Woningtype A

Woningtype A is een rijtjeswoning met een relatief hoge noordgevel aan de straatzijde en open gevels aan de tuinzijde. De verdere constructie is zodanig, dat er veel massa aan de noordzijde van het huis zit. De straatgevel bestaat dan ook uit baksteen, terwijl de tuingevel uit lichtere materialen is opgebouwd.
Er zijn zowel in de woning als tussen de woningen verscheidene bufferzones gecreeerd diie warmteverlies, geluidshinder en brandoverdracht beperken. In de woonkamer lopen de spectraal selectief dubbelglas ruiten door tot op de grond, wat samen met de vloerverwarming zorgt voor een optimale combinatie van natuurlijke en kunstmatige verwarming.

Woningtype C

Woningtype C onderscheidt zich van type B door de toren. Door de situering vormt deze woning een stedelijk accent in de wijk Ecolonia. De extra verdieping biedt de mogelijkheid voor bijvoorbeeld een atelier.
Bij deze woning kan de hoekkamer op de beganegrond dienst doen als werkkamer. Ook de garage kan voor verschillende doeleinden worden gebruikt; atelier of winkel.

Woningtype E

Woningtype E is de andere twee-onder-een-kap woning in Ecolonia. In tegenstelling tot Type D bevindt de ingang zich aan de noordzijde.  De noordzijde bestaat uit een vrij hoge gevel die de frontwerking naar de kade op deze manier versterkt. De zuidgevel is voorzien van overstekken, veel glas en de mogelijkheid om er serres aan te bouwen.
Boven de trapkolom is een lichtkap ontworpen die op  het dak voortvloeit in een strook zonnecollectoren, die zo gevoelsmatig de woning in tweeën splitsen.

Woningtype D

Woningtype D is een van de twee twee-onder-een-kap woningen in Ecolonia. Type D heeft de entreepartij aan de zuidzijde, net zoals het woongedeelte. Utilitaire functies zoals de keuken, de badkamer en de garage, bevinden zich aan de noordzijde. De gehele begane grond is voorzien van vloerverwarming en de trapkolom wordt door daglicht van boven verlicht.

An Innocent Abroad:

                                                                                    The Netherlands Green Buildings & People PART 5

                                                                                                                    by Ian Theaker

          October 30, 1999 PART 5

          Ecolonia, Alphen aan der Rijn

          I'd heard of Ecolonia several years ago - a demonstration of green, low-rise residential development that had it all: energy
          conservation, materials selection, solar heating, water conservation and natural stormwater management, green roofs.... I was greatly
          looking forward to seeing how the buildings had weathered since their completion in 1992, and what had been learned. My hopes were
          more than fulfilled.

          Ecolonia had its beginnings with an idea floated by W/E Consultants and BEAR Architects, to create a large and very solid
          demonstration of the state-of-the-art of energy-conserving, environmentally-conscious design at the turn of this decade. The intent
          was to educate and reassure the mainstream housing sector of the practicality of novel but well-established techniques - and
          deliberately *not* to be a test-bed for experimental approaches. They managed to convince NOVEM (the agency for energy and the
          environment) to fund a feasibility study.

          With the green light from the Bouwfonds Nederlandse Gementeen (the Building Fund of Dutch Municipalities) that both the economics
          and the technical side of the project were promising, it evolved into a development of 100 single-family, terrace and semi-attached
          dwellings at a green-fields site near the small rural community of Alphen aan der Rijn. Financed jointly by NOVEM and the Bouwfonds
          Wonignbouw, the houses were intended for sale on the open market - so first costs had to be competitive, and building techniques
          suitable for widespread mass production.

          Three themes for the development echoed those of the NMP:

                    energy conservation and use of renewable energy;
                    life-cycle management, from extraction of raw resources to eventual
                    return of residual materials; and
                    quality and durability improvement.

          These themes were further elaborated into nine areas of concern for the houses' architectural programs:

                    Energy Conservation:

                              reduced heat loss (BBHD - Bakker Boots Van Haaren Van der
                              Donk)
                              solar energy (J.P Moehrlein)
                              energy conservation during construction (Architektenburo
                              Hopman)

                    Life-cycle Management:

                              water consumption and reuse of building materials (BEAR Architekten, Gouda)
                              extended lifespan & minimal maintenance (Architektenbureau Alberts & Van Huut)
                              construction for flexibility in use (Lindeman cs Architekten & ingenieurs)

                    Quality Improvement:

                              acoustic insulation (Workgroep Woningbouw en Energiebesparing)
                              health and safety (Peter Van Gerwen)
                              "bio-ecological" building (Architekten ArchiService)

          A different architectural team was selected to focus on each of these themes, rather than get a cookie-cutter community from a single
          design team. (Their names follow their focus, in brackets - I believe in credit where credit is due!) Overall planning of the community was
          done by the renowned Belgian planner, Lucien Knoll.

