Detailed Technical Design & Building Regulations
KD Design provides detailed technical design and Building Regulations drawings for extensions, renovations and new homes across Oxfordshire.
Planning permission establishes what can be built. Detailed technical design works out how it will actually be built.
Often referred to as RIBA Stage 4 Technical Design, Detailed Design or Working Drawings, this is where an approved design is developed into the drawings, specifications and coordinated information needed for Building Regulations, contractor pricing and construction.
KD Design considers the structure, insulation, roofs, walls, floors, drainage, windows and doors, materials and the junctions between new and existing construction, resolving as much as possible before work begins on site.
Clear information
Better coordination
Fewer assumptions on site.
From Planning Permission to Construction
Planning drawings are prepared to visualise the design and secure planning permission. They do not normally contain all the information a builder needs to accurately price and construct the project.
Stage 4 technical design takes that same approved scheme and develops it into detailed construction information.
Same building. A completely different level of detail.
The RIBA Stage 4 detailed drawings coordinate how the building will actually be constructed, including the Foundations, structure, insulation, wall, floor and roof build ups, materials, openings, junctions and other details required for Building Regulations approval and construction.
A good technical design package is therefore much more than a set of Building Regulations drawings. It provides the information needed to turn an approved architectural design into something that can be accurately priced and built.
Already Have Planning Permission?
You do not need to have used KD Design for the planning stage.
We regularly take projects forward where planning permission has already been obtained by another architect, architectural designer or planning consultant.
Where the original architect wishes to remain involved, KD Design is also happy to work collaboratively. We can focus on the Stage 4 technical design, Building Regulations and construction information while the original architect retains oversight of the wider design direction.
KD Design can review the approved drawings and develop the project through RIBA Stage 4 technical design and Building Regulations, preparing the detailed construction drawings, specifications and coordinated information needed to get the project ready for pricing and construction.
Where required, we can also coordinate with structural engineers, energy assessors and other specialist consultants, bringing their information together within the architectural design.
The scheme was originally designed and planning permission secured by the previous architect. KD Design was then appointed to take the project forward through RIBA Stage 4 Detailed Design, Building Regulations and site support during construction.
What Stage 4 Technical Design Includes
KD Design develops the detailed technical information needed to move an approved design towards Building Regulations, contractor pricing and construction. A typical Stage 4 package for a dwelling will usually include the main architectural drawings and specification information needed to explain how the building is to be constructed.
This would normally include:
Detailed plans
Dimensions, wall construction, openings, levels and other key technical information.
Detailed sections
Floor, wall and roof construction, insulation, structure and important vertical relationships.
Detailed elevations
Materials, openings, levels, rainwater goods, vents and other external technical information.
Key construction details
Larger scale drawings where important junctions or interfaces need to be explained more clearly.
Specification notes
Technical notes covering materials, construction methods, performance requirements and relevant Building Regulations information.
Energy & Building Regulations
We coordinate the insulation, glazing, ventilation and energy performance requirements needed to demonstrate compliance with the Building Regulations.
This information is incorporated into the architectural drawings and specification so that the thermal design is coordinated with the construction.
Structural Coordination
We work closely with the structural engineer throughout the technical design stage, incorporating their calculations and details into the architectural drawings and resolving the relationship between the structure and the wider design.
Specialist Consultants
Some projects require additional specialist input. This will usually include structural engineers and energy assessors and might also include ground investigation specialists, drainage consultants or other specialists.
KD Design can help identify, appoint and coordinate the consultants needed for the project.
Building Regulations Submission
We prepare and submit the architectural drawings and supporting information required for a Full Plans Building Regulations application.
Where appointed as Building Regulations Principal Designer, KD Design also coordinates the design team and manages the design compliance process through the Building Regulations stage.
Structural Warranty
Where a structural warranty provider is appointed, KD Design can work with them during the technical design stage to provide any additional drawings and information they require. We can respond to technical queries and incorporate any reasonable warranty requirements into the Stage 4 package as the design develops.
CDM Principal Designer
Where appointed as CDM Principal Designer, KD Design coordinates health and safety during the pre construction phase and helps ensure that significant design risks are identified and communicated to the contractor and wider project team.
Additional Design Packages
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Drainage, Levels & Hard Landscaping
Detailed foul and surface water drainage layouts, external levels, falls, paving, steps and other hard landscaping around the building. Where required, this can also include soakaway locations, coordination with site levels and information needed for drainage approvals or Thames Water build over agreements.
