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We have a Code 6 house on the architect’s “drawing board” at the moment, (Code 6 is the highest band in the “Code for Sustainable Homes” and amongst other things it means that the house will be carbon neutral). The trouble is, this house is supposed to look like a nineteenth century barn conversion. The site is within a courtyard group of recently converted barns in residential use. The other barns have slate roofs and are a mixture of local stone and black stained horizontal weatherboarding. So… typical agricultural buildings then! There is a tiny bit of salvaged brick and stone on the site which will do for a modest plinth near ground level, but no slate. Extracting more walling stone and roofing slate from the ground is out of the question. Where do we go from here? Timber is becoming widely respected for building purpose due to the fact that, as they grow, trees trap CO2 and are therefore considered carbon neutral and a fully renewable material. We had adopted a timber frame for the structure early on but had the idea of using Western Red Cedar for all of the external cladding – walls of feather-edge boarding and shingles for the roof. We checked into the attributes of this timber and were thoroughly impressed with it’s C.V and it’s capabilities.
Western Red Cedar: The Data 1. Sustainability The first point to make is that a sustainable producer needs to be identified, but helpfully the WRECA (Western Red Cedar Export Association) provide product certification and chain of custody tracking to ensure excellent forest management and environmental protection. 2. Appearance When it comes out of the sawmill, cedar has a rich amber/ sienna brown colour with a satin sheen. (By the way it also smells terrific – great for lining saunas) This colour can be retained with a lot of effort and the application of various chemical concoctions to keep the impact of ultra violet light under control. However, left untreated it will turn grey – this gives an appearance not dis-similar from weathered Welsh slate. Also, grey timber cladding is actually more historically authentic than black boarding. For thousands of years people all over the world built with wood and left it exposed to the elements – it just went grey. Stain is a relatively new invention and quickly took the place of tar-based products. Some naturally occurring tar or pitch might have been used where available, but it wasn’t until coal tar began to be produced – as a by-product of turning coal into coke or gas – that economical quantities of tar came into circulation. So the “black barn” is a modern phenomenon, relatively speaking. 3. Intrinsic qualities Western red cedar (Thuja Plicata) fits the bill in many ways, including:- a. Low density – The cellular structure is very open making it less dense than most other softwoods, so the roof dead load is less and rafters can be smaller. b. Better insulation – As a function of the low density, the entrapped air insulates, keeping internal heat in, in winter and reducing solar gain in summer. c. Low shrinkabilty – The cell structure also creates an extremely stable material, twice as stable as other soft woods used in construction. It remains flat and straight after cutting and holds nails securely. d. Resin-free – Unlike other softwoods, there is virtually no pitch or resin in cedar. This means the unsightly bleeding of resin from knots is avoided. e. Self-preserving – The heartwood contains high levels of “Thujaplicins”, which are natural wood preservatives that protect against moisture, decay and insect attack. In fact these preservatives are toxic to fungi. f. Good workability – These trees produce an exceptionally consistent timber, close and uniform grain with few knots. It is less likely to split and warp as it is being worked compared to other soft woods. g. Resistance to fire – It has a higher resistance to the spread of flame than other soft woods and also a better rating for retarded smoke generation. h. Durability – The service life of cedar cladding is 40-60 years compared to 20-30 years for generic European Redwoods.
So Western Red Cedar wraps it up really – we couldn’t go wrong and look forward to putting it together on site. P.S It is also very useful for making all sorts of other things such as beehives, canoes, boat frames and guitars. Good luck.
Acting on behalf of a well-established domiciliary care and support provider in the North West, the specialist healthcare team at CADS was set the challenge of designing a new dual-purpose head office and day care facility; enabling the business to continue to grow effectively over the coming years. Our client had already identified a potential new base in the form of a derelict coach house on the outskirts of a new-build commercial estate and in order to raise the necessary funding for the project, our client required a detailed space investigation to consider the potential clerical capacity and care facilities that could be incorporated in the building.