          At each intersection and at the ends of housing terraces, an extra storey on the buildings emphasizes the streetscape, and creates a
          sense of entry and urbanity. The nine designs are mingled, to avoid uniformity, and located to create "squares" and social spaces, with
          no setback from the streets. Streets, paths and squares are lit with high-efficacy lamps.

          All of the buildings had the same general requirements:

                    environmentally-aware materials selections
                    crushed and recycled concrete aggregates
                    anhydrite cast floors
                    household waste separation and recycling facilities
                    solar water heaters
                    fossil-fuel space heating equipment to have high-efficiency, low-NOX burners
                    no use of tropical hardwoods
                    no use of bituminous products
                    no radon penetration to interiors
                    no use of CFCs in equipment and materials

          Two energy targets were set for space and water heating and cooking; <300MJ/cu.m and <220 MJ/cu.m; the tighter standard was
          required of the "Energy Conservation" theme buildings.

          The rural site, midway (about 30 kilometers) between Amsterdam, den Hague and Utrecht, had previously been designated for
          increased growth. Like all of the Netherlands, the site is flat; an existing natural waterway bounds the south side. The Ecolonia houses
          are only a part of a larger development, which totals some 300 dwellings in a variety of densities and forms. Knoll's plan created small
          central lake to provide a focus for Ecolonia, to treat storm runoff and allow it to infiltrate into the ground; the little overflow from the
          pond runs to the natural waterway via a small surface channel planted with rushes and cattails. Extensive native planting and gardens
          are used to separate the buildings, with many deciduous trees for shade in summer, and allow solar exposure in winter.

          Ecolonia was consciously designed with the pedestrian having priority. Streets have a variety of widths, but have narrow and winding
          sections, and are mostly cobbled. There is no differentiation of car, pedestrian or bicycle paths, nor is there a through-route for cars.
          Knoll used a mix of east-west and north-south blocks to create variety, deliberately sacrificing optimal solar exposure of the housing.
          Even so, almost all of Ecolonia's houses have a significant passive solar contribution, and active solar collectors.

          There were several building design responses especially worthy of note. Moerhlein and BEAR selected wood-frame construction - as
          yet unusual in the Netherlands - largely on the basis of lower environmental impact over the life-cycle than the more common brick,
          concrete or lime-sandstone block.

          Several houses used recycled wall and roof cellulose insulation - with detailing that reflects the warning by building scientists from the
          Netherlands Organization for Applied Scientific Research (TNO)to ensure that avoiding damp is imperative. One designer proposed
          compressed cellulose insulation below the floor slab - which was rejected due to this concern.

          All the houses underwent airtightness testing during construction, to standards considerably higher than those required by code.

          Water-conserving fixtures were universal; composting toilets were avoided due to concerns with proper operation and maintenance by
          the owners. BEAR collected rainwater for toilet flushing and clotheswashing, and recovered heat from wastewater.

          Moehrlein incorporated solar conservatories in their buildings, but they were found to overheat in the summer due to the lack of
          shading (and - my surmise - insufficient thermal mass).

          Several designs (BBDH, Moerlein, Lindeman and Van Gerwen) had balanced ventilation via heat-recovery ventilators; the others used
          switched or continuous exhaust fans with window-frame inlets; and one used exclusively natural ventilation through carefully-placed
          window-frame inlet and outlet vents.

          Most buildings followed the Dutch standard practice of hydronic heating, but with radiators oversized according to practice at the time
          to reduce temperature differentials and pumping energy. In most cases, the high-efficiency boilers supplement the solar domestic
          water heaters as required; Hopman also had solar collectors for space heating. Two designs had hot air/furnace heating systems -
          uncommon in Holland.

          ArchiService's design was unique in several respects. These were the only homes that had vegetated roofs. Rafters were covered with
          20mm cork and a 1.3mm EPDM membrane; sloping roofs were further insulated with 50mm of mineral wool, and flat roofs with expanded
          clay granules. These were then covered with 150mm of peat substrate and grass turfs. As well, in these buildings, particular attention
          was paid to avoiding electromagnetic fields, and global and cosmic radiation. Most interesting to me was the design of hydronic radiant
          "heat walls", developed in conjunction with suppliers. These consist of plaster applied over cast lime-sandstone blocks that have
          channels for hot water tubing. Insulation is placed outboard of the blocks, and the exterior finish is brick.

                    Lessons Learned

                    In subsequent monitoring, seven of the nine Ecolonia designs met their heating energy targets of a 25% reduction from
                    current standard practice in 1991; their annual primary energy consumption varied from 181 GJ/cu.m (Archiservice's
                    "bio-ecological" design) to 288 GJ/cu.m (226 to 916 cu.m of natural gas for space heating; numbers are normalized for a
                    standard 300 cu.m volume). The other two projects exceeded their targets only slightly.

