**Document:** Grenaby House Supporting Statement **Application:** 13/91513/A — Approval in principle for erection of a two storey contemporary extension to rear of dwelling **Decision:** Application Withdrawn **Decision Date:** 2014-01-28 **Parish:** Malew **Document Type:** report / planning_statement **Source:** https://planningportal.im/a/42649-malew-grenaby-house-extension-dwelling/documents/1363919 --- # Grenaby House Supporting Statement ## Grenaby House – Additional Supporting Information ### Mission RECEIVED ON 20 DEC 2013 GRENABY HOUSE Grenaby House, within its setting, is unique... it was unique when it was first built and it is still unique today. The mission for this development is the preservation and restoration of the core essence and beauty of Grenaby House; to maintain the property's relationship with its adjacent neighbours and surrounding environment; to return this beautiful building back to a once landmark building through the renovation of its existing structure and future proofing the building with a exciting new architectural addition. The challenge of the new extension is to make it exciting, sustainable, eco-friendly, technologically advanced and yet at the same time for it to subtly disappear in its own environment and not to lose the integrity of the original building. Through thoughtful design and a high attention to detail, the intention is to build a unique structure that compliments the original house and gives it longevity. Grenaby House has always been an outstanding property, and this scheme provides an exciting opportunity to enhance the original merits of its architecture by producing a piece of unique design to make Grenaby House once more lead the way with a contemporary vision while at the same time being sympathetic to its surroundings. ### History Grenaby House is a landmark building, in an unrivalled setting, alongside a picturesque river and beautiful stone bridge. It is nestled in a wooded site with a blend of mature and developing woodland. It is one of two almost identical houses in the area, it's 'sister' house being half way along the Ballamaddrell to Grenaby Road. Of the two properties, Grenaby House has much larger windows. At the time it was built it took its style from a grand Georgian country house and would have been very impressive when first viewed. It is with this in mind that it is very important that the integrity of the original building is retained. A former dwelling sat on the site between the old barn and the current house's location. When this fell into disrepair the owner approached a local builder who was in the process of building the 'sister' house, and so the foundations of the current Grenaby House were laid. ## Grenaby House Due to its classical proportions the initial impression is that this is a good sized house but in reality the rooms are very small, compared to modern standards of living. The original accommodation consisted of living and kitchen areas at ground floor, with three small bedrooms and a bathroom on the first floor. The main staircase continues to a second floor where, although there is restricted headroom at the eaves, there were additional rooms with small windows. Over the three floors the total floor area, as measured to the outside of the walls, is 212m². However the useable floor area is greatly reduced due to the thickness of the stone walls. The property was purchased by the current owner in 2006 at a public auction. The auction documentation promoted the house as having tremendous development potential subject to planning permission. There was no indication at that time that the property was being considered for protection as a registered building and that major planning restrictions might be placed on the redevelopment of the property. The existing house was already in a very poor state of repair when purchased. The interior fittings and woodwork were riddled with rot and infestations and deemed unsafe and accordingly removed. The exterior walls appear structurally sound but require repointing with lime mortar, and the roof structure and sash windows need to be completely replaced. Renovation work to the house will require internal dry lining and insulation of the internal walls to bring the building up to modern standards which will further reduce the useable internal floor area. The costs for this renovation work are comparatively high and the accommodation provided by the original footprint, without any kind of extension, do not justify the work. In discussions with the conservation and planning officers, it was agreed that the character of Grenaby House from the roadside should be protected. Extensions to the side of the property were not deemed appropriate and the front elevation should remain untouched. However, it was clear that as the building was in such a poor state of repair, and with limited internal space, that some form of extension was required to bring this property back into use and justify the investment needed to restore it. Initially, having reviewed the options and the financial implications of the project, the building was reluctantly offered for resale. The house has been on the market for several years. Recently the owner has reviewed the project and researched the local housing market. He has taken further advice as how it might be possible to progress the scheme, renovate this building, and provide a suitable level of accommodation. ## The Site Grenaby House is set on the north edge of a 1 acre plot with half of it on the road side and the other half bounded by a river. Although there is an adjacent road and a public footpath, the site is in a relatively remote location and in a gentle dip in the landscape so that it is generally screened from the surrounding countryside. The house is set proudly amongst its own grounds and has a 'wooded glen' feel to it. With this in mind it was felt that landscaping and the setting should be an integral part of any new proposals for the building. A copy of the Land Registry plan from 1869 shows that originally there had