The existing derelict coach house From the outset we knew that a detailed site visit was essential in order to gain a clear understanding of the location and potential of the space on offer. During this time the team collected a range of survey data and the building was extensively photographed to establish a base set of existing plans, forming the basis for our initial block planning and feasibility study. Using a cross section of experience, government guidelines and practical thinking the team quickly established that the best way forward was to allocate the first floor to clerical space and the ground floor to care, separating the two functions and allowing each to operate as effectively as possible. After a number of iterations and in close liaison with the client, the ground floor was developed into a highly flexible space for day care that not only offered attendees the opportunity to relax in a range of safe environments, but it also offered the opportunity to small businesses to rent space for hairdressing, chiropody and other treatments; further supplementing income for our client and adding extra value for visitors.
Additionally, the team at CADS designed a secure courtyard garden that would further engage visitors by employing the latest research and guidelines for elderly care. This included creating seasonal interest with trees, shrubs and plants to offer a changing vista throughout the year and the use of aromatic plants that are close to path and seating areas to provide sensory stimulation for the visually impaired.
The clerical space on the first floor was accessed from the reception via a dramatic staircase to an open gallery; this really reinforces the professional nature of the business and offers a clear distinction between the different functions. Some of the key spatial requirements included the provision of a dedicated Director’s office with breakout space, an open plan administration office with room to grow into, a records office to comply with data regulations and a purpose built training room.
This particular project was rapidly turned around by the team, with a varied range of deliverables to support our client’s internal debate and stakeholders presentations. Our core document pack included loaded plans, elevations, individual equipment C-Sheets for each of the main rooms alongside a detailed proposal for the courtyard. If you have a similar project in mind for a care home, day centre or any other health related space then please get in touch. Our skilled and professional team are on hand to answer your queries and help you to make the most of any building, establish potential costs and review the overall capacity and functionality of the space.
Proposed front elevation
Our team over at 3d Architects were involved in a local development this year, during which they were faced with various interesting challenges relating to the architecture. Ken Wallace, Associate Director at 3d Architects, discusses these challenges and his approach to them below. We hope the case study might help you in the future when faced with any similar architecture, planning, or site development challenges. To start, this project required extensive negotiations with various departments of the local authorities – the issues faced included the following:
First of all, here’s a little background on the project: Pottergate is a medieval street in within the Norwich city walls to the north-west of the market and lies within the central conservation area. There had previously been planning permissions on the site, but this had expired and a new policy relating to the use of renewable energy prevented a simple extension of the old consent. Planning Permissions – the challenges The new owners of the site and the local authority officers were keen to improve on the previous planning permissions for the site, and instructed 3d Architects to take this forward. However we were immediately presented with constraints by the Conservation Officer, the County Archaeologist, the Highways Engineer and the Planning Officer! The planners were quite clear that due to the tight urban grain, the only acceptable site layout would be a pair of parallel blocks, one fronting the street and the other set back behind an internal courtyard.
The Conservation Issue The site context includes many Georgian and Victorian buildings, set on the back of the pavement and generally three storeys high. There are also listed buildings on both sides and opposite.
This archive photograph from around 100 years ago shows the site frontage behind the two nearest carriages. The old dwellings were destroyed during the Second World War and the site was not re-developed until the 1960’s when a printing works was built. An alley way through the frontage gave access to a Baptist chapel; this had an associated Sunday school building but also a cemetery. Our Architectural Proposal Our task was to generate a frontage compatible with the rhythm and strata of the adjoining buildings but not one that is a straight copy of the old townhouses. Working very closely with the local authorities the final solution saw the front block set on the back of the pavement, and conceived as a pair of townhouses with an adjoining building that incorporates a modest arched entrance to the courtyard. The whole block is three storeys high with the principal rooms arranged at the front. There is a strong vertical emphasis to the proportions, with a repeating pattern of windows and doors that echoes the rhythm of the Nineteenth Century neighbours. The materials for the walls and roof are sympathetic to the historic nature of the area, primarily red stock brick and clay pantiles.
Introducing the arched entrance allowed an increase in usable floor area whilst improving the continuity of the street frontage (which historically had only narrow breaks in it). The scale of the site access point in the previous approval was felt to be out of character with the old street. The rear block is of a different design but related through the language of the materials. The ground slopes away to the north so the rear building is set about 1.0m lower and is designed as two and a half storeys high thus lowering the eaves. The roof is also largely hipped to reduce the extent of over-shadowing on the neighbouring properties.
