoustic conditions, as they are turned away from the street