been several buildings on the site. These include Grenaby House, two outbuildings, a stone barn and an ancillary building which is on the site of the proposed extension. The site was very overgrown when bought at auction, and many trees had fallen or been damaged during a recent storm. Originally clearing the site opened up and exposed it from the road; however the boundary planting is starting to re-establish itself and once again screen the site and house from public view. The site is of a good size and is suitable to accommodate a substantial extension without affecting the neighbours or dominating the landscape. The proposed siting of the new extension draws on its surroundings whilst minimising its impact on the environment and neighbours, blending in with and enjoying its stunning position. It is key that the new development embraces a sense of seclusion within the boundaries of the site, and that the positioning and orientation is carefully considered so that it forges a sense of connection with this breathtaking location. ## Landscaping The orientation of the property and the typography of the site lend itself to developing the rear of the dwelling which will have less impact on the main front façade. There are limited views of the site from the road and by retaining mature trees and enhancing the landscaping along the boundary, the new extension will be concealed to retain the integrity of the original house. Areas of fallen trees have previously been cleared. These have been documented and advice taken from the Forestry Department. The area proposed for the extension is clear of trees and no felling or lopping of the remaining trees is required. At the suggestion of the Forestry Division a tree management scheme should be prepared to outline the proposals for the care and protection of the existing trees especially those along the boundary. They will provide further assistance in this matter when planning approval has been obtained. It is proposed that native species of hawthorn, beech, mountain ash, will be planted to supplement the existing trees. These will be planted in such a way as to provide privacy for the main house and extension from the road and public footpath. On the boundaries with the road, areas of the site will be planted and contoured to enhance the screening and minimise the visual impact of the property so that it is concealed by its natural setting. ### Design concept The original design of Grenaby House and its setting should form the primary influence on the design of any extension. It should not dominate or detract from the original building or the character of the area but instead play a supporting role that respects Grenaby House. It was suggested by the planning officer and conservation officer that a modern design, using contemporary and sustainable materials would meet this criteria. The proposed design draws not only on architectural aesthetics but on technology, sustainability and energy efficiency that was not available when Grenaby House was originally built. The new development gives an opportunity for modern living that the original house alone, in its original form and size, can not achieve. It is important that any proposal should ‘disappear’ into the surrounding environment through the use of sympathetic and carefully selected materials. With this in mind, the majority of the extension will be made of glass, visually transparent, reflecting and mirroring its environment, and so at first glance it subtly disappears. A glass pavilion in a woodland setting. For a house of this period, the windows to the front elevation of Grenaby House are of a very generous size and the quality of natural light would have been a great feature. It is appropriate that glazing and the quality of natural light is also a feature of the new extension. Original proposals for the extension roof were for a copper finish which over time would turn green through verdi gris. However the design has evolved and the current preference is for a living sedum ‘green’ roof that would have a much more immediate effect, helping the building merge into its natural surroundings. Between the original house and new extension will be a glass linking structure to define the new and compliment the old. This will form a clear definition between the two and once again maintain the integrity of the original house. ## The Pavilion The principle of the lightweight 'pavilion' structure on this wooded plot, takes advantage of the woodland and riverside views. Throughout the design the intension was to retain Grenaby House's architectural integrity and yet at the same time, through the use of modern materials, a visual rhythm and the almost invisible simplicity of the new extension, produce a scheme that builds on and adds to the architectural merit of the dwelling. The orientation and location means that the extension is mainly screened off from view from the front elevation of Grenaby House. The pavilion is then broken up into a series of elements to minimise the visual mass of the building. The proposed extension is set at an angle to the main house so that the main aspects maximizes natural daylight and faces towards points of interest e.g. the bridge and river. This less formal layout contrasts with the formal siting and proportions of the existing house. The overall impression of the pavilion is of a lightweight floating structure with large areas of glazing. The glass provides high levels of natural light into the building with panoramic views out so that the occupants feel part of the landscaped woodland. The glazing will also reflect the surrounding so that the trees and their reflections merge and blur the boundaries of the building. There will be panels of horizontal cedar boarding interspersed with the glazing to provide a degree of privacy to bedrooms etc. The cladding will be left with a natural finish and will quickly mellow and soften so that, although obviously a modern building, the palette of materials, textures and colours will sit comfortably on this wooded plot. The