The scheme includes a range of sizes of apartments from 41 to 86 sq metres gross internal floor area. Some of the units also have the facility for “Working at Home”. The Archaeology Issue As a result of its location within the old city there is the possibility of various layers of archaeological material on the site. However, previous excavations had indicated that the construction of cellars in Victorian times had removed quite a lot of the earlier deposits. There is still a significant issue over the human remains in the old cemetery, compounded by the presence of a crypt, below the floor slab in the location of the former chapel, containing further burials. Dealing with a potentially archaeological site – our response We negotiated with the Ministry Of Justice to get clearance for the proposed foundations and arranged the site layout (e.g. the location of the courtyard garden and the parking spaces), to minimise the disturbance to the ground in the sensitive areas. We are co-ordinating further archaeological excavation work with the County Archaeologist so that all historic material uncovered during construction can be recorded for the local archive. We worked with a structural engineer to devise a piling scheme that had the minimum of impact on the ground, (bearing in mind that the ground conditions are not particularly favourable – a chalk layer is relatively near the surface).
The Highways Issue The city council would have preferred this to be a car-free development, however as a city-centre development, cars were recognised to be a necessary inclusion. The Highways Issue – A Compromise We ended up with eight parking spaces for the full development. Each flat has been given a cycle shed. There are also cycle bays for visitors. This is considered a highly sustainable location so the occupiers will benefit from easy access to all the facilities of the city centre. The re-design of the car parking area allowed for a larger communal garden and a reduced area of roadway, whilst still increasing the number of car spaces on the site. The client was keen to install a gate at the entrance to prevent un-authorised use of the car park; we were able to secure the planners and highways agreement to this. Dealing with refuse on site is an important issue and we were able to provide a solution that discretely accommodates the shared bins in accessible locations and allows for the current and future range of separation for re-cycling different materials. Ensuring the Conservation of Natural Resources The current planning policy on energy requires that at least 10% of the energy consumed by the development has to be provided on-site. Our starting point was to design buildings with very low levels of consumption of natural resources. They are highly insulated and placing the main rooms on the sunny front side makes the most of Solar Gain. Heat recovery ventilation systems are included. The front, southern roofs slopes are ideal for positioning photo-voltaic panels to recover energy from the sun that is converted to electricity. The calculations demonstrate that this comfortably exceeds the 10% threshold. This arrangement also takes advantage of the Feed-In Tariff scheme, selling surplus electricity back to the National Grid. Other renewable technologies were explored but found to be unsuitable for this urban location; wind turbines were ineffective in this city location, air-source heat pumps were too noisy, ground source heat pumps would disturb too much archaeology and deliveries and storage of fuel for biomass boilers was prohibitive. Solar thermal heating would have been viable but was likely to generate surplus energy that could not be harnessed. The development also incorporates low-energy lighting and domestic appliances as well as utilising the latest in low water-consumption bathroom and shower fittings. Other issues The site was previously fully occupied by the factory and its car park, but will now have a shared garden in the centre of the scheme, together with some small areas of private garden for some of the ground floor flats. The boundary brick walls will be repaired and strengthened. The soils on the site contain further risks which are also being addressed. There is Japanese Knotweed present so a considerable quantity of soil will be removed and replaced. There is also the potential for contamination of the ground related to the former printing works so a further investigation is being carried out before work starts on site. A Summary Pottergate is a pleasant street close to the heart of Norwich in an area that is currently benefitting from a period of regeneration. This scheme will provide a sympathetic reinstatement of the street scene, respecting the older buildings nearby. It sensitively handles the constraints that arise from being in a historically significant location, enhancing the location from a variety of viewpoints and gives a new lease of life to a site that has been overlooked for some time. If you’re faced with a similar architectural challenge, share your story with us in the comments section below. 3d Architects are also happy to offer advice and services to help you in negotiations with land owners, local authorities etc. You can find more information on their website: www.3darchitects.co.uk.
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