Building Regulations Application submitted for a new residential extension in Copthorne, Shrewsbury.

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Following planning approval for a single-storey rear extension at the property in Hafren Road, Copthorne, Shrewsbury the client the appointed En-Plan: Planing & Architecture to prepare and submit a building regulations full plans application to Approved Inspectors in Shrewsbury that covered the technical detail required for the build. The  application is progressed rapidly  and we received approval for the scheme in August 2020.  As part of the application we were able to provide a thermal efficiency calculation to offset the large amount of glass used, and structural element specification in the form of a Catnic Lintel to allow for the extension to be opened to the main unit and allow light and space to flow.

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What are the benefits of using a Catnic Lintel?

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Catnic lintels are a popular choice in construction for several reasons.The first is that Catnic lintels provide strong structural support to openings such as doors, windows, or other wall openings. They are designed to bear the load above the opening, ensuring the stability and integrity of the building structure. Catnic lintels are designed for ease of installation. They come in various sizes and configurations to suit different opening requirements, making them versatile and adaptable for different construction projects. Their installation typically involves placing them across the opening and securing them to the surrounding masonry or concrete. Catnic lintels are engineered to meet relevant building regulations and industry standards, ensuring compliance with structural and safety requirements.

 

We can liaise directl;y with building control to ensure the lintels specified will mee their high standrds as part of a technical build detail project.

 

When is a thermal efficiency calculation required?

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In England, thermal efficiency calculations are typically required for extensions as part of the building regulations. The specific requirements may vary depending on the circumstances of the extension. If you are constructing a completely new extension, it is likely that a thermal efficiency calculation will be required. This is to ensure that the new extension meets the minimum energy efficiency standards set by the building regulations. The calculation will assess factors such as U-values, insulation, and heat loss to demonstrate compliance. If the extension involves significant alterations to the existing building, such as changing the external walls, roof, or windows, a thermal efficiency calculation may be necessary. This is to assess the overall energy performance of the extension and ensure that the alterations meet the required standards. The requirement for a thermal efficiency calculation may also depend on the size and function of the extension. Larger extensions or those intended for specific uses, such as habitable spaces or rooms with high energy demands (e.g., kitchens), may require a more detailed assessment of thermal efficiency. t's important to note that the specific details and requirements for thermal efficiency calculations may be subject to updates and changes in building regulations. It is always advisable to consult with your local building control department or a qualified building professional to ensure compliance with the current regulations and to obtain the most accurate and up-to-date information regarding thermal efficiency calculations for extensions in England.  We work in partnership with Fenton Energy who are registered assessors.

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As part of the build detail we did specifiy a warm deck flat roof which will create little or no thermal bridging. This ensures there is no unnecessary heat-loss through joints or fixings. A warm roof is breathable, allowing moisture out. A breathable roof ensures there is no moisture build up which can lead to fungal or mould growth. A warm flat roof can be retrofitted without too many complications. This means that in some cases (not all) the roof can be fitted right over the existing roof. Warm roofs allows heat to be retained within the property. Warm roofs are simply insulated more efficiently than cold roofs because of the way they are formed. When retrofitted, warm roofs can be considerably cheaper to install than a cold roof. This means saving money that can be spent on improving other areas of the building.

 

We also specified a traditional cavity wall construction for an extension can offer several benefits: Cavity walls typically consist of an inner and outer leaf with a gap (cavity) between them. This design allows for the installation of insulation material within the cavity, providing better thermal insulation compared to solid walls. Improved insulation can help regulate the temperature inside the extension, reducing heat loss in winter and heat gain in summer, resulting in energy savings and increased comfort.

 

The cavity in traditional cavity wall construction acts as a barrier against moisture penetration. Rainwater that infiltrates the outer leaf of the wall is directed downward and drained out through weep holes, preventing moisture from reaching the inner leaf. This helps protect the interior of the extension from dampness and potential water damage. The air gap within the cavity also serves as an effective sound barrier. The two layers of brick or blockwork, combined with the cavity, can reduce the transmission of external noise into the extension, providing a quieter indoor environment.  The dual-leaf design of cavity walls enhances the structural stability of the extension. The inner and outer leaves work together to distribute the load, making the wall more resistant to movement and settlement. This helps ensure the long-term integrity of the extension's structure. Traditional cavity walls allow for flexibility in terms of construction materials and techniques. It is possible to choose different materials for the inner and outer leaves, allowing for customization based on factors such as aesthetics, cost, or availability. Additionally, the cavity can accommodate additional services such as electrical wiring or plumbing, making future modifications or upgrades more accessible.

 

Further Information

 

We also have a dedicated Building Regulations page that details further example of how we have helped clients with detailed building plans that have allowed clients and builders to finish projects safe in the knowledge that the technical detail has received approval from an approved Building Inspector.

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If you would like to find out more about how our Planning Consultancy and Architectural Design Services can work in perfect sync to achieve a successful outcome in the planning system please contact us and we will be only too happy to talk through any questions or development proposals you may have.

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