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Windows & Doors
Detailed window and door schedules showing sizes, materials, opening types and key performance requirements. We can also prepare threshold, cill, lintel and reveal details where these need to be properly resolved before manufacture or construction.
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Kitchen & Bathroom Design
Detailed bathroom layouts and internal elevations showing sanitaryware, showers, niches, boxing and key dimensions. This helps coordinate the room before first fix and gives the contractor a clearer basis for setting out.
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Electrical & Heating Design
Additional coordination of heating, ventilation, lighting, sockets, controls and other services with the architectural design. This is particularly useful where layouts are complex or where the position of fittings needs to be agreed before construction starts.
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Timber Frame & Structural Detailing
Additional detailing and coordination for timber frame construction, exposed structure, steelwork interfaces and other more complex structural areas. This can help bring the architect’s and engineer’s information together into a clearer construction package.
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Specialist Construction Detailing
Larger scale drawings for areas that need more detail, such as roof junctions, thresholds, parapets, balconies, cladding or unusual construction. These details are prepared where the standard plans and sections are not enough to explain the design clearly.
The Detail Is in the Drawing
Good technical design is often about resolving the junctions between different parts of the building.
Roofs, walls, floors, glazing, structure and external levels all have to come together properly. Stage 4 is where these interfaces are worked through in detail before they become questions on site.
Select the highlighted areas to explore the construction details.
Better Information. Better Tender Prices.
A contractor can only price the information they are given.
A well developed Stage 4 package gives contractors a much clearer understanding of the work before they prepare their quotation. Materials, construction methods, dimensions and key junctions can be resolved and documented rather than left to assumption, helping to produce more complete and comparable tender prices with fewer provisional sums and unknowns.
Good technical design cannot remove every unexpected cost from a building project, but resolving more of the design before construction starts gives both the client and contractor a much stronger basis for pricing and construction.
You will deal directly with Keith throughout the process, from the initial review of the approved drawings through detailed design, Building Regulations and construction support where appointed.
The aim is simple: resolve it on the drawing before it becomes a question on site.
Some of our recently completed projects….
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New Dwelling, Cumnor Hill, Oxon
Contemporary replacement dwellings. KD design arranged Planning amendments to original planning consent and went on to provide Stage 4 detailed design and Site support to main contractor.
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Replacement dwelling, Cumnor, Oxon
Existing bungalow was demolished to make way for new spacious Family dwelling in the Oxford Green Belt. KD Design gained planning consent, provided Stage 4 detailed Design and Site support to main contractor.
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Single New Dwelling, Abingdon
KD Design gained planning consent and provided detailed Stage 4 drawings for Single 4-bed family home.
131m2 total floor area
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Modern Barn Conversion, Oxfordshire
Planning consent granted following Class Q consent to convert modern concrete framed Cow shed into spacious single family residence.
Frequently Asked Questions
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Yes. It is quite common for one architect or designer to prepare the planning application and another practice to take the project forward through technical design and construction. KD Design regularly takes over approved projects at this stage. You should also check your existing appointment and your rights to use the original design information.
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Yes. We can review the approved planning drawings and develop the project into the detailed technical information required for Building Regulations, contractor pricing and construction.
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Yes. I am happy to work alongside your existing architect where they wish to remain involved with the project. They can continue to oversee the overall design direction while KD Design focuses on the technical detailing, Building Regulations information and construction drawings needed to make the project clear, buildable and compliant.
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Planning drawings are primarily prepared to explain the design, appearance and scale of a proposal so that planning permission can be considered. Building Regulations and Stage 4 drawings develop the scheme in much greater technical detail, including construction, insulation, structure, materials and key junctions.
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They overlap, but a comprehensive Stage 4 technical design package can go further than the minimum information needed simply to obtain Building Regulations approval. It can also provide the coordinated drawings, specification and construction details needed for accurate contractor pricing and construction.
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Yes. The level of involvement can be tailored to suit your project and your needs.
For some projects, KD Design remains involved on a light touch basis as Building Regulations Principal Designer, helping with Building Regulations queries as construction progresses.
Where more support is required, I can also provide a more active role during the build, including regular site visits, reviewing construction details, responding to contractor queries and helping to resolve issues as they arise.
The service can be customised depending on how much support you would like during construction.
Already Have Planning Permission?
If planning permission is already in place and you now need detailed technical design, Building Regulations drawings or construction information, KD Design can take the project forward from the approved design through to contractor pricing and construction.
Whether the planning work was prepared by KD Design or by another architect, architectural designer or planning consultant, we can review the approved scheme and develop the technical information needed to get the project ready to build.