                    Solar energy - even with the Netherlands' cloudy, rainy winters, and with sub-optimal building orientation - contributed to
                    this performance, especially in the shoulder seasons. (Take note, Vancouver designers!) However, many collectors required
                    fine-tuning and commissioning the first year.

                    Annual electrical energy varied from 2765 to 4374 kWh/household, comparable to 1991 average consumption of 3079 kWh.
                    (Compact fluorescent use was already standard practice.) PV arrays were not used due to high initial cost, except for small
                    ones in the BBHD designs, for pumping through the solar water heaters.

                    Five of the nine designs failed to meet the high air-tightness standard, indicating that more detailing and on-site supervision
                    would be beneficial.

                    As mentioned before, solar conservatories and rooms with large south-facing glazing for passive solar heating, require
                    shading (and probably thermal mass) to prevent summer overheating.

                    Heat recovery ventilators were found to be significant electricity consumers, and did not make large contributions to
                    heating energy savings in the Dutch climate. Further, they were the least satisfactory to the occupants, due to their
                    continuous noise. It was recommended that warm ventilation air should in future be supplied to the living rooms, rather than
                    the bedrooms - a contradiction to Canada's National Building Code.

                    Building material selections for lower environmental impact was a positive experience for the designers and builders.
                    Crushed concrete aggregate use was straightforward; alternatives to PVC plastics were easily found, with no compromise in
                    quality or service; anhydrite concrete floors were healthier for the workers, improved airtightness and provided smoother
                    surfaces. Wood-framing reduced life-cycle environmental impact compared to constructions more common in the
                    Netherlands, but required additional care in construction, and in maintenance (no surprise to Vancouver's Barrette
                    Commission...) Laminate use was successfully limited; but too few interior finish options offered to the buyers resulted in
                    later modifications - and materials waste.

                    Airtight floors barring radon penetration, and selection of finishes with low emissions, improved occupants' perception of air
                    quality inside the homes.

                    Residents were most satisfied with the hydraulic heating systems - particularly the radiant floors and walls. They were less
                    satisfied with the hot-air systems, especially with their lack of individual control of temperature in each room, dry and dusty
                    air, noise, and distribution of cooking odorous. These last two complaints were also leveled at the heat-recovery ventilation
                    systems. The wholly natural ventilation system gave the most satisfaction; and then the exhaust-only systems.

                    Construction costs were kept competitive - but only after the original designs were re-examined for savings. Prices ranged
                    from 191,000 to 298,400 NLG in June 1992, comparable to market prices for the average homebuyer.

          I spent a fine afternoon wandering the site, looking and photographing the buildings, streets and squares. The houses are all in fine
          shape; and ArchiService's grass roofs, and the vine-covered trellises at the corners of the BEAR designs are especially beautiful. The
          pond creates a very healthy, tranquil - and desirable - focus to the community; it is largely surrounded by reeds, with a resident family
          of ducks, which delighted the small kids I saw playing as I sat on it's shore. The kids had no fear playing in the streets, and the design
          was such that a parent could easily keep an eye on them from their homes. Anton Alberts' brick houses struck an odd note, with their
          tilting rooflines and window frames - but fit superbly with their gorgeous gardens (one of the ducks was peacefully asleep on the patio
          between the house and the reeded overflow channel). Obviously, their residents take a great deal of pride in their homes, and for
          good reason.

          I also had a chance to speak with Martin Regenboug, one of Ecolonia's first residents, and steward of the Informatiecentrum Ecolonia.
          He is the very satisfied owner of one of ArchiService's "bio-ecological" row homes.

          He obviously loves his terrace house, and the community - he was most generous with his time, information and hospitality. Martin found
          me sitting in the small grassed space behind his home, where I was watching (several!) flocks of birds feed and chatter in the
          vegetation that covered his roof. We had tea in his back yard, at a beautiful handcrafted birch table that once formed the base of a
          model of Ecolonia, for the benefit of tourists like me. He was especially happy with the wall heating system - silent, comfortable, and
          economical. He could not recall *any* problems with any of the homes - and he's been keeping track since the beginning.

          Apparently, general interest in Ecolonia has died down in the past few years; I was the first visitor he'd had in months. It seems that its
          lessons have already been internalized by the Dutch mainstream - either that, or the novelty value has disappeared. He was
          disappointed, however, in the lack of environmental fervour exhibited by his neighbours, whom he felt took the community, and what it
          represented, for granted. He told me that the market value of Ecolonia homes is significantly higher than the other homes in the larger
          surrounding development, for several reasons. The proximity to the pond, the lower operating costs, and the healthy construction are
          all selling features that command a premium - much the same experience in Village Homes in Davis, California. Are any mainstream
          Canadian developers in the crowd?