main roof over the living accommodation will be a lightweight canopy structure, that overhangs the glazed walls to provide a degree of solar shading, and is supported by delicate steel columns taking their influence from the surrounding trees and leaf canopy. The pavilion is designed to the same high standard on all elevations so that it is not compromised in quality when viewed by the public from either the roadside or riverside path. Overall the orientation and elevational treatment of the pavilion means that Grenaby House remains the dominant element and although of differing architectural styles the two parts of the building complement each other and the landscape. The proposed renovation of Grenaby House and the concept of the 'pavilion' extension has been well received by the conservation and planning officers. However this is a high cost solution and needs to take into consideration financial return to make the project viable. The applicant has taken advice from a leading island estate agent. They have suggested that from their experience there is a shortage of suitable, high quality 4-5 bedroom properties and that to be economically viable the floor area of the property should be no less than 5,000ft² (approx. 465m²). Many new residential properties of this size and price range tend to be of a predictable 'executive estate' style of design. A modern contemporary house such as proposed for Grenaby House would be an asset to the Isle of Man and appeal to high net worth clients interested in investing in the island. Based on preliminary sketches, the new pavilion extension provides approximately 310m² of living accommodation with an additional 40m² glazed link. This equates to an extension of approximately 165% of the area of the original house. While the size of the extension is greater than the 50% stated in Housing Policy 15, an extension of this size is required to achieve the intended levels of living accommodation and sustainability to ensure that the original property can be saved from ongoing deterioration. In addition, to be able to draw on and maximise the benefits of many of today's environmental technologies, for example ground source heating (as discussed in more detail in the 'Sustainability' section below) the scale of the building needs to be of a sufficient size to warrant their usage. The proposed scheme will safe guard Grenaby House well into the future. It should be noted that Housing Policy 15 does allow for extensions greater than 50% and not of a traditional nature in certain exceptional circumstances. The style and setting of Grenaby House and the contemporary design solution does make this an exceptional case that will still sit well within this quiet, out of the way, countryside location. ### Sustainability One of the greatest and most exciting opportunities for Grenaby House is to improve the energy efficiency by incorporating sustainable technologies into its design and making it eco-friendly. It is hoped that concentrating on the latest energy efficiency technologies will lead the way and encourage other projects, resulting in a significant reduction in energy use on the Isle of Man. The scheme will address environmental sustainability by incorporating the highest levels of insulation to the floors, walls and the roof together with triple glazed windows and advanced heating and lighting systems. Heating and energy consumption will be supplemented by investigating ground and air source heat pumps, solar panels and solar tubes (a common method of introducing greater sustainability benefits to a property) - each complimenting the efficiency of the others. A heat recovery system will be used internally where extracted air is used to warm incoming fresh air. Rainwater harvesting systems will be incorporated through the roof and guttering as a method of water conservation. The water can be used for washing machines, toilets, garden irrigation etc Such systems and investment in the building benefit from an economy of scale and the proposed size of the extension make this viable. 6 | Page Installing a high efficiency condensing boiler which can be backed up by a ground source heating system, and the installation of low or zero carbon technologies such as solar thermal panels or photovoltaic tiles on the roof to help heat the water, could all contribute to these efficiencies. To compliment the efficiency of the heating systems a 360° wood burner will be provided in the centre of the living area. This investment through sustainable efficiency, technology and lighting will extenuate this existing property whilst making it very economically and environmentally friendly. This project provides an opportunity to make a difference - to achieve sustainability. ### Vision This is a bold and exciting project that relies on the confidence of producing a solution of exceptionally high design to modern requirements and standards. A scheme that aims to provide something that in itself is unique, but also compliments the uniqueness of Grenaby House The merits of the design can, in part, be explained by the material choices and sympathetic landscaping that blend in with the site and its locality. The new structure draws on inspiration from its position and the natural beauty around it and by reflecting it, quite literally, in its exterior facade. The vision for Grenaby House is a discrete, secluded oasis embracing the latest advances in sustainable living and demonstrating how old and new can successfully fuse together. The revitalised Grenaby House will be an exemplar of how a 21st century house can be incorporated into the countryside, and historic conservation areas, as part of the continuing evolution of domestic architecture and it will showcase the forward thinking of the Isle of Man. --- *Data sourced from the Isle of Man public planning register under the [Isle of Man Open Government Licence](https://www.gov.im/about-this-site/open-government-licence/).* *Canonical page: https://planningportal.im/a/42649-malew-grenaby-house-extension-dwelling/documents/1363919*