The Rowan
A one-bedroom starting point with an open living area and a separate private bedroom. Adapt the arrangement to the occupant and site.
Explore the RowanTRJ CONSTRUCTION LTD · BESPOKE SIP BUILDINGS
Granny Annexes in Theydon Bois
Create a more independent way of living, close to the people who matter. TRJ Construction Ltd designs and builds bespoke SIP granny annexes for homes in Theydon Bois, with the layout, access and services considered together.
Built around your brief. Quoted for your site.
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YOUR THEYDON BOIS PROJECT
A home designed from the entrance inward
A Theydon Bois annexe should make arrivals easy, with somewhere to set down shopping and a straightforward route to the kitchen. Consider future mobility at this stage. Door positions, bathroom space and the outside path are harder to change once the structure and drainage have been installed.
Bring a rough garden plan, photographs and a list of what the building needs to do. We can then discuss the position, orientation, access and service connections before narrowing down the layout. A design that works on paper must also work with the route into your garden.
CHOOSE YOUR STARTING POINT
A model to develop into your own home
These model layouts are starting points, not a fixed promise of what will fit every plot. Adapt the rooms, glazing and access to the site and occupant.
The Ash
Compare a two-bedroom layout when a second bedroom or a separate room for visitors is part of the brief.
Explore the AshThe Oak Accessible
Put circulation, easier access and the bathroom arrangement at the centre of the design discussion.
Explore accessible designREAL WORK · REAL LOCATIONS
Ideas from completed TRJ projects
Explore the photographs and details of these individual builds. The location and project credit stay with each example, so you can distinguish inspiration from a job completed in Theydon Bois.
Granny Annexe in Cheshunt
From the TRJ Construction project portfolio.
Project location: Cheshunt. See the case study for its own specification.
Waltham Cross Granny Annexe
From the TRJ Construction project portfolio.
Project location: Waltham Cross. See the case study for its own specification.
Granny Annexe in Epping Green
From the TRJ Construction project portfolio.
Project location: Epping Green. See the case study for its own specification.
FROM BRIEF TO BUILD
A clear scope before construction
For your Theydon Bois granny annexe, resolve the practical details early so the finished space supports the way you intend to use it.
Start with people and purpose
Discuss who will live here, privacy, visitors, storage and any mobility needs. Test everyday routes between the bedroom, bathroom and kitchen.
Understand the garden
Assess delivery access, levels, foundations, trees and boundaries. Map the route for power , water and drainage rather than leaving it to the end.
Agree the specification
Review the SIP structure, cladding, glazing, heating, ventilation and finishes. Confirm approvals, responsibilities, inclusions and the construction programme in writing.
Build and hand over
Coordinate the agreed works and relevant inspections. At handover, review the installation, operating information and documentation applicable to your project.
PLAN WITH CONFIDENCE
Annexe planning permission and building control
An annexe used for sleeping and day-to-day living needs a site-specific planning assessment. Do not assume the permitted-development rules for an incidental garden office cover a self-contained home. Check the proposed use and design with the local planning authority before building. Building regulations are a separate process: the structure, fire safety, insulation, ventilation, drainage and services must be considered with building control. Agree the approval route, inspections and completion documentation before work starts.
Check the council responsible for the property's postcode. Conservation designations, protected trees, previous permissions and site constraints can affect the proposal. We can discuss the construction information needed; the authority or appointed building control body determines the applicable approval process.
BUDGET & SPECIFICATION
Price the complete project
A useful budget covers more than the shell. Foundations, access, external works, glazing and the distance to services can change the overall cost. Kitchen and bathroom fittings, hot water, drainage and access requirements also need a clear allowance.
Request a written quotation for your Theydon Bois property, with VAT, inclusions, exclusions and approval or professional fees clearly identified. The programme should reflect site conditions and the agreed approval route.
Explore the annexe specification · Compare external cladding · Understand SIP construction
YOUR QUESTIONS
Granny Annexes in Theydon Bois: useful answers
Can TRJ build a granny annexe in Theydon Bois?
Yes, Theydon Bois is included in our service area. The first step is to assess your intended use, garden position, access and service routes. A quotation and programme follow the agreed scope and site assessment.
How should I start planning my Theydon Bois granny annexe?
A Theydon Bois annexe should make arrivals easy, with somewhere to set down shopping and a straightforward route to the kitchen. Consider future mobility at this stage. Door positions, bathroom space and the outside path are harder to change once the structure and drainage have been installed.
What affects the cost of a granny annexe in Theydon Bois?
Floor area is only part of the budget. Ground conditions, foundations, access, glazing, interior finishes and service connections can all change the scope. Ask for a written quotation that identifies inclusions, exclusions, VAT and any approval or professional fees.
Does a granny annexe need planning permission and building control approval?
An annexe used for sleeping and day-to-day living needs a site-specific planning assessment. Do not assume the permitted-development rules for an incidental garden office cover a self-contained home. Check the proposed use and design with the local planning authority before building. Building regulations are a separate process: the structure, fire safety, insulation, ventilation, drainage and services must be considered with building control. Agree the approval route, inspections and completion documentation before work starts.
Can the layout include a kitchen, shower room and accessible features?
Yes, these can form part of a bespoke design. We need to establish the available space, drainage and water routes, electrical requirements and approval position. Accessibility should be designed around the individual, including circulation, thresholds and bathroom use.
Are the photographs projects in this exact area?
Each photograph is labelled with its real project location. The images show completed work from the TRJ portfolio as design inspiration; they are not presented as projects in this area unless the caption says so. Work undertaken for Garden Spaces is credited alongside the relevant example.
Read before you build
Planning an annexeAnnexe design, costs and constructionDesigning for accessibilityBathrooms and shower rooms
Prepared by TRJ Construction Ltd. Meet the team behind the work. General project guidance; the assessment and approvals must relate to your particular site.
Other areas we cover
Also looking for a different type of space? Garden Rooms in Theydon Bois.
- IngatestoneGarden rooms · Granny annexes
- BrentwoodGarden rooms · Granny annexes
- ShenfieldGarden rooms · Granny annexes
- HuttonGarden rooms · Granny annexes
LET’S TALK ABOUT YOUR GARDEN
Your next space starts with a conversation.
Tell us about your Theydon Bois property, the intended use and the features